The U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency, collected water-quality samples and environmental data in Lake Koocanusa (also known as “Koocanusa Reservoir”), the Kootenai River, and the Tobacco River during water years 2022–23. The transboundary Lake Koocanusa is in southeastern British Columbia, Canada, and northwestern Montana, United States. It was formed by constructing Libby Dam on the Kootenai River 26 kilometers upstream from Libby, Montana. One of the lake sites and the Kootenai River site, in the Libby Dam tailwater (the outflow of the lake flow into the Kootenai River), were equipped with automated, high-frequency ServoSipper water samplers. At the lake site, these samplers were mounted to pontoon platforms during the summer, and a submersible ServoSipper sipper was deployed with ice buoys during the winter. Samples were automatically collected from multiple depths. At the Kootenai River site, these samplers were housed in the gage house. In water year 2022, discrete water-quality samples were collected every 4–6 weeks, year round, at all four lake sites in the Kootenai River between April and November. In water year 2023, discrete water-quality samples were collected at three lake sites and the Kootenai and Tobacco River sites every 4–6 weeks. The goal of this project was to collect multidepth, high-frequency vertical and temporal water-quality samples and data to understand the limnological and biological processes that control variations and trends in selenium concentrations and loads throughout Lake Koocanusa and in the Libby Dam tailwater at the southern end of the lake. This sampling and analysis plan documents the organization, sampling and data-collection scheme and design, pre- and post-collection processes, and quality-assurance and quality-control procedures of the Koocanusa/Kootenai water-quality monitoring program during water years 2022–23.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/ofr20261005","usgsCitation":"King, L.R., Caldwell Eldridge, S.L., Schaar, M.A., Schmidt, T.S., Chapin, T., and Bussell, A.M., 2026, Sampling and analysis plan for the water-quality monitoring program in Lake Koocanusa and upper Kootenai River, Montana, water years 2022–23: U.S. Geological Survey Open-File Report 2026–1005, 39 p., https://doi.org/10.3133/ofr20261005.","productDescription":"vi, 39 p.","numberOfPages":"50","onlineOnly":"Y","additionalOnlineFiles":"N","ipdsId":"IP-149144","costCenters":[{"id":685,"text":"Wyoming-Montana Water Science Center","active":false,"usgs":true},{"id":35995,"text":"Geology, Geophysics, and Geochemistry Science Center","active":true,"usgs":true}],"links":[{"id":502178,"rank":6,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_119339.htm","linkFileType":{"id":5,"text":"html"}},{"id":502024,"rank":4,"type":{"id":34,"text":"Image Folder"},"url":"https://pubs.usgs.gov/of/2026/1005/images/"},{"id":502022,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/of/2026/1005/ofr20261005.pdf","text":"Report","size":"3.2 MB","linkFileType":{"id":1,"text":"pdf"},"description":"OFR 2026-1005"},{"id":502023,"rank":3,"type":{"id":31,"text":"Publication XML"},"url":"https://pubs.usgs.gov/of/2026/1005/ofr20261005.XML"},{"id":502021,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/of/2026/1005/coverthb.jpg"},{"id":502025,"rank":5,"type":{"id":39,"text":"HTML Document"},"url":"https://pubs.usgs.gov/publication/ofr20261005/full"}],"country":"United States","state":"Montana","otherGeospatial":"Lake Koocanusa and Upper Kootenai River","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -114.9429682076028,\n 48.99647573554873\n ],\n [\n -116.0375564422092,\n 48.99647573554873\n ],\n [\n -116.0375564422092,\n 48.33063827945506\n ],\n [\n -114.9429682076028,\n 48.33063827945506\n ],\n [\n -114.9429682076028,\n 48.99647573554873\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","contact":"Director, Wyoming-Montana Water Science Center
U.S. Geological Survey
3162 Bozeman Avenue
Helena, MT 59601
The Delaware River basin (DRB) provides drinking water to 15 million people in the surrounding area. Water is frequently withdrawn from the freshwater reaches of streams, above head of tide, in the DRB for use as public drinking water. During extended periods of low flow, saltwater can move upstream, which can threaten drinking-water supplies in the basin. Due to spatial patterns in bathymetry, tidal influences within the DRB, and varying weather conditions, it can be hard to predict the movement and upstream extent of the freshwater-saltwater interface, often defined as the salt-front. Although there is a relationship that predicts this location in the main stem of the Delaware River, there lacks a relationship for its tributaries, such as the Maurice and Cohansey Rivers in southwestern New Jersey. In this study, a relationship was developed between daily specific conductance (SC) at gage locations along the tidal river reaches of the Maurice and Cohansey Rivers to the daily upstream location of the salt-front. The study augmented existing real-time tide gage data with the collection of water temperature and specific conductance data to develop the relationship. Additionally, longitudinal profiles upstream of the selected tide gages were conducted during a range of high tide conditions to define the location of the salt-front. Equations were then developed that related the daily SC measured at the tide gage to the upstream location of the salt-front. The equations were used to estimate the daily upstream location of the salt-front for the period of July 15, 2021, to July 15, 2024. This work can aid in understanding the propagation of saltwater upstream, which can affect local communities and crop farmers along these tidal reaches of the DRB.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20255090","programNote":"Next Generation Water Observing Systems","usgsCitation":"Closson, J.L., Suro, T.P., and Niemoczynski, L.M., 2026, Methods for estimating daily upstream location of the\nfreshwater-saltwater interface along the Maurice and Cohansey Rivers, New Jersey: U.S. Geological Survey\nScientific Investigations Report 2025–5090, 19 p., https://doi.org/10.3133/sir20255090.","productDescription":"Report: v, 19 p.; Data Release","numberOfPages":"19","onlineOnly":"Y","additionalOnlineFiles":"N","ipdsId":"IP-165703","costCenters":[{"id":470,"text":"New Jersey Water Science Center","active":true,"usgs":true}],"links":[{"id":501749,"rank":4,"type":{"id":31,"text":"Publication XML"},"url":"https://pubs.usgs.gov/sir/2025/5090/sir20255090.XML","linkFileType":{"id":8,"text":"xml"},"description":"SIR 2025-5090 XML"},{"id":501748,"rank":3,"type":{"id":39,"text":"HTML Document"},"url":"https://pubs.usgs.gov/publication/sir20255090/full","linkFileType":{"id":5,"text":"html"},"description":"SIR 2025-5090 HTML"},{"id":501747,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/sir/2025/5090/sir20255090.pdf","size":"4 MB","linkFileType":{"id":1,"text":"pdf"},"description":"SIR 2025-5090 PDF"},{"id":501744,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/sir/2025/5090/coverthb.jpg"},{"id":502173,"rank":7,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_119338.htm","linkFileType":{"id":5,"text":"html"}},{"id":501751,"rank":6,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/P13AFSIP","text":"USGS data release","linkHelpText":"Measurements of specific conductance at selected locations along the Maurice and Cohansey Rivers in New Jersey from 2021-24"},{"id":501750,"rank":5,"type":{"id":34,"text":"Image Folder"},"url":"https://pubs.usgs.gov/sir/2025/5090/images/"}],"country":"United States","state":"New Jersey","otherGeospatial":"Maurice and Cohansey Rivers","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -75.55956607478444,\n 39.649881649287096\n ],\n [\n -75.55956607478444,\n 39.12910651391917\n ],\n [\n -74.40943284041703,\n 39.12910651391917\n ],\n [\n -74.40943284041703,\n 39.649881649287096\n ],\n [\n -75.55956607478444,\n 39.649881649287096\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","contact":"Director, New Jersey Water Science Center
U.S. Geological Survey
3450 Princeton Pike, Suite 110
Lawrenceville, New Jersey 08648
The Delaware River basin serves as the drinking water supply for 15 million people. However, saltwater can move upstream during low- flow periods, threatening this water supply. The study established a relationship between daily specific conductance and the position of the salt- front. Data were collected from existing U.S. Geological Survey tide gages and multiparameter water- quality sondes installed in 2021 to record specific conductance and water temperature. For the Maurice River, the salt- front varied from around 10.8 to 23.2 river miles over the study period. For the Cohansey River, it ranged between 18.5 to 20.4 river miles. The position of the salt- front depended on freshwater discharge from rainfall and tidal patterns. Low freshwater flows led to the salt- front moving upstream.
","publicationDate":"2026-04-02","publicationStatus":"PW","contributors":{"authors":[{"text":"Closson, Jennifer L. 0009-0008-3835-0248","orcid":"https://orcid.org/0009-0008-3835-0248","contributorId":368903,"corporation":false,"usgs":true,"family":"Closson","given":"Jennifer","middleInitial":"L.","affiliations":[{"id":470,"text":"New Jersey Water Science Center","active":true,"usgs":true}],"preferred":true,"id":958071,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Suro, Thomas P. 0000-0002-9476-6829 tsuro@usgs.gov","orcid":"https://orcid.org/0000-0002-9476-6829","contributorId":2841,"corporation":false,"usgs":true,"family":"Suro","given":"Thomas","email":"tsuro@usgs.gov","middleInitial":"P.","affiliations":[{"id":502,"text":"Office of Surface Water","active":true,"usgs":true},{"id":470,"text":"New Jersey Water Science Center","active":true,"usgs":true}],"preferred":true,"id":958072,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Niemoczynski, Lukasz M. 0000-0003-2008-9148","orcid":"https://orcid.org/0000-0003-2008-9148","contributorId":222171,"corporation":false,"usgs":true,"family":"Niemoczynski","given":"Lukasz","middleInitial":"M.","affiliations":[{"id":470,"text":"New Jersey Water Science Center","active":true,"usgs":true}],"preferred":true,"id":958073,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70274302,"text":"sir20265122 - 2026 - Thickness and other characteristics of overbank sediment deposited during an extreme flood in May 1978 along the Powder River, Montana","interactions":[],"lastModifiedDate":"2026-04-03T17:29:50.756881","indexId":"sir20265122","displayToPublicDate":"2026-04-01T18:10:00","publicationYear":"2026","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":334,"text":"Scientific Investigations Report","code":"SIR","onlineIssn":"2328-0328","printIssn":"2328-031X","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"2026-5122","displayTitle":"Thickness and Other Characteristics of Overbank Sediment Deposited During an Extreme Flood in May 1978 Along the Powder River, Montana","title":"Thickness and other characteristics of overbank sediment deposited during an extreme flood in May 1978 along the Powder River, Montana","docAbstract":"An extreme flood on the Powder River in southeastern Montana in May 1978 inundated its valley and deposited sediment on the floodplains and terraces at multiple heights. The recurrence interval for this flood was less than 1 percent in the reach between Moorhead and Broadus, Montana. Peak discharges at the U.S. Geological Survey streamgages at Moorhead and Broadus were 779 and 711 cubic meters per second (m3/s), respectively, the difference reflecting the water and sediment stored on the valley surfaces. Bankfull discharge depended on the height of the bank at the start of the valley transect and varied from 243 to 713 m3/s. Sediment-thickness and particle-size data were collected and analyzed in the autumn of 1978 by U.S. Geological Survey scientists at about 900 sites along 20 valley transects between Moorhead and Broadus, Mont. These transects were approximately orthogonal to the floodflow across the floodplain from near the edge of the channel to the high-water mark. Estimated maximum flood depths along these transects ranged from 0.9 to 4.2 meters.
Contrary to theory and controlled laboratory experiments, the distribution of sediment thickness and particle sizes along valley transects did not decrease systematically with distance from the main channel but were affected by the distribution of vegetation. Additionally, some water and sediment—primarily muds and silts—were conveyed by subsidiary channels (often connected to the main channel downriver from the valley transect) during the early stages of the flood before water overtopped the banks at the start of the valley transect. The vegetation created natural sediment traps in the recirculation and wake zones in the lee of trees and shrubs. Sediment that accumulated in these traps formed dunes and thus an undulating surface with many local maximums and minimums in sediment thicknesses. Sediment in the traps are referred to as lee dunes, which recorded flow conditions and a predominance of coarsening-upward sequence of particle sizes (mud to silt to sands) starting at the preflood surface. These sequences were associated with the rising limb of the hydrograph, and later as the flood began to recede, the lee dunes recorded a fining-upward sequence associated with the falling limb of the hydrograph.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston VA","doi":"10.3133/sir20265122","usgsCitation":"Moody, J.A., and Meade, R.H., 2026, Thickness and other characteristics of overbank sediment deposited during an extreme flood in May 1978 along the Powder River, Montana: U.S. Geological Survey Scientific Investigations Report 2026–5122, 171 p., https://doi.org/10.3133/sir20265122.","productDescription":"Report: vii, 171 p.; 2 Data Releases","onlineOnly":"Y","ipdsId":"IP-138009","costCenters":[{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true}],"links":[{"id":502176,"rank":8,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_119336.htm","linkFileType":{"id":5,"text":"html"}},{"id":501974,"rank":7,"type":{"id":39,"text":"HTML Document"},"url":"https://pubs.usgs.gov/publication/sir20265122/full","text":"Report","linkFileType":{"id":5,"text":"html"},"description":"SIR 2026-5122"},{"id":501545,"rank":6,"type":{"id":31,"text":"Publication XML"},"url":"https://pubs.usgs.gov/sir/2026/5122/sir20265122.xml"},{"id":501544,"rank":5,"type":{"id":34,"text":"Image Folder"},"url":"https://pubs.usgs.gov/sir/2026/5122/images"},{"id":501516,"rank":4,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/P9FW7BV0","text":"USGS data release","linkHelpText":"Thickness and characteristics of overbank sediment deposited during an extreme flood in May 1978 along Powder River, Montana, USA"},{"id":501512,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/sir/2026/5122/coverthb.jpg"},{"id":501513,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/sir/2026/5122/sir20265122.pdf","text":"Report","size":"24.9 MB","linkFileType":{"id":1,"text":"pdf"},"description":"SIR 2026-5122"},{"id":501515,"rank":3,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/F7TQ5ZRN","text":"USGS data release","linkHelpText":"Channel Cross-section Data for Powder River between Moorhead and Broadus, Montana from 1975 to 2019 (ver. 3.0, August 2020)"}],"country":"United States","state":"Montana","otherGeospatial":"Powder River","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -105.293826541244,\n 45.40690393539472\n ],\n [\n -105.49140782452875,\n 45.45840328213558\n ],\n [\n -106.02769987915833,\n 45.01117945121612\n ],\n [\n -105.76802162112723,\n 45.00918393356142\n ],\n [\n -105.293826541244,\n 45.40690393539472\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","contact":"Water Mission Area
U.S. Geological Survey
12201 Sunrise Valley Drive
Reston, VA 20192
The U.S. Geological Survey, with funding from the Idaho Department of Water Resources, developed a groundwater budget for the Mountain Home area in southern Idaho for irrigation year 2023 (November 1, 2022–October 31, 2023). This study focused on the water balance across the Cinder Cone Butte Critical Groundwater Area (CGWA), Mountain Home Groundwater Management Area (GWMA), and the rest of the study area (RoSA), compiling data from various sources, including precipitation records, groundwater level measurements, metered groundwater pumpage data, surface water diversions and evapotranspiration (ET) estimates derived from remote sensing satellite imagery, and ground-based reference data. Key inflow components included recharge from applied surface water irrigation (which incorporates incidental recharge from irrigation practices and conveyance losses), estimated tributary streamflow, and estimated mountain block recharge. The key outflow components were groundwater pumpage for irrigation, municipal, industrial, and domestic uses, and ET. Recharge from applied irrigation and mountain block recharge were the largest inflows, and groundwater pumpage for irrigation was the largest outflow.
The CGWA had a positive groundwater budget residual of 2,170 acre-feet (acre-ft), which contrasts with observed long-term groundwater level declines and historical trends of storage depletion. This positive residual is likely associated with unquantified outflows, including lateral groundwater flow out of the subregion, or other complexities, such as overestimated tributary contributions relative to the actual recharge for the 2023 water budget. The GWMA exhibited a positive residual of 56,563 acre-ft, primarily owing to recharge from applied surface water irrigation and areal recharge during a wetter-than-average year, which allowed irrigation entities to deliver more water from in-basin and out-of-basin reservoirs. The RoSA showed a large positive residual of 124,933 acre-ft. The interpretation of these positive residuals must account for significant uncertainties, including estimations of areal recharge, tributary streamflow (particularly losses and diversions), ET, the volume of surface water loss to the Snake River, lateral groundwater flows between subregions and across study area boundaries, and the unquantified groundwater discharge to the Snake River. These uncertainties, in combination with the complex hydrogeologic controls on water movement and limitations of remotely sensed data, directly affect the accuracy of water availability assessments.
Future data collection efforts would help reduce these uncertainties and support water resource management decisions in the Mountain Home area. Key efforts could include installing additional streamflow gaging stations (particularly to quantify tributary losses and gains and surface water losses to the Snake River), improving groundwater pumpage metering, and validating remotely sensed ET data with ground-based measurements. Furthermore, to better quantify unrepresented or highly uncertain fluxes, focused investigations on groundwater discharge to the Snake River, lateral groundwater flows between subregions and across study area boundaries, and a more robust determination of the actual influence and volume of mountain block recharge would help refine future water availability assessments for the Mountain Home area.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20265118","collaboration":"Prepared in cooperation with the Idaho Department of Water Resources","usgsCitation":"Thomas, P.M., 2026, Groundwater budget for the Mountain Home area, southern Idaho, 2022–23: U.S. Geological Survey Scientific Investigations Report 2026–5118, 41 p., https://doi.org/10.3133/sir20265118.","productDescription":"Report: ix, 41 p.; Data Release","numberOfPages":"56","onlineOnly":"Y","additionalOnlineFiles":"N","ipdsId":"IP-140358","costCenters":[{"id":343,"text":"Idaho Water Science Center","active":true,"usgs":true}],"links":[{"id":500654,"rank":7,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_119277.htm","linkFileType":{"id":5,"text":"html"}},{"id":500532,"rank":5,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/P13ZG67D","text":"USGS data release","linkHelpText":"Supporting data for 2022–2023 groundwater budget for the Mountain Home area, southern Idaho"},{"id":500531,"rank":4,"type":{"id":34,"text":"Image Folder"},"url":"https://pubs.usgs.gov/sir/2026/5118/images/"},{"id":500530,"rank":3,"type":{"id":31,"text":"Publication XML"},"url":"https://pubs.usgs.gov/sir/2026/5118/sir20265118.XML"},{"id":500528,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/sir/2026/5118/coverthb.jpg"},{"id":500529,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/sir/2026/5118/sir20265118.pdf","text":"Report","size":"4.8 MB","linkFileType":{"id":1,"text":"pdf"},"description":"SIR 2026-5118"},{"id":500533,"rank":6,"type":{"id":39,"text":"HTML Document"},"url":"https://pubs.usgs.gov/publication/sir20265118/full"}],"country":"United States","state":"Idaho","otherGeospatial":"Mountain Home area","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -116.5,\n 43.5\n ],\n [\n -116.5,\n 42.833\n ],\n [\n -115.0833,\n 42.833\n ],\n [\n -115.0833,\n 43.5\n ],\n [\n -116.5,\n 43.5\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","contact":"Director, Idaho Water Science Center
U.S. Geological Survey
230 Collins Rd
Boise, Idaho 83702-4520
Acadia National Park has had increases in the frequency and magnitude of precipitation in recent years, leading to increased flood flows, stream erosion, and costly infrastructure damage. To improve infrastructure management in a changing climate, the U.S. Geological Survey, in cooperation with the National Park Service, has developed multiple datasets that can help natural resource managers identify stream reaches and stream crossings that have the highest potential for erosion and flood damage within Acadia National Park. To develop these datasets, we first created a lidar- derived hydrography based on a 1- meter digital elevation model and then estimated peak flows at stream crossings and along the stream network using regional regression equations for Maine. We assessed the erosion potential of stream reaches by computing channel morphologic and hydrologic metrics associated with erosive power, such as stream steepness, topographic openness, and percent storage in the contributing watershed. Stream crossing flood vulnerability was assessed by comparing estimated peak flows to stream crossing conveyance capacities. Our results indicate that stream reaches in the headwaters of the Acadia National Park highlands such as Sargent, Penobscot, and Cadillac Mountain, have the highest erosion potential and generally coincide with reaches that have had erosion and infrastructure damage in the past. Stream crossings with the highest flood vulnerability are distributed throughout Mount Desert Island and Acadia National Park, especially south of Jordan Pond, north of Sargent Mountain, and surrounding Eagle Lake. Over a quarter of the total stream crossings have insufficient information to compute flood vulnerability and are often on the parts of the stream with the highest potential for erosion. The datasets allow users to identify stream reaches with the highest erosion potential, stream crossings that are most vulnerable to flood damage, and to highlight areas where supplemental field assessments could most effectively be completed.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20265116","collaboration":"Prepared in cooperation with the National Park Service","usgsCitation":"Armstrong, I.P., McCallister, M.A., Hyslop, K.M., and Benthem, A.J., 2026, Erosion potential and flood vulnerability of streams and stream crossings at Acadia National Park, Maine: U.S. Geological Survey Scientific Investigations Report 2026–5116, 21 p., https://doi.org/10.3133/sir20265116.","productDescription":"Report: vii, 21 p.; Data Release","numberOfPages":"21","onlineOnly":"Y","additionalOnlineFiles":"N","ipdsId":"IP-178032","costCenters":[{"id":466,"text":"New England Water Science Center","active":true,"usgs":true}],"links":[{"id":500752,"rank":9,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/P13Y2RY2","text":"USGS data release","linkHelpText":"Data for an Erosion and Flood Vulnerability Assessment of Streams and Stream Crossings at Acadia National Park, Maine"},{"id":500656,"rank":8,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_119275.htm","linkFileType":{"id":5,"text":"html"}},{"id":500517,"rank":7,"type":{"id":22,"text":"Related Work"},"url":"https://geonarrative.usgs.gov/acadiaerosionfloodvulnerability/","text":"Interactive dashboard","linkHelpText":"- Erosion Potential and Flood Vulnerability of Streams and Stream Crossings at Acadia National Park"},{"id":499819,"rank":3,"type":{"id":39,"text":"HTML Document"},"url":"https://pubs.usgs.gov/publication/sir20265116/full","linkFileType":{"id":5,"text":"html"},"description":"SIR 2026-5116 HTML"},{"id":499818,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/sir/2026/5116/sir20265116.pdf","size":"7.83 MB","linkFileType":{"id":1,"text":"pdf"},"description":"SIR 2026-5116 PDF"},{"id":499817,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/sir/2026/5116/coverthb.jpg"},{"id":499820,"rank":4,"type":{"id":31,"text":"Publication XML"},"url":"https://pubs.usgs.gov/sir/2026/5116/sir20265116.xml","linkFileType":{"id":8,"text":"xml"},"description":"SIR 2026-5116 XML"},{"id":499821,"rank":5,"type":{"id":34,"text":"Image Folder"},"url":"https://pubs.usgs.gov/sir/2026/5116/images/"},{"id":499822,"rank":6,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/P1EHZNHN","text":"USGS data release","linkHelpText":"Data for an erosion potential and flood vulnerability assessment of streams and stream crossings at Acadia National Park, Maine"}],"country":"United States","state":"Maine","otherGeospatial":"Acadia National Park","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -68.45003175798666,\n 44.44178922865794\n ],\n [\n -68.45003175798666,\n 44.21621316604151\n ],\n [\n -68.13514216440173,\n 44.21621316604151\n ],\n [\n -68.13514216440173,\n 44.44178922865794\n ],\n [\n -68.45003175798666,\n 44.44178922865794\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","contact":"Director, New England Water Science Center
U.S. Geological Survey
10 Bearfoot Rd.
Northborough, Massachusetts 01532
The U.S. Geological Survey, in cooperation with the National Park Service, has developed multiple datasets that can help natural resource managers identify stream reaches with the highest potential for erosion and stream crossings most vulnerable to flood damage within Acadia National Park. These datasets allow users to identify areas where supplemental field assessments could be most effectively completed.
","publicationDate":"2026-02-26","publicationStatus":"PW","contributors":{"authors":[{"text":"Armstrong, Ian P. 0000-0002-8239-8029","orcid":"https://orcid.org/0000-0002-8239-8029","contributorId":344363,"corporation":false,"usgs":true,"family":"Armstrong","given":"Ian","email":"","middleInitial":"P.","affiliations":[{"id":466,"text":"New England Water Science Center","active":true,"usgs":true}],"preferred":true,"id":955710,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"McCallister, Meghan A. 0000-0001-8814-7725","orcid":"https://orcid.org/0000-0001-8814-7725","contributorId":358213,"corporation":false,"usgs":true,"family":"McCallister","given":"Meghan","middleInitial":"A.","affiliations":[{"id":466,"text":"New England Water Science Center","active":true,"usgs":true}],"preferred":true,"id":955711,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hyslop, Kristina M. 0009-0001-2525-5574","orcid":"https://orcid.org/0009-0001-2525-5574","contributorId":334465,"corporation":false,"usgs":true,"family":"Hyslop","given":"Kristina","middleInitial":"M.","affiliations":[{"id":466,"text":"New England Water Science Center","active":true,"usgs":true}],"preferred":true,"id":955712,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Benthem, Adam J. 0000-0003-2372-0281","orcid":"https://orcid.org/0000-0003-2372-0281","contributorId":220000,"corporation":false,"usgs":true,"family":"Benthem","given":"Adam","middleInitial":"J.","affiliations":[{"id":466,"text":"New England Water Science Center","active":true,"usgs":true}],"preferred":true,"id":955713,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70273923,"text":"sir20265120 - 2026 - Methods for estimating selected streamflow statistics at ungaged sites in Wyoming based on data through water year 2021","interactions":[],"lastModifiedDate":"2026-02-27T21:40:16.939028","indexId":"sir20265120","displayToPublicDate":"2026-02-26T07:11:17","publicationYear":"2026","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":334,"text":"Scientific Investigations Report","code":"SIR","onlineIssn":"2328-0328","printIssn":"2328-031X","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"2026-5120","displayTitle":"Methods for Estimating Selected Streamflow Statistics at Ungaged Sites in Wyoming Based on Data Through Water Year 2021","title":"Methods for estimating selected streamflow statistics at ungaged sites in Wyoming based on data through water year 2021","docAbstract":"The U.S. Geological Survey, in cooperation with the Wyoming Water Development Office, developed regional regression equations based on basin characteristics and streamflow statistics for streamgages through water year 2021 (October 1, 2020, to September 30, 2021). The regression equations allow estimates of mean annual maximum, mean annual, mean seasonal, and mean monthly streamflows; frequency statistics for the 7- day mean low flows with 2- year and 10- year recurrence intervals, 14- and 30- day mean low flows with 5- year recurrence intervals, and 60- and 1- day mean high flow with 2- year and 5- year recurrence intervals, respectively; and the 0.1- , 0.2- , 0.5- , 1- , 2- , 4- , 5- , 10- , 20- , 25- , 30- , 50- , 60- , 70- , 75- , 80- , 90- , 95- , 98- , and 99- percent durations for annual streamflows and 0.1- , 0.5- , 10- , 15- , 20- , 25- , 30- , 40- , 50- , 60- , 70- , 75- , 80- , 85- , 90- , 95- , and 99- percent durations for monthly streamflows for most months for ungaged locations in Wyoming that are largely unaltered by diversions or upstream reservoirs.
Regression equations were developed for 243 streamflow statistics. Best- subset selection was used to assess explanatory variables for respective streamflow statistics. Exploratory data analyses determined that, of the 81 basin characteristics evaluated as potential explanatory variables, characteristics such as drainage area and precipitation often produced models with the highest adjusted coefficient of determination and lowest mean squared error, as determined in the best- subset selection. To address heteroskedasticity of model residuals, model variables were regionalized using fixed- effects models; the percentages of the streamgage basins in selected ecoregions were defined as interaction terms, which represent the model slope for specific ecoregions. Most models were determined to be statistically significant for probability values less than or equal to 0.1 for one or more regional explanatory variables. The final regional regression equations defined in this report are available for use in the U.S. Geological Survey’s StreamStats web application at https://streamstats.usgs.gov/ss/.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20265120","collaboration":"Prepared in cooperation with the Wyoming Water Development Office","usgsCitation":"Taylor, N.J., and Sando, R., 2026, Methods for estimating selected streamflow statistics at ungaged sites in Wyoming based on data through water year 2021: U.S. Geological Survey Scientific Investigations Report 2026–5120, 38 p., https://doi.org/10.3133/sir20265120.","productDescription":"Report: vii, 38 p.; 1 Linked Appendix Table; Data Release; Dataset","numberOfPages":"50","onlineOnly":"Y","additionalOnlineFiles":"Y","ipdsId":"IP-179497","costCenters":[{"id":685,"text":"Wyoming-Montana Water Science Center","active":false,"usgs":true}],"links":[{"id":500657,"rank":9,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_119274.htm","linkFileType":{"id":5,"text":"html"}},{"id":500117,"rank":8,"type":{"id":39,"text":"HTML Document"},"url":"https://pubs.usgs.gov/publication/sir20265120/full"},{"id":500115,"rank":7,"type":{"id":28,"text":"Dataset"},"url":"https://doi.org/10.5066/F7P55KJN","text":"USGS National Water Information System database","linkHelpText":"- USGS water data for the Nation"},{"id":500111,"rank":3,"type":{"id":31,"text":"Publication XML"},"url":"https://pubs.usgs.gov/sir/2026/5120/sir20265120.XML"},{"id":500114,"rank":6,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/P14WLVAH","text":"USGS data release","linkHelpText":"Regression equations for selected streamflow statistics based on data through water year 2021 in and near Wyoming"},{"id":500113,"rank":5,"type":{"id":27,"text":"Table"},"url":"https://pubs.usgs.gov/sir/2026/5120/downloads/","text":"Table 1.1","size":"60 KB","linkFileType":{"id":3,"text":"xlsx"}},{"id":500112,"rank":4,"type":{"id":34,"text":"Image Folder"},"url":"https://pubs.usgs.gov/sir/2026/5120/images/"},{"id":500110,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/sir/2026/5120/sir20265120.pdf","text":"Report","size":"7.2 MB","linkFileType":{"id":1,"text":"pdf"},"description":"SIR 2026-5120"},{"id":500109,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/sir/2026/5120/coverthb.jpg"}],"country":"United States","state":"Colorado, Idaho, Montana, North Dakota, South Dakota, Utah, Wyoming","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -113.82002110650585,\n 46.421867179561445\n ],\n [\n -113.82002110650585,\n 39.89961451938157\n ],\n [\n -103.32595673094282,\n 39.89961451938157\n ],\n [\n -103.32595673094282,\n 46.421867179561445\n ],\n [\n -113.82002110650585,\n 46.421867179561445\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","contact":"Director, Wyoming-Montana Water Science Center
U.S. Geological Survey
3162 Bozeman Avenue
Helena, MT 59601
Chlorinated solvents, including trichloroethene (TCE) and other chlorinated volatile organic compounds (cVOCs), are widespread contaminants that can be treated by bioremediation approaches that enhance anaerobic reductive dechlorination. Reductive dechlorination can be enhanced either through the addition of an electron donor (biostimulation) or the addition of a known dechlorinating culture (bioaugmentation) along with an electron donor. Although bioremediation has been applied at many TCE- contaminated groundwater sites, application in source zones at sites where residual dense nonaqueous phase liquid (DNAPL) is present is more limited. In this study, laboratory and field treatability tests were completed to evaluate the potential application of anaerobic bioremediation for a shallow groundwater plume containing TCE in a perched alluvial aquifer at Site K, former Twin Cities Army Ammunition Plant, Arden Hills, Minnesota, which was on the National Priorities List as the New Brighton/Arden Hills Superfund site until 2019. In addition to the presence of residual DNAPL at the site, temporal variability in groundwater flow directions and input of oxygenated recharge were possible complicating factors for the application of enhanced anaerobic biodegradation in the shallow plume. The Site K plume extends beneath the footprint of Building 103, which was demolished in 2006, and soil excavations to a maximum depth of 6 feet (ft) below ground surface in 2014 were known to leave some deeper contaminated soil in place in the TCE source area. Groundwater treatment at the site, formalized as part of the 1997 Record of Decision, has been in operation since 1986 and consists of an extraction trench at the downgradient edge of the plume to collect groundwater, which is then pumped to an on- site air stripper. Groundwater concentrations in the plume have been relatively stable since treatment began, indicating a continued source of TCE in the aquifer. The desire for a destructive remedy that would enhance the removal of cVOCs in the aquifer at Site K and shorten the remediation timeframe led the U.S. Army to request that the U.S. Geological Survey conduct a groundwater treatability study to assess bioremediation. This report describes the U.S. Geological Survey bioremediation treatability study conducted during 2020–22, including pre- design site characterization to assist in formulating the bioremediation approach, laboratory experiments to support the design of the field pilot test, and implementation and 1-year performance monitoring results for the pilot test.
Pre- design site characterization included the collection of soil cores for cVOC analysis and lithologic descriptions and the re- installment of three wells to obtain hydrologic measurements and initial groundwater chemistry. Relatively flat head gradients were measured at the site, and substantial decreases in water- level elevations occurred from spring to summer (May–July 2021). Continuous water- level monitoring indicated a rapid response to precipitation. Groundwater flow velocities were consistently less than 0.5 foot per day, and the pilot bioremediation test was therefore designed with short lateral distances (about 5 ft) between injection and individual monitoring points. Soil analyses confirmed that high volatile organic compound contamination was left in place in the source area. The highest concentrations were near or in clay at the base of the perched aquifer. Concentrations of cVOCs measured in the replaced wells were consistent with historical data and had a maximum TCE concentration of 57,700 micrograms per liter (μg/L), indicative of nearby residual DNAPL based on the general rule of observed concentrations exceeding 1 percent of solubility. The primary TCE daughter product detected was 1,2- cis- dichloroethene (cisDCE), which indicated limited reductive dechlorination in the plume. Groundwater in both the source and downgradient areas was relatively reducing during the pre- design characterization, particularly in the source area where methane concentrations greater than 400 μg/L were measured.
Initial laboratory tests conducted using native aquifer microorganisms from the three replacement wells showed that anaerobic TCE biodegradation rates were low when biostimulated with the addition of sodium lactate as an electron donor, also known as a carbon donor, and resulted in the production of only cisDCE. Addition of a known dechlorinating culture, WBC- 2, however, resulted in rapid biodegradation and production of ethene, verifying complete reductive dechlorination of TCE. Microcosms constructed with aquifer soil collected from the site were used to evaluate other electron donors besides lactate to support reductive dechlorination by WBC- 2, including corn syrup as an alternative fast- release compound and whey, soy- based vegetable oil, and 3- D Microemulsion (Regenesis, San Clemente, California) as slow-release compounds. First- order rate constants for total organic chlorine removal in these WBC- 2 amended microcosms were greatest with either lactate or vegetable oil as the donor, ranging between 0.061 and 0.047 per day or corresponding half- lives of 11–15 days. Testing of commercial products in other WBC- 2- bioaugmented microcosms led to selection for the field pilot test of an emulsified vegetable oil product that also contained some sodium lactate as a fast- release donor. Delaying the addition of WBC- 2 relative to the donor in the microcosms resulted in the most rapid overall biodegradation rates.
The selected design for the pilot test utilized three separate test plots, each about 30-ft wide and 60-ft long: plots GS1 and GS2 in the source area of the plume and plot GS3 in the downgradient area of the plume near the excavation trench. Each test plot had one injection well, one monitoring well upgradient from the injection point, and 12 surrounding monitoring wells in a grid to capture variable groundwater flow directions. Donor injections, which included a bromide tracer, were completed in October 2021, immediately following baseline sampling, and the WBC- 2 culture was injected about 40 days later, between November 30 and December 2, 2021. Performance monitoring conducted until December 2022 included hydrologic measurements and analyses of cVOCs, redox- sensitive constituents, dissolved organic carbon, bromide, volatile fatty acids, compound- specific carbon isotopes, and microbial communities.
The biogeochemical data collected during the pilot tests in the three treatment plots showed that enhanced, complete reductive dechlorination of cVOCs in the groundwater was achieved in the GS1 and GS3 plots. In contrast, evidence of distribution of the injected amendments and subsequent biodegradation was limited in GS2, which was in an area of more heterogeneous soil lithology and low water table elevations. The molar composition of volatile organic compounds in the GS1 and GS3 plots was dominated by ethene in wells that were reached by the injected amendments by the end of the monitoring period. In the GS1 and GS3 plots, similar patterns were observed of cVOC concentrations decreasing to near detection levels, or below, at some wells sampled in July and October 2022, whereas ethene became dominant and indicated sustained complete reductive dechlorination. Baseline cVOC concentrations were more than a factor of 10 higher in the groundwater in the GS1 plot than in GS3, but no apparent inhibition of complete dechlorination occurred. As expected from the initial pre- design site data and the laboratory experiments, enhanced dissolution of residual DNAPL coupled to biodegradation was evident in the GS1 plot, where a marked increase in dichloroethene (DCE) above the initial baseline and upgradient TCE and DCE concentrations occurred. DCE concentrations subsequently declined where DNAPL dissolution was evident, concurrent with production of vinyl chloride and then predominantly ethene. Thus, overall biodegradation rates outpaced the DNAPL dissolution and desorption and DCE production in the source area. This success in complete degradation to predominantly ethene was achieved even in areas where the DCE concentrations reached a maximum of about 30,000 μg/L. Compound specific isotope analysis of carbon in TCE, cisDCE, trans- 1,2- dichloroethene, and vinyl chloride was conducted to provide another line of evidence of the occurrence and extent of anaerobic biodegradation. Along a flow path in each plot that was affected by the injected amendments, carbon isotopes in the TCE and daughter cVOCs in the groundwater became isotopically heavier, indicating biodegradation.
Enhanced biodegradation rates calculated from the field tests in GS1 and GS3 showed half- lives of 36.9–75.3 days for DCE degradation and 9.48–38.5 days for ethene production. Notably, these ethene production rates calculated from the field tests are consistent with the results of WBC- 2- bioaugmented microcosms amended with either lactate or vegetable oil, which had half- lives for total organic chlorine removal that ranged from 11 to 15 days. These rates indicated rapid enhanced biodegradation, which is promising for application of a full- scale bioremediation remedy. Ultimately, however, the mass of residual or sorbed TCE in the aquifer that remains accessible for dissolution and biodegradation would likely control the time required for a full- scale bioremediation effort to achieve performance goals for TCE and cisDCE specified in the Record of Decision for Site K.
The field pilot tests showed that the relatively low hydraulic head gradients and temporal changes in groundwater flow directions in the shallow aquifer would add complexity to a full- scale bioremediation effort. The radius of influence (ROI) at GS1 and GS3 (16.3 ft and 12.7 ft, respectively) were close to the design ROI of 15 ft. The estimated ROI at GS2 was about four times the design ROI, but may be less reliable at this location owing to groundwater flow direction. In addition, the low temperatures following WBC- 2 injection in late November to early December 2021, in combination with the low hydraulic head gradients, were probably major factors in the delay observed before the onset of enhanced biodegradation following injection of the culture. Additional test injections could be beneficial to optimize the timing of donor and culture injections with the variable temperatures and hydraulic head in the shallow aquifer.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20255113","collaboration":"Prepared in cooperation with U.S. Army Environmental Command","usgsCitation":"Lorah, M.M., Majcher, E.H., Mumford, A.C., Foss, E.P., Needham, T.P., Psoras, A.W., Livdahl, C.T., Trost, J.J., Berg, A.M., Polite, B.F., Akob, D.M., and Cozzarelli, I.M., 2026, Treatability study to evaluate bioremediation of trichloroethene at Site K, former Twin Cities Army Ammunition Plant, Arden Hills, Minnesota, 2020–22: U.S. Geological Survey Scientific Investigations Report 2025–5113, 88 p., https://doi.org/10.3133/sir20255113.","productDescription":"Report: xii, 88 p.; Data Release","numberOfPages":"88","onlineOnly":"Y","additionalOnlineFiles":"N","ipdsId":"IP-175852","costCenters":[{"id":41514,"text":"Maryland-Delaware-District of Columbia Water Science Center","active":true,"usgs":true}],"links":[{"id":500361,"rank":7,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_119213.htm","linkFileType":{"id":5,"text":"html"}},{"id":500106,"rank":6,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/P13QTBR7","text":"USGS data release","linkHelpText":"Former Twin Cities Army Ammunition Site K treatability test data including various field measurements, laboratory tests and degradation constituents in the bioremediation of trichloroethylene and dichloroethylene, Arden Hills, Minnesota 2020–2022"},{"id":500104,"rank":4,"type":{"id":31,"text":"Publication XML"},"url":"https://pubs.usgs.gov/sir/2025/5113/sir20255113.XML","linkFileType":{"id":8,"text":"xml"},"description":"SIR 2025-5113 XML"},{"id":500103,"rank":3,"type":{"id":39,"text":"HTML Document"},"url":"https://pubs.usgs.gov/publication/sir20255113/full","linkFileType":{"id":5,"text":"html"},"description":"SIR 2025-5113 HTML"},{"id":500102,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/sir/2025/5113/sir20255113.pdf","size":"6.92 MB","linkFileType":{"id":1,"text":"pdf"},"description":"SIR 2025-5113 PDF"},{"id":500101,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/sir/2025/5113/coverthb.jpg"},{"id":500105,"rank":5,"type":{"id":34,"text":"Image Folder"},"url":"https://pubs.usgs.gov/sir/2025/5113/images/"}],"country":"United States","state":"Minnesota","county":"Ramsey County","city":"Arden Hills","otherGeospatial":"Site K, former Twin Cities Army Ammunition Plant","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -93.17794646411902,\n 45.1090420800339\n ],\n [\n -93.17794646411902,\n 45.08000250215488\n ],\n [\n -93.14480906199879,\n 45.08000250215488\n ],\n [\n -93.14480906199879,\n 45.1090420800339\n ],\n [\n -93.17794646411902,\n 45.1090420800339\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","contact":"Director, Maryland-Delaware-D.C. Water Science Center
U.S. Geological Survey
5522 Research Park Drive
Catonsville, MD 21228
The Puyallup River drains a 990 square mile watershed in western Washington, with headwaters on the glacier-covered flanks of Mount Rainier. Major tributaries include the White, Carbon, and Mowich Rivers. In the levee-confined reaches of the lower watershed, loss of flood conveyance due to sand and gravel deposition has been a chronic issue. Over much of the 20th century, flood conveyance was maintained through sediment removal, but this practice ended in the late 1990s. Flood hazard management activities since the 1990s have primarily involved levee removal or setback projects. Assessments of 1984-2009 repeat cross sections suggested that sediment deposition rates were particularly high in reaches with recent levee setbacks. However, there have been no assessments of recent deposition rates since the 2009 surveys. There are also concerns that intensifying flood hydrology or increased sediment delivery from Mount Rainier may exacerbate deposition. However, assessment of those risks has been hindered by limited understanding of watershed-scale sediment delivery and routing, particularly for coarse sand and gravel.
The U.S. Geological Survey, in cooperation with Pierce County, initiated this study to improve understanding of sediment deposition in the lower Puyallup River watershed. This work is primarily based on differencing of multiple aerial lidar datasets collected during 2002–2022, supplemented by early 1990 photogrammetric elevation datasets, geomorphic assessments of streamgage data, historical topographic surveys from 1907, and previously collected sediment transport measurements. Analyses cover the Puyallup, Carbon, and Mowich Rivers, but do not include the White River.
During 2004–2020, repeat aerial lidar indicates that 1.3 ± 0.3 million yd3 of sediment accumulated in the lower 20 valley miles (VMs) of the Puyallup River, averaging 80,000 ± 20,000 cubic yards per year (yd3/yr). Deposition was observed during both 2004–11 and 2011–20 lidar differencing intervals. This continued a long-term depositional trend that extends back to at least 1977. From 2004 to 2011, deposition rates along the Soldiers Home levee setback reach, the only setback project downstream of VM 20 completed prior to 2011, were approximately four times higher than in adjacent unmodified reaches. From 2011 to 2020, two additional setback projects were completed; volumetric deposition rates over all three setback reaches were similar to adjacent unmodified reaches, suggesting elevated setback deposition in the 2004–11 interval may have been influenced by an extreme flood in November 2006. These levee setback projects increased the local cross-sectional area of the floodway, used as a rough proxy for relative flood conveyance, by 50 to 200 percent above 2004 conditions. If deposition continued at recent rates, cross-sectional area over the levee setback reaches would be reduced back to 2004 values by 2050-90.
Deposition also occurred over the lower six VMs of the Carbon River during 2004–20, though volumes (0.15 ± 0.09 million yd3) were an order of magnitude lower than along the Puyallup River. Relatively lower deposition rates in the Carbon River are most likely the combined result of modestly lower incoming sediment loads, modestly steeper channel slope, and the additional sediment transport capacity provided by two large non-glacial tributaries that enter the Carbon River near VM 5.
Upstream of the depositional reaches described above, 2002–22 sediment storage trends along the Puyallup, Carbon, and Mowich Rivers were predominately negative (net erosion) up to the Mount Rainier National Park boundary. Net erosion was the result of bank and bluff erosion exceeding deposition across wetted channel and bare gravel areas, as opposed to uniform vertical downcutting. Net erosion along these river valleys delivered 3.4 ± 0.6 million yd3 to the river system, equivalent to 190,000 ± 35,000 yd3/yr. Most of that volume was supplied by erosion of relatively low (4–10 ft) surfaces along the Puyallup and Mowich Rivers and tall (300 ft) glacial bluffs along the lower Carbon River. Substantial aggradation from 1984 to 2009 reported by Czuba and others (2010) along reaches of the Puyallup River (VM 19–22) where levee confinement has recently been removed was most likely an artifact of methodologic bias.
The Puyallup, Mowich, and Carbon Rivers drain five distinct glaciated watersheds on the flanks of Mount Rainier, four of which were assessed in this study. All four watersheds were impacted by an extreme November 2006 rainstorm. Between 2002 and 2008, debris flows occurred in all four headwater areas, collectively eroding at least 2.1 million yd3 of sediment. These debris flows formed distinct deposits one to two miles downstream of source areas, depositing 30-50 percent of the material eroded upstream. From 2008 to 2022, no headwater debris flows were observed and overall rates of geomorphic change in the headwaters were low. Rivers eroded into debris flow deposits emplaced over the 2002–08 interval, but re-deposited equivalent volumes of material within a half mile downstream.
Stage-discharge relations at five streamgages on upland rivers draining Mount Rainier show either net channel incision or dynamic variability with no long-term trend over the past 60–100 years. Observations of pervasive river valley erosion and stable or incising trends at long-term streamgages in the upper watershed do not support prior claims of widespread and accelerating aggradation of upland rivers draining Mount Rainier.
Erosion and deposition volumes estimated in this report were combined with sediment transport estimates from limited suspended sediment and bedload measurements, estimates of sub-glacial erosion rates, and sediment delivery from non-glacial tributaries to construct watershed-scale sediment budgets for the Puyallup River watershed. During 2004–20, the estimated sediment load entering the depositional lowlands was well balanced by estimated inputs from, in order of relative magnitude, subglacial erosion (33–60 percent of total sediment load), erosion along the major river valleys (25–45 percent), erosion in recently deglaciated headwater areas (7–17 percent) and non-glacial tributaries (3–9 percent). These results are specific to the study period and represent total sediment loads, most of which is fine material carried in suspension. The relative sourcing of sand and gravel may be different than implied by this sediment budget.
Downstream of VM 12, comparison of 1907 and 2009 channel surveys show net lowering of the channel thalweg of 4–12 ft. A long-term gage near VM 22 shows lowering of 4–5 ft through the 1960s. Lowering at both locations was inferred to be a channel response to the substantial straightening, and so steepening, of the river during major phases of levee construction through the early and mid-20th century.
Application of a simple empirical bedload-discharge power-law relation to an ensemble of model-estimated daily mean discharge records in the lower Puyallup River between 1977 and 2100 projects that annual bedload transport capacity in the lower Puyallup River will increase by 20–60 percent by the middle of the 21st century. Actual changes in bedload transport and deposition rates will depend on concurrent changes in sediment supply and local hydraulics governing deposition.
This report presents several key conclusions. First, the persistence and spatial patterns of sand and gravel deposition along the lower Puyallup River support prior claims that deposition is fundamentally caused by decreases in channel slope moving downstream. Given this underlying cause and the abundance of sand and gravel available to be transported downstream, deposition is likely to continue for the foreseeable future. Second, despite continued sediment deposition, recent levee setback projects in the lower Puyallup River will likely provide several decades of flood conveyance benefits relative to a no-action alternative. Third, while the rivers linking Mount Rainier to the Puget Sound lowlands have often been discussed as conduits that either pass or accumulate sediment from Mount Rainier, observations from 2002–22 show these river valleys acting as substantial sediment sources, delivering three times more sediment than recently deglaciated headwater areas on Mount Rainier. While the persistence and underlying cause of recent river valley erosion remain unknown, sediment storage dynamics along these river valleys are likely to be a major control on sand and gravel delivery to the lower watershed.
Bathymetric and velocimetric data were collected by the U.S. Geological Survey, in cooperation with the Missouri Department of Transportation, near 8 bridge crossings of the Missouri River near Kansas City, Missouri, on August 8–9, 2023. A multibeam echosounder mapping system was used to obtain channel- bed elevations for river reaches that extended about 1,550 to 1,640 feet longitudinally and generally extended laterally across the active channel from bank to bank during low floodflow to nonflood conditions. These surveys provided the channel geometry and hydraulic conditions of the river at the time of the surveys and provided characteristics of scour holes, which may be useful in developing or verifying predictive guidelines or equations for computing potential scour depth. The data collected from the surveys may also be useful to the Missouri Department of Transportation as a record of low floodflow conditions in regards to the stability and integrity of the bridges with respect to bridge scour. Bathymetric data were collected around every in- channel pier. Scour holes were at most piers where bathymetry could be obtained, except for those piers on banks or surrounded by riprap. All the bridge sites in this study were surveyed and documented in previous studies.
The average difference between the bathymetric surfaces ranged from 0.07 to 4.16 feet higher in 2023 than 2019, which indicates overall deposition between the survey dates, as might be expected based purely on streamflow at the time of the survey. However, the average difference between the bathymetric surfaces ranged from 1.44 feet higher to 1.88 feet lower in 2023 than 2015, which indicates a dynamic equilibrium of scour and deposition overall between those surveys, despite the lower flow conditions in 2023. Similarly, the average difference between the bathymetric surfaces ranged from 3.18 feet higher to 5.19 feet lower in 2023 than 2011, which indicates a relative equilibrium between scour and deposition overall, albeit the trend was toward scour as might be expected because of the substantial flood event in 2011.
Riprap blankets and alignment to flow had a substantial effect on the size of the scour hole for a given pier. Piers that were partially or fully surrounded by riprap blankets had scour holes that were substantially smaller (to nonexistent) compared to piers with no rock or riprap and effectively mitigated the scour holes historically observed at these piers. Several of the structures had piers that were skewed to primary approach flow. At most of the structures, the scour hole was deeper and longer on the side of the pier with impinging flow than the leeward side, with some amount of deposition on the leeward side, as typically observed at piers skewed to approach flow.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20265124","collaboration":"Prepared in cooperation with Missouri Department of Transportation","usgsCitation":"Huizinga, R.J., and Rivers, B.C., 2026, Bathymetric and velocimetric surveys at highway bridges crossing the Missouri River near Kansas City, Missouri, August 8–9, 2023: U.S. Geological Survey Scientific Investigations Report 2026–5124, 105 p., https://doi.org/10.3133/sir20265124.","productDescription":"Report: xi, 105 p.; Data Release; Dataset; 44 Oversize Map Figures: 17 x 11 inches","numberOfPages":"122","onlineOnly":"Y","additionalOnlineFiles":"Y","ipdsId":"IP-173988","costCenters":[{"id":36532,"text":"Central Midwest Water Science Center","active":true,"usgs":true}],"links":[{"id":500359,"rank":9,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_119211.htm","linkFileType":{"id":5,"text":"html"}},{"id":500080,"rank":5,"type":{"id":39,"text":"HTML Document"},"url":"https://pubs.usgs.gov/publication/sir20265124/full"},{"id":500083,"rank":8,"type":{"id":34,"text":"Image Folder"},"url":"https://pubs.usgs.gov/sir/2026/5124/images/"},{"id":500082,"rank":7,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/P1XUN9A8","text":"USGS data release","linkHelpText":"Bathymetry and velocity data from surveys at highway bridges crossing the Missouri River in Kansas City, Missouri, August 8–9, 2023"},{"id":500076,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/sir/2026/5124/coverthb.jpg"},{"id":500077,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/sir/2026/5124/sir20265124.pdf","text":"Report","size":"31 MB","linkFileType":{"id":1,"text":"pdf"},"description":"SIR 2026-5124"},{"id":500078,"rank":3,"type":{"id":31,"text":"Publication XML"},"url":"https://pubs.usgs.gov/sir/2026/5124/sir20265124.XML"},{"id":500079,"rank":4,"type":{"id":29,"text":"Figure"},"url":"https://pubs.usgs.gov/sir/2026/5124/downloads/","text":"Oversize figures","linkFileType":{"id":1,"text":"pdf"}},{"id":500081,"rank":6,"type":{"id":28,"text":"Dataset"},"url":"https://doi.org/10.5066/F7P55KJN","text":"USGS National Water Information System database","linkHelpText":"- USGS water data for the Nation"}],"country":"United States","state":"Kansas, Missouri","city":"Kansas City","otherGeospatial":"Missouri River","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -94.667,\n 39.2\n ],\n [\n -94.23,\n 39.2\n ],\n [\n -94.23,\n 39.07\n ],\n [\n -94.667,\n 39.07\n ],\n [\n -94.667,\n 39.2\n ]\n ]\n ]\n }\n }\n ]\n}","contact":"Director, Central Midwest Water Science Center
U.S. Geological Survey
1400 Independence Road
Rolla, MO 65401
Water users in Elbert County, Colorado, rely on groundwater from bedrock aquifers in the Denver Basin aquifer system (upper Dawson, lower Dawson, Denver, Arapahoe, and Laramie-Fox Hills aquifers) for approximately half of their water uses. Withdrawals from the bedrocks aquifers have increased to meet the water use needs of expanding regional population growth and development. The U.S. Geological Survey, in cooperation with the Elbert County Board of County Commissioners, began a study in 2015 to monitor groundwater levels within Elbert County. The primary purpose of this report is to present a summary of groundwater levels measured during the study period (2015–23) and present results from statistical analyses of changes in groundwater-level elevations through time.
Discrete groundwater levels were measured at 36 wells within Elbert County. Seven of those wells contained equipment to make and record continuous groundwater-level measurements at hourly intervals. All aquifers, except the lower Dawson aquifer, had only declining groundwater-level elevations in discrete measurements for wells with statistically significant trends. Of the eight statistically significant trends in the lower Dawson aquifer, two wells indicated increasing groundwater-level elevation from discrete measurements. The groundwater-level elevation trend medians in the upper Dawson, lower Dawson, Denver, Arapahoe, and Laramie-Fox Hills aquifers were −0.23, −0.66, −0.64, −0.39, and −0.63 feet per year, respectively, for discrete groundwater-level elevation measurements. Trends in continuous groundwater-level elevations were in agreement with statistically significant trends in discrete groundwater-level elevations for all wells. The groundwater-level elevation trend medians in this study, compared to the overall trends in a 2015−2018 study, both indicated declining groundwater-level elevations except in the upper Dawson aquifer, where the trend direction was opposite, a positive trend from 2015 to 2018 and a negative trend (declining groundwater elevations) from 2015 to 2023. The change in trends within the upper Dawson aquifer may be affected by differences in the study period and the trend analysis applied. Trends during the 2015–23 study period were compared to departures from the median 2015 groundwater-level elevation for each site in each aquifer. In general, the departures from the 2015 median supported trends observed at each site and correlated spatially with greater departures near the western border of Elbert County. Additionally, 30-year precipitation data showing wet and dry periods were overlaid with the departure from the 2015 median to assess groundwater-level patterns in wells in the five aquifers. Departures from the 2015 median groundwater-level elevations appeared greatest during the dry period between 2020 and 2023. Potentiometric-surface maps of the upper and lower Dawson aquifers created from static April 2023 groundwater elevations indicated groundwater-flow direction is generally from the south to the north. Results of this study could be used to guide additional groundwater monitoring in Elbert County and could aid in long-term planning of water resources.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston VA","doi":"10.3133/sir20265115","collaboration":"Prepared in cooperation with the Elbert County Board of County Commissioners","usgsCitation":"Palko, K.M., Russell, C.A., and Pieseski, N.J., 2026, Groundwater-level elevations in the bedrock aquifers of the Denver Basin aquifer system, Elbert County, Colorado, 2015–23: U.S. Geological Survey Scientific Investigations Report 2026–5115, 41 p., https://doi.org/10.3133/sir20265115.","productDescription":"Report: vii, 41 p.; Database","onlineOnly":"Y","ipdsId":"IP-162981","costCenters":[{"id":191,"text":"Colorado Water Science Center","active":true,"usgs":true}],"links":[{"id":499285,"rank":5,"type":{"id":31,"text":"Publication XML"},"url":"https://pubs.usgs.gov/sir/2026/5115/sir20265115.xml"},{"id":499284,"rank":4,"type":{"id":34,"text":"Image Folder"},"url":"https://pubs.usgs.gov/sir/2026/5115/images"},{"id":499210,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/sir/2026/5115/coverthb.jpg"},{"id":499211,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/sir/2026/5115/sir20265115.pdf","text":"Report","size":"13.5 MB","linkFileType":{"id":1,"text":"pdf"},"description":"SIR 2026-5115"},{"id":499212,"rank":3,"type":{"id":9,"text":"Database"},"url":"https://doi.org/10.5066/F7P55KJN","linkHelpText":"USGS Water Data for the Nation: U.S. Geological Survey National Water Information System database"},{"id":499446,"rank":6,"type":{"id":39,"text":"HTML Document"},"url":"https://pubs.usgs.gov/publication/sir20265115/full","text":"Report","linkFileType":{"id":5,"text":"html"},"description":"SIR 2026-5115"},{"id":499601,"rank":7,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_119172.htm","linkFileType":{"id":5,"text":"html"}}],"country":"United States","state":"Colorado","county":"Elbert County","geographicExtents":"{\"type\":\"FeatureCollection\",\"features\":[{\"type\":\"Feature\",\"geometry\":{\"type\":\"Polygon\",\"coordinates\":[[[-103.7126,39.5649],[-103.713,39.4761],[-103.7135,39.3876],[-103.7138,39.3011],[-103.7136,39.2136],[-103.7145,39.1265],[-103.7211,39.1266],[-103.722,39.0401],[-103.7201,38.9503],[-103.7186,38.8655],[-103.8315,38.867],[-103.9414,38.8666],[-104.0549,38.8666],[-104.0544,38.9528],[-104.0538,39.0407],[-104.0521,39.1264],[-104.166,39.1277],[-104.2733,39.1278],[-104.3854,39.1284],[-104.4958,39.1298],[-104.6072,39.1307],[-104.6642,39.1308],[-104.6638,39.2165],[-104.664,39.3026],[-104.663,39.3892],[-104.6626,39.4762],[-104.6627,39.5665],[-104.6054,39.5663],[-104.5374,39.5655],[-104.4927,39.5636],[-104.4891,39.5636],[-104.4742,39.5629],[-104.3841,39.5627],[-104.3763,39.5631],[-104.2695,39.5639],[-104.2647,39.5638],[-104.1602,39.5646],[-104.1543,39.565],[-104.0468,39.5652],[-104.0427,39.5651],[-103.9305,39.5646],[-103.9293,39.5646],[-103.8189,39.5646],[-103.8129,39.5649],[-103.7126,39.5649]]]},\"properties\":{\"name\":\"Elbert\",\"state\":\"CO\"}}]}","contact":"Director, Colorado Water Science Center
U.S. Geological Survey
Box 25046, Mail Stop 415
Denver, CO 80225
The San Francisco Bay and Sacramento–San Joaquin Delta Estuary (hereafter, Bay-Delta) is the largest estuary on the West Coast of the United States. The Bay- Delta covers more than 1,600 square miles and drains a watershed of more than 75,000 square miles, which is greater than 40 percent of California. The region surrounding the Bay- Delta is home to about 10 million people, and its habitats (fig. 1) support more than 800 plant and animal species. The waterways of the Bay- Delta are the central hub of California’s extensive freshwater delivery system, supplying water to more than 27 million Californians and 4 million acres of farmland in the Central Valley.
The U.S. Geological Survey (USGS) is the primary science agency of the U.S. Department of the Interior, providing a broad range of Earth, water, biological, and mapping data and expertise to inform natural resource management across the country. This fact sheet focuses on research conducted by the USGS in the Bay- Delta region, mostly within the past 5 years. The fact sheet is organized across five major themes: water flow and water quality, fish and wildlife, wetland restoration, invasive species, and hazards. In each of these areas, the USGS works closely with Federal, State, and local agencies; academia; and non- governmental organizations to provide objective, evidence-based science. The data and knowledge gained from USGS research and monitoring are publicly available and are routinely used by agencies, including the U.S. Bureau of Reclamation, U.S. Army Corps of Engineers, U.S. Fish and Wildlife Service, California Department of Water Resources, California Department of Fish and Wildlife, California State Water Resources Control Board, Delta Stewardship Council, and many additional organizations and stakeholders to inform management of the Bay- Delta region and its resources.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/fs20253058","usgsCitation":"Drexler, J.Z., and Weltzin, J.F., 2026, Recent scientific contributions by the U.S. Geological Survey in the San Francisco Bay and Sacramento–San Joaquin Delta Estuary: U.S. Geological Survey Fact Sheet 2025–3058, 6 p., https://doi.org/10.3133/fs20253058.","productDescription":"6 p.","numberOfPages":"6","onlineOnly":"Y","ipdsId":"IP-177659","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"links":[{"id":498957,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/fs/2025/3058/coverthb.jpg"},{"id":498952,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/fs/2025/3058/fs20253058.pdf","text":"Report","size":"14.3 MB","linkFileType":{"id":1,"text":"pdf"},"description":"FS 2025-3058 PDF"},{"id":498953,"rank":3,"type":{"id":39,"text":"HTML Document"},"url":"https://pubs.usgs.gov/publication/fs20253058/full","linkFileType":{"id":5,"text":"html"},"description":"FS 2025-3058 HTML"},{"id":498954,"rank":4,"type":{"id":31,"text":"Publication XML"},"url":"https://pubs.usgs.gov/fs/2025/3058/fs20253058.XML","linkFileType":{"id":8,"text":"xml"},"description":"FS 2025-3058 XML"},{"id":499139,"rank":6,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_119170.htm","linkFileType":{"id":5,"text":"html"}},{"id":498955,"rank":5,"type":{"id":34,"text":"Image Folder"},"url":"https://pubs.usgs.gov/fs/2025/3058/images"}],"country":"United States","state":"California","otherGeospatial":"Sacramento–San Joaquin Delta Estuary, San Francisco Bay","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -121.02008172785412,\n 38.8200776149005\n ],\n [\n -122.56776314124848,\n 38.8200776149005\n ],\n [\n -122.56776314124848,\n 37.19924956798722\n ],\n [\n -121.02008172785412,\n 37.19924956798722\n ],\n [\n -121.02008172785412,\n 38.8200776149005\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","contact":"Director, California Water Science Center
U.S. Geological Survey
6000 J Street, Placer Hall
Sacramento, California 95819
The U.S. Geological Survey (USGS) is the primary science agency of the U.S. Department of the Interior. In the San Francisco Bay and Sacramento–San Joaquin Delta Estuary (Bay-Delta) of California, the USGS plays a unique role in providing scientific leadership because of its broad research and monitoring capabilities, innovative methodologies for data collection and analysis, and dedication to objective and credible science. This fact sheet provides a summary of recent USGS projects across the Bay-Delta organized under five major research themes: water flow and water quality, fish and wildlife, wetland restoration, invasive species, and hazards. A key component of USGS research is close collaboration with State and Federal partners, academia, and non-governmental organizations to accomplish its goals. The research and partnerships described in this fact sheet are critical to the management of the complex natural resource issues across the Bay-Delta region of California.
","publicationDate":"2026-01-26","publicationStatus":"PW","contributors":{"authors":[{"text":"Drexler, Judith Z. 0000-0002-0127-3866 jdrexler@usgs.gov","orcid":"https://orcid.org/0000-0002-0127-3866","contributorId":167492,"corporation":false,"usgs":true,"family":"Drexler","given":"Judith","email":"jdrexler@usgs.gov","middleInitial":"Z.","affiliations":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true},{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"preferred":true,"id":954311,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Weltzin, Jake 0000-0001-8641-6645","orcid":"https://orcid.org/0000-0001-8641-6645","contributorId":365438,"corporation":false,"usgs":false,"family":"Weltzin","given":"Jake","affiliations":[{"id":87138,"text":"formerly Senior Science Advisor, EMA, USGS, now retired.","active":true,"usgs":false}],"preferred":false,"id":954312,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70272701,"text":"fs20253055 - 2026 - FluOil—A tool for estimating the transport and deposition of oil-particle aggregates in rivers","interactions":[],"lastModifiedDate":"2026-02-03T17:05:03.22053","indexId":"fs20253055","displayToPublicDate":"2026-01-07T07:29:50","publicationYear":"2026","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":313,"text":"Fact Sheet","code":"FS","onlineIssn":"2327-6932","printIssn":"2327-6916","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"2025-3055","displayTitle":"FluOil—A Tool for Estimating the Transport and Deposition of Oil-Particle Aggregates in Rivers","title":"FluOil—A tool for estimating the transport and deposition of oil-particle aggregates in rivers","docAbstract":"The FluOil tool was developed to help with planning and early response for oil spills in rivers where subsurface oil-sediment interactions result in the formation of oil-particle aggregates (OPA). The turbulence and variable velocity associated with water flowing within a natural stream channel creates the conditions needed for an oil slick to break up into small droplets and mix in the water column, collide with sediment or organic detritus, and form OPA. This process is similar to what occurs due to wave action along a shoreline. The FluOil tool estimates how fast OPA travel downstream in rivers as well as when and where they may deposit. The FluOil tool relies on pre-existing channel hydraulic data along with user-specified OPA characteristics of size, settling velocity and critical shear stress to compute OPA transport. It is important to know where OPA are transported and accumulated for understanding potential impacts on drinking water intakes, burial of sensitive habitat beds, potential toxicity to benthic organisms, and prolonged sheening from resuspension and breakup. OPA tend to accumulate with fine-grained (silt and clay) sediment deposits (“mud” or “muck”) in backwater areas, oxbows, side channels, pools, and other slow-moving reaches of rivers during low flows. Deposited OPA can be resuspended during high flows, driving continued environmental impact concerns that may extend beyond typical oil spill response timelines.","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/fs20253055","collaboration":"Prepared in cooperation with the Inland Oil Spill Preparedness Program, U.S. Environmental Protection Agency, Lake Superior State University, and Natural Resources Canada","usgsCitation":"Fitzpatrick, F., Roland, C., Vaughan, A., Zhu, Z., Soong, D., and Sortor, R., 2026, FluOil—A tool for estimating the transport and deposition of oil-particle aggregates in rivers: U.S. Geological Survey Fact Sheet 2025–3055, 6 p., https://doi.org/10.3133/fs20253055.","productDescription":"Report: 6 p.; Data Release","numberOfPages":"6","onlineOnly":"N","additionalOnlineFiles":"N","ipdsId":"IP-178930","costCenters":[{"id":606,"text":"Upper Midwest Environmental Sciences Center","active":true,"usgs":true},{"id":36532,"text":"Central Midwest Water Science Center","active":true,"usgs":true},{"id":37947,"text":"Upper Midwest Water Science Center","active":true,"usgs":true}],"links":[{"id":497094,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/fs/2025/3055/fs20253055.pdf","text":"Report","size":"2.04 MB","linkFileType":{"id":1,"text":"pdf"},"description":"FS 2025–3055"},{"id":497093,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/fs/2025/3055/coverthb.jpg"},{"id":497101,"rank":6,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/P99MJ6MD","text":"USGS data release","linkHelpText":"FluOil model and related datasets for Kalamazoo River, Michigan, oil spill—July 21 to October 31, 2010"},{"id":497100,"rank":5,"type":{"id":39,"text":"HTML Document"},"url":"https://pubs.usgs.gov/publication/fs20253055/full","text":"Report","description":"FS 2025–3055 HTML"},{"id":497099,"rank":4,"type":{"id":34,"text":"Image Folder"},"url":"https://pubs.usgs.gov/fs/2025/3055/images"},{"id":497098,"rank":3,"type":{"id":31,"text":"Publication XML"},"url":"https://pubs.usgs.gov/fs/2025/3055/fs20253055.XML","linkFileType":{"id":8,"text":"xml"}}],"contact":"Director, Upper Midwest Water Science Center
U.S. Geological Survey
8505 Research Way
Middleton, WI 53562
The FluOil tool helps oil spill planners and responders estimate how fast and far oiled sediment (called oil-particle aggregates [OPA]) can travel in rivers during an oil spill, and where it may settle out on the riverbed. The user interface makes it easy to run the tool for a range of river flow conditions and OPA characteristics.
","publicationDate":"2026-01-07","publicationStatus":"PW","contributors":{"authors":[{"text":"Fitzpatrick, Faith 0000-0002-9748-7075","orcid":"https://orcid.org/0000-0002-9748-7075","contributorId":209191,"corporation":false,"usgs":true,"family":"Fitzpatrick","given":"Faith","affiliations":[{"id":37947,"text":"Upper Midwest Water Science Center","active":true,"usgs":true}],"preferred":true,"id":951366,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Roland, Collin 0000-0003-1004-0746","orcid":"https://orcid.org/0000-0003-1004-0746","contributorId":343660,"corporation":false,"usgs":true,"family":"Roland","given":"Collin","affiliations":[{"id":37947,"text":"Upper Midwest Water Science Center","active":true,"usgs":true}],"preferred":true,"id":951367,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Vaughan, Angus 0000-0001-9900-4658","orcid":"https://orcid.org/0000-0001-9900-4658","contributorId":302333,"corporation":false,"usgs":true,"family":"Vaughan","given":"Angus","affiliations":[{"id":606,"text":"Upper Midwest Environmental Sciences Center","active":true,"usgs":true}],"preferred":true,"id":951368,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Zhu, Zhenduo","contributorId":340263,"corporation":false,"usgs":false,"family":"Zhu","given":"Zhenduo","affiliations":[{"id":81528,"text":"Tsinghua University, Beijing, China","active":true,"usgs":false}],"preferred":false,"id":951369,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Soong, David 0000-0003-0404-2163","orcid":"https://orcid.org/0000-0003-0404-2163","contributorId":206523,"corporation":false,"usgs":true,"family":"Soong","given":"David","affiliations":[{"id":35680,"text":"Illinois-Iowa-Missouri Water Science Center","active":true,"usgs":true}],"preferred":true,"id":951370,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Sortor, Rachel 0000-0002-8778-4383","orcid":"https://orcid.org/0000-0002-8778-4383","contributorId":298591,"corporation":false,"usgs":true,"family":"Sortor","given":"Rachel","affiliations":[{"id":36532,"text":"Central Midwest Water Science Center","active":true,"usgs":true}],"preferred":true,"id":951371,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70272788,"text":"sir20255101 - 2025 - Evaluating hydrologic data products for scientific and management applications related to potential future streamflow conditions in the Upper Mississippi and Illinois Rivers","interactions":[],"lastModifiedDate":"2026-02-05T20:25:34.834239","indexId":"sir20255101","displayToPublicDate":"2025-12-31T07:02:59","publicationYear":"2025","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":334,"text":"Scientific Investigations Report","code":"SIR","onlineIssn":"2328-0328","printIssn":"2328-031X","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"2025-5101","displayTitle":"Evaluating Hydrologic Data Products for Scientific and Management Applications Related to Potential Future Streamflow Conditions in the Upper Mississippi and Illinois Rivers","title":"Evaluating hydrologic data products for scientific and management applications related to potential future streamflow conditions in the Upper Mississippi and Illinois Rivers","docAbstract":"The hydrology of the Upper Mississippi and Illinois Rivers is a fundamental driver of ecosystem patterns and processes across a large portion of the United States. Quantitative hydrologic data for the main stems of these rivers underlie numerous scientific investigations, statistical models, and decision-making processes for local, State, and Federal agencies involved in the Upper Mississippi River Restoration program. Although historical hydrologic data exist, data representing potential future conditions of the Upper Mississippi and Illinois Rivers lack the resolution necessary to anticipate biotic and abiotic responses to altered hydrology and to determine resilient management actions. A source of future hydrologic scenarios is the readily available LOCA–VIC–mizuRoute hydrologic data products (named for the chain of models the data are produced from—localized constructed analogs, Variable Infiltration Capacity macroscale hydrological model, and the mizuRoute hydrologic routing model—that we shorten further to LVM in this report) that include simulated discharges for historic and future timeframes. The objective of this study is to assess the reliability of the hydrologic data products for their use in Upper Mississippi River Restoration program applications. Key study questions are (1) do the hydrologic data products reproduce characteristics of hydrology necessary to support ecological modeling and restoration decision-making applications within the Upper Mississippi River Restoration program? and (2) are there geographic differences in the reliability of the hydrologic data products?
Seven characteristics of river hydrology were selected related to flow magnitude, seasonality, and regime for evaluation. The seven characteristics were calculated using observed and historical simulated hydrologic data at 19 U.S. Geological Survey streamgages throughout the basins of the Upper Mississippi and Illinois Rivers; two streamgages are located on the main stem of the Mississippi River and two streamgages are located on the main stem of the Illinois River. Statistical comparisons between observed and historical simulated characteristics indicated that the hydrologic data products did not reliably represent historical hydrologic conditions in the basin or main stem. The hydrologic data products we evaluated could not reliably capture the overall hydrologic regime or flow magnitudes; the latter is evidenced by substantial underestimates of discharge at most streamgages. Seasonal hydrologic characteristics were captured more reliably than flow magnitude, but overall correspondence was low for most streamgages. A weak latitudinal pattern in seasonal characteristics indicated the hydrologic data products poorly represent streamflow timing in snow-affected regions of the basin. Discrepancies in magnitude, seasonality, and regime indicate the potential for multiple sources of error. Because poor correspondence was present across all 19 streamgages, it was not possible to identify specific drivers of poor performance (that is, drainage area or geography). The modeling chain should be evaluated for biases associated with meteorologic forcing data, as well as hydrologic model formulation and calibration.
We conclude that the hydrologic data products we evaluated appear unsuitable for applications tied to habitat and ecosystem restoration and management in the Upper Mississippi and Illinois Rivers. Plans to develop a future hydrology dataset for the Upper Mississippi River Restoration program would benefit from ongoing work to improve global climate model output downscaling methods, to improve hydrologic models, to make use of innovations in machine-learning approaches for projecting hydrology, and other efforts. The framework developed herein to evaluate hydrometeorological outputs generated using global climate models for a specific water resources application is a transferrable approach that could be applied to other data products and river systems.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20255101","collaboration":"Prepared in cooperation with the U.S. Army Corps of Engineers","usgsCitation":"Van Appledorn, M., Sawyer, L., Delaney, J., Mueller, C., Youngblood, L., Harrell, J., Breaker, B., and Frans, C., 2025, Evaluating hydrologic data products for scientific and management applications related to potential future streamflow conditions in the Upper Mississippi and Illinois Rivers: U.S. Geological Survey Scientific Investigations Report 2025–5101, 61 p., https://doi.org/10.3133/sir20255101.","productDescription":"Report: vii, 61 p.; Dataset","numberOfPages":"74","onlineOnly":"Y","additionalOnlineFiles":"N","ipdsId":"IP-168496","costCenters":[{"id":606,"text":"Upper Midwest Environmental Sciences Center","active":true,"usgs":true}],"links":[{"id":497212,"rank":5,"type":{"id":34,"text":"Image Folder"},"url":"https://pubs.usgs.gov/sir/2025/5101/images"},{"id":497211,"rank":4,"type":{"id":31,"text":"Publication XML"},"url":"https://pubs.usgs.gov/sir/2025/5101/sir20255101.XML","linkFileType":{"id":8,"text":"xml"}},{"id":497210,"rank":3,"type":{"id":39,"text":"HTML Document"},"url":"https://pubs.usgs.gov/publication/sir20255101/full","linkFileType":{"id":5,"text":"html"}},{"id":499598,"rank":7,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_119153.htm","linkFileType":{"id":5,"text":"html"}},{"id":497239,"rank":6,"type":{"id":28,"text":"Dataset"},"url":"https://doi.org/10.5066/F7P55KJN","text":"USGS National Water Information System database","linkHelpText":"- USGS water data for the Nation"},{"id":497207,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/sir/2025/5101/coverthb.jpg"},{"id":497208,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/sir/2025/5101/sir20255101.pdf","text":"Report","size":"5.91 MB","linkFileType":{"id":1,"text":"pdf"},"description":"SIR 2025–5051"}],"country":"United States","state":"Illinois, Indiana, Iowa, Minnesota, Missouri, South Dakota, Wisconsin","otherGeospatial":"Upper Mississippi and Illinois Rivers","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -95.22471535622894,\n 47.665636098460055\n ],\n [\n -96.33347677420088,\n 46.199243414391816\n ],\n [\n -98.31270934097893,\n 45.87559838036478\n ],\n [\n -94.41776106593042,\n 40.4616759608773\n ],\n [\n -92.16087186224964,\n 36.96306941324279\n ],\n [\n -88.4774787487018,\n 36.50634300187468\n ],\n [\n -86.96280550173634,\n 41.463056598324656\n ],\n [\n -88.07530637371752,\n 42.73486591964032\n ],\n [\n -88.68694421055064,\n 45.85608340482759\n ],\n [\n -95.22471535622894,\n 47.665636098460055\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","contact":"Director, Upper Midwest Environmental Sciences Center
U.S. Geological Survey
2630 Fanta Reed Road
La Crosse, Wisconsin 54603
In April 2021, a synoptic study conducted by the U.S. Geological Survey (USGS) and National Park Service (NPS) identified wastewater-related contaminants of emerging concern (CECs) in springs along the South Rim of the Grand Canyon. These springs are located north of Bright Angel Wash, an ephemeral channel that receives treated effluent from the South Rim Wastewater Treatment Plant (SRWTP). Although water flows southwest and away from the canyon, there is evidence that treated wastewater is finding a flow path along fractures associated with the Bright Angel Fault back to water sources along the South Rim.
The CECs identified during the April 2021 sampling included several per- and polyfluoroalkyl substances (PFAS) and pharmaceutical compounds. The PFAS compounds detected only consisted of perfluoroalkyl acids, and these were only detected at Bright Angel Wash (treated wastewater), Monument Spring, and upper Horn Bedrock Spring. The other five sampled springs (the Salt Creek, Horn East Alluvium, Garden, Pumphouse, and Pipe Springs) had no detections of PFAS compounds. The five perfluoroalkyl acids detected at Monument Spring (in descending order of concentration) were perfluorobutanesulfonic acid (PFBS), perfluoropentanoic acid, perfluorooctanoic acid, perfluorohexanoic acid, and perfluorooctanesulfonic acid. Only the short-chained PFBS and perfluorobutanoic acid compounds were detected at the upper Horn Bedrock Spring. All the same perfluoroalkyl acids were found at Bright Angel Wash, except for PFBS.
Monument Spring was the only spring to have detections of pharmaceuticals. The two pharmaceuticals detected at the highest concentrations at Monument Spring were diphenhydramine (antihistamine) and carbamazepine (anticonvulsant or anti-epileptic drug). The other detected pharmaceuticals included (in descending order of concentration) fluconazole (antifungal), sulfamethoxazole (antibiotic), metformin (diabetes drug), tramadol (opioid analgesic), and venlafaxine (antidepressant and nerve pain medication). The same pharmaceuticals were detected in the wastewater at Bright Angel Wash but in greater concentrations. No CEC concentrations measured at Monument Spring exceeded any drinking water standards or human health benchmarks; however, most of the compounds detected have no regulatory standards. Studies of the ecological effects of these compounds show that some of the compounds detected can have endocrine and physiological effects, but generally, effects were observed at concentrations multiple orders of magnitude greater than what was measured during the April 2021 study.
Data from 1980 through 2022 retrieved from the Water Quality Portal were combined with data from the one-time synoptic sampling in April 2021 to assess the usefulness of other analytes for identifying a wastewater connection to South Rim springs. Most of the historical water chemistry data showed a statistical difference between samples collected within and east of the Garden Creek watershed and samples collected from locations in watersheds to the west of Garden Creek, including the Horn Creek, Salt Creek, Monument Creek, and Hermit Creek watersheds, which roughly align with the Bright Angel Fault. Most of the historical analytes were inconclusive as potential wastewater tracers, but nitrate, chloride, and gadolinium data possibly support the historical contribution of wastewater to Monument Spring.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20255095","collaboration":"Prepared in cooperation with the National Park Service, Grand Canyon National Park","usgsCitation":"Paretti, N.V., Beisner, K.R., and Shepherd, S.J.R., 2025, Assessment of treated wastewater infiltration in Bright Angel Wash and the potential for contaminants of emerging concern influencing spring water quality along the South Rim of the Grand Canyon in Grand Canyon National Park, Arizona (ver. 1.1, 2026): U.S. Geological Survey Scientific Investigations Report 2025–5095, 59 p., https://doi.org/10.3133/sir20255095.","productDescription":"ix, 59 p.","numberOfPages":"59","onlineOnly":"Y","additionalOnlineFiles":"N","ipdsId":"IP-159478","costCenters":[{"id":128,"text":"Arizona Water Science Center","active":true,"usgs":true}],"links":[{"id":499495,"rank":7,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_119152.htm","linkFileType":{"id":5,"text":"html"}},{"id":499484,"rank":6,"type":{"id":25,"text":"Version History"},"url":"https://pubs.usgs.gov/sir/2025/5095/versionHist.txt","linkFileType":{"id":2,"text":"txt"},"description":"SIR 2025-5095 Version History"},{"id":497774,"rank":4,"type":{"id":31,"text":"Publication XML"},"url":"https://pubs.usgs.gov/sir/2025/5095/sir20255095.XML","linkFileType":{"id":8,"text":"xml"},"description":"SIR 2025-5095 XML"},{"id":497773,"rank":3,"type":{"id":39,"text":"HTML Document"},"url":"https://pubs.usgs.gov/publication/sir20255095/full","linkFileType":{"id":5,"text":"html"},"description":"SIR 2025-5095 HTML"},{"id":497772,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/sir/2025/5095/sir20255095.pdf","size":"11.6 MB","linkFileType":{"id":1,"text":"pdf"},"description":"SIR 2025-5095 PDF"},{"id":497775,"rank":5,"type":{"id":34,"text":"Image Folder"},"url":"https://pubs.usgs.gov/sir/2025/5095/images/"},{"id":497771,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/sir/2025/5095/coverthb2.jpg"}],"country":"United States","state":"Arizona","otherGeospatial":"Bright Angel Wash, Grand Canyon","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -112.25,\n 36.1\n ],\n [\n -112.25,\n 35.94693133579284\n ],\n [\n -112,\n 35.94693133579284\n ],\n [\n -112,\n 36.1\n ],\n [\n -112.25,\n 36.1\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","edition":"Version 1.0: December 29, 2025; Version 1.1: February 3, 2026","contact":"Director, Arizona Water Science Center
U.S. Geological Survey
520 N. Park Avenue, Suite 221
Tucson, AZ 85719
The relation between the groundwater and the amount of natural recharge to the Cahuilla Valley and Terwilliger Valley groundwater basins is not well understood. During the 20th century, the reliance on groundwater near Anza, California, used for agricultural, domestic, and municipal reasons has increased, and there is the potential for changes in groundwater availability related to climate change. Several types of existing data were evaluated, and new data were collected for this study, with the goal of characterizing the region’s hydrogeology. The study’s scope included constructing a geologic framework model to show where the groundwater-bearing units are present and their relation to each other, estimating the major components of the groundwater budget, and understanding local short-term and regional long-term groundwater flow and how that has changed since the early 1900s.
Two electrical resistivity tomography surveys were done in the Durasno Valley about 2,150 feet apart to identify the thickness of the alluvium, its horizontal extent, and the depth-to-basement along two profiles perpendicular to Cahuilla Creek. The subsurface sediments were mostly horizontally layered and the transitional boundary between the alluvium and basement was thinner and shallower along the upgradient profile where the depth-to-basement was about 70 feet below land surface; the depth-to-basement at the downgradient profile was more than about 140 feet below land surface. The results from the surveys were used to place four monitoring wells at two sites along the survey profiles. Artesian flow from the deepest well at the downgradient site indicated that the decomposed and competent basement likely contributed some groundwater to the overlying alluvium, laterally, from below, or both.
A digital three-dimensional geologic framework model was constructed using EarthVision software to represent the subsurface geometry of the alluvium, decomposed basement, and competent basement. Maps and cross sections of the modeled thicknesses of the alluvium and decomposed basement, and the modeled elevation of the top of the competent basement, were made to show the subsurface geometry of vertical faults, selected wells, and the groundwater-bearing units.
Because natural recharge is related to the variable cycles of precipitation, estimates are difficult to quantify. Recharge and runoff have extreme interannual variability in the study area; recharge and runoff can be sporadic, and a substantive amount may not occur in some years. Estimates of recharge from a previous study and the regional-scale Basin Characterization Model for California for four different periods ranged from 3,800 acre-feet/year for 1897–1947 to 5,900 acre-feet/year for 1971–2000. Potential recharge from the disposal of domestic septic systems may have been as much as 500 acre-feet in 2020. It was estimated that between about 400 and 2,400 acre-feet/year of groundwater is lost through evapotranspiration by vegetation and evaporation from open water bodies, but the main source of discharge is through pumpage, mainly used for agriculture from the alluvium in the Cahuilla Valley and Terwilliger Valley groundwater basins. The estimated total pumpage for 1991–2021 ranged from about 1,140 acre-feet in 2019 to about 3,450 acre-feet in 1994. When summed, the cumulative amount of estimated pumpage between 1991 and 2021 was about 81,400 acre-feet.
The general direction of groundwater flow is from the northeast along the San Jacinto fault zone at the headwaters of Cahuilla and Hamilton Creeks, to the surface-water outlets at the west and southeast parts of the study area. Groundwater-level data from the 1950s and earlier indicate that there was a natural groundwater divide between the Cahuilla Valley and Terwilliger Valley groundwater basins, but the changing magnitude and extent of the groundwater depressions caused by pumping since about 1950 indicate that the location of the natural groundwater boundary between the Cahuilla Valley and Terwilliger Valley groundwater basins has migrated over time.
Flow from the upper to the lower parts of the Cahuilla Valley groundwater basin roughly follows the course of Cahuilla Creek through the narrow Durasno Valley where an estimated volume of flow in April 2019 was about 10–150 acre-feet/year. Short-term trends in groundwater levels, particularly in wells where groundwater is shallow and in the basement unit, show how some areas respond quickly to recharge and discharge. Wells located further to the east within the Cahuilla Valley groundwater basin in the alluvium show much less of a response to recharge events; areas of sustained pumpage from the alluvium, primarily for agriculture, show long-term declines in groundwater levels and generally do not show the effects of storm events or recent runoff. Groundwater levels in wells that are farthest from where most of the recharge occurs and where pumping has been the greatest, had some of the largest long-term groundwater-level declines at a rate of about 0.8 foot/year between 1971 and 2021.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20255073","collaboration":"Prepared in cooperation with the Ramona Band of Cahuilla","usgsCitation":"Stamos, C.L., Christensen, A.H., Cromwell, G., Dick, M.C., Ely, C.P., Jachens, E.R., Ogle, S.E., and Shepherd, M.M., 2025, Hydrogeologic characterization of the Cahuilla Valley and Terwilliger Valley Groundwater Basins,\nRiverside County, California: U.S. Geological Survey Scientific Investigations Report 2025–5073, 65 p., https://doi.org/10.3133/sir20255073.","productDescription":"Report: ix, 65 p., 3 Data Releases","onlineOnly":"Y","ipdsId":"IP-116466","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"links":[{"id":497529,"rank":5,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/P93KA4IG","text":"USGS data release","description":"USGS data release","linkHelpText":"Select borehole data for Anza Valley, Anza, CA"},{"id":497531,"rank":7,"type":{"id":34,"text":"Image Folder"},"url":"https://pubs.usgs.gov/sir/2025/5073/images"},{"id":497875,"rank":9,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_119059.htm","linkFileType":{"id":5,"text":"html"}},{"id":497532,"rank":8,"type":{"id":31,"text":"Publication XML"},"url":"https://pubs.usgs.gov/sir/2025/5073/sir20255073.XML"},{"id":497530,"rank":6,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/P9DJLSOV","text":"USGS data release","description":"USGS data release","linkHelpText":"Hydrogeologic data from the Cahuilla Valley and Terwilliger Valley groundwater basins, Riverside County, California, 2022 (ver. 2.0, August 2025)"},{"id":497528,"rank":4,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/P9LCEHD7","text":"USGS data release","description":"USGS data release","linkHelpText":"Electrical resistivity tomography in the Anza-Terwilliger Valley, Riverside County, California 2018"},{"id":497527,"rank":3,"type":{"id":39,"text":"HTML Document"},"url":"https://pubs.usgs.gov/publication/sir20255073/full","text":"Report","linkFileType":{"id":5,"text":"html"},"description":"SIR 2025-5073"},{"id":497526,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/sir/2025/5073/sir20255073.pdf","text":"Report","size":"15.4 MB","linkFileType":{"id":1,"text":"pdf"},"description":"SIR 2025-5073"},{"id":497525,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/sir/2025/5073/coverthb.jpg"}],"country":"United States","state":"California","otherGeospatial":"Cahuilla Valley and Terwilliger Valley groundwater basins","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -117.5,\n 33.8\n ],\n [\n -117.5,\n 33\n ],\n [\n -115.8,\n 33\n ],\n [\n -115.8,\n 33.8\n ],\n [\n -117.5,\n 33.8\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","contact":"Director, California Water Science Center
U.S. Geological Survey
6000 J Street, Placer Hall
Sacramento, California 95819
This 1:5,000,000-scale geologic map of the Guinevere Planitia quadrangle divides the region into 15 geologic material units, defined using Magellan synthetic aperture radar (12.6-centimeter-wavelength radar system; 75 meters per pixel) datasets and including upland terrain units (2.4 percent of the surface area), plains materials units (59 percent), flow materials associated with named and unnamed eruptive centers (37.2 percent), small volcanic edifices, and impact crater materials (1.4 percent). Upland terrain units consist of tessera and lineated upland material, plains materials consist of Guinevere regional plains and Guinevere lineated and mottled plains, and flow materials consist of lobate flow material and plains-forming flow material. Specific lobate flows associated with Atanua Mons, Tuli Mons, Var Mons, and Uilata Fluctus are mapped separately. Other mapped units are impact crater material and small volcanic edifice. In addition to geologic units, we mapped linear features that show patterns of deformation or flow across the quadrangle. These consist of faults, wrinkle ridges, broad arches, channels, troughs, and flow direction indicators. The map region also contains several small volcanic features: shields, depressions, and craters. These, in combination with the plains, large volcanoes, and coronae, show the pervasive influence of volcanism across Venusian lowlands. The rims of nine identified impact features are delineated; large bright and dark haloes, which in some cases are associated with individual impact craters, are mapped as surficial mantling deposits.
We documented spatial relationships using the stratigraphic and cross-cutting relationships of the quadrangle’s geologic units and features to provide a synthesis of the region’s geologic history. The upland terrain of the quadrangle indicates intense tectonic deformation and uplift. It is exposed as embayed remnants, typically within the plains, and represents the oldest geologic materials locally and across the region. Guinevere plains and the plains-forming flow unit appear to be assemblages of volcanic flows from multiple sources, including distinct coronae and corona-like structures. The temporal evolution of Guinevere lineated and mottled plains was likely protracted, with continued formation of small volcanic edifices over a long period. The morphologic and radar brightness characteristics of volcanoes in the region indicate their growth may have involved (1) multiple large-scale eruptive centers with recognizable spatial and temporal sequences, (2) extensive lava flow fields with a multitude of flows producing complex, overlapping patterns, and (3) numerous small volcanic edifices, including shields, domes, and cones. Although geologic patterns common to other regions of Venus are evident in the Guinevere Planitia quadrangle, local relative age relationships are inconsistent or unclear, preventing robust stratigraphic correlation. The mapping results do, however, indicate complicated local sequences of volcanic and tectonic activity.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sim3539","collaboration":"Prepared for the National Aeronautics and Space Administration","usgsCitation":"Crown, D.A., Stofan, E.R., Bleamaster, L.F., III, 2025, Geologic map of the Guinevere Planitia quadrangle (V–30), Venus: U.S. Geological Survey Scientific Investigations Map 3539, 1 sheet, scale 1:5,000,000, pamphlet 15 p., https://doi.org/10.3133/sim3539.","productDescription":"Pamphlet: iv, 15 p.; 1 Sheet: 52.76 x 35.57 inches; Read Me; Database; Metadata","onlineOnly":"N","additionalOnlineFiles":"Y","ipdsId":"IP-101507","costCenters":[{"id":131,"text":"Astrogeology Science Center","active":true,"usgs":true}],"links":[{"id":497754,"rank":6,"type":{"id":9,"text":"Database"},"url":"https://pubs.usgs.gov/sim/3539/database","text":"Database"},{"id":497753,"rank":5,"type":{"id":20,"text":"Read Me"},"url":"https://pubs.usgs.gov/sim/3539/sim3539_readme.txt","size":"4 KB","linkFileType":{"id":2,"text":"txt"}},{"id":497752,"rank":4,"type":{"id":16,"text":"Metadata"},"url":"https://pubs.usgs.gov/sim/3539/sim3539_metadata.xml","size":"16 KB","linkFileType":{"id":8,"text":"xml"}},{"id":497751,"rank":3,"type":{"id":26,"text":"Sheet"},"url":"https://pubs.usgs.gov/sim/3539/sim3539_sheet.pdf","text":"Sheet","size":"14.8 MB","linkFileType":{"id":1,"text":"pdf"},"description":"SIM 3539 Sheet","linkHelpText":"- Geologic Map of the Guinevere Planitia Quadrangle (V–30), Venus"},{"id":497750,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/sim/3539/sim3539_pamphlet.pdf","text":"Pamphlet","size":"1 MB","linkFileType":{"id":1,"text":"pdf"},"description":"SIM 3539 Pamphlet"},{"id":497749,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/sim/3539/coverthb.jpg"}],"scale":"5000000","otherGeospatial":"Guinevere Planitia quadrangle, Venus","contact":"Astrogeology Science Center
U.S. Geological Survey
2255 N. Gemini Dr.
Flagstaff, AZ 86001
The Mississippi Sound, an estuarine environment located between the mainland and barrier islands bordering the northern Gulf of America (formerly the Gulf of Mexico), serves as a vital ecosystem for the States of Mississippi and Alabama. Spanning approximately 100 kilometers from east to west and covering 1,400 square kilometers, the sound is home to marine industry and ports, and its shallow and brackish waters sustain a diverse array of marine life. Barrier islands along the southern edge of the sound separate the microtidal estuary from the Gulf of America. This protection from gulf wave action mediates current flow within the sound, resulting in predominantly fine-grained sediment deposition along the seafloor. This study, conducted by the U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers, provides insight on fluvial and tidal processes spanning the past 5,000 years. The report synthesizes existing research to provide a comprehensive overview of the sound geology, from Pleistocene origins to present-day morphology, and utilizes high-resolution single channel seismic profiles and sediment data to identify and map sedimentary deposits and morphologic features at and below the seafloor. Despite its ecological significance, the Mississippi Sound faces environmental challenges, including water-quality issues, habitat degradation, storm-induced erosion, and the ongoing threats of sea-level rise and environmental changes. This study uses the present-day understanding of the sound's geology to inform coastal management decisions, hazard assessment, and potential mineral resources.
Contact Us- USGS Publications Warehouse
Director, St. Petersburg Coastal and Marine Science Center
U.S. Geological Survey
600 4th Street South
St. Petersburg, FL 33701
Management practices that enhance habitat complexity in dam tailwaters often aim to increase biodiversity and improve ecosystem health. However, in other instances, management practices may simplify habitat features to help minimize the establishment of invasive species. These tradeoffs are complex, particularly in the face of drought and warming water temperatures. In Glen Canyon National Recreation Area, a backwater known as −12 Mile Slough (henceforth the Slough), located 5-kilometers downstream from Glen Canyon Dam, is being considered for removal to reduce breeding habitat for warmwater nonnative fishes. In this report, the habitat suitability for and occupancy of dragonflies and damselflies (Odonata) at the Slough are assessed. U.S. Geological Survey staff conducted three site visits to the Colorado River in Glen Canyon, the Slough, and another backwater (“Frogwater”) on September 11–13, and 26, 2024. The physical habitat of the sampling sites was characterized by recording water temperatures, specific conductance, dissolved oxygen, turbidity, flow, depth, and benthic substratum size distribution. We sampled aquatic macroinvertebrates and riparian macroinvertebrates using benthic and aerial collection methods, respectively. We describe three distinct benthic aquatic invertebrate communities in and around the Slough, two of which contained Odonata. We found no Odonata larvae in the mainstem, at Frogwater, or in the Lower Slough. Using historic specimen data from the Museum of Northern Arizona, we report 8 species of damselflies from one family (Coenagrionidae) and 8 species of dragonflies from three families (Aeshnidae, Gomphidae, and Libellulidae) in Glen Canyon between 1985 and 2024. We discuss the habitat requirements of Odonata larvae known to occur in the Slough, as well as their cultural and recreational values. We conclude that channelization of the Slough to cool water temperatures may reduce larval Odonata habitat locally but is unlikely to affect their diversity and abundance on a regional scale.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/ofr20251042","collaboration":"National Park Service, Bureau of Reclamation, Springs Stewardship Institute","usgsCitation":"Metcalfe, A.N., Ford, M.A., Stevens, L.E., and Kennedy, T.A., 2025, Assessment of dragonfly and damselfly (Odonata) occupancy and habitat suitability at −12 Mile Slough, Glen Canyon National Recreation Area, Arizona: U.S. Geological Survey Open-File Report 2025–1042, 15 p., https://doi.org/10.3133/ofr20251042.","productDescription":"Report, ix, 15 p.; Data Release","numberOfPages":"15","onlineOnly":"Y","ipdsId":"IP-173051","costCenters":[{"id":568,"text":"Southwest Biological Science Center","active":true,"usgs":true}],"links":[{"id":497289,"rank":5,"type":{"id":34,"text":"Image Folder"},"url":"https://pubs.usgs.gov/of/2025/1042/images"},{"id":497288,"rank":4,"type":{"id":31,"text":"Publication XML"},"url":"https://pubs.usgs.gov/of/2025/1042/ofr20251042.XML","description":"OFR 2025-1042 XML"},{"id":497291,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/of/2025/1042/coverthb2.jpg"},{"id":497286,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/of/2025/1042/ofr20251042.pdf","text":"Report","size":"7.28 MB","linkFileType":{"id":1,"text":"pdf"},"description":"OFR 2025-1042 PDF"},{"id":497287,"rank":3,"type":{"id":39,"text":"HTML Document"},"url":"https://pubs.usgs.gov/publication/ofr20251042/full","linkFileType":{"id":5,"text":"html"},"description":"OFR 2025-1042 HTML"},{"id":497290,"rank":6,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/P1EJXMAO","text":"USGS Data Release","linkHelpText":"Aquatic Invertebrate and Habitat Assessment in Glen Canyon and Associated Backwaters, September 2024"}],"country":"United States","state":"Arizona","otherGeospatial":"12 Mile Slough, Glen Canyon National Recreation Area","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -111.49179778654118,\n 36.90754527885582\n ],\n [\n -111.57073960910685,\n 36.90754527885582\n ],\n [\n -111.57073960910685,\n 36.8586991785957\n ],\n [\n -111.49179778654118,\n 36.8586991785957\n ],\n [\n -111.49179778654118,\n 36.90754527885582\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","contact":"Director, Southwest Biological Science Center
Grand Canyon Monitoring and Research Center
U.S. Geological Survey
2255 N Gemini Drive
Flagstaff, AZ 86001
The Lee Acres Landfill and Giant Bloomfield Refinery are adjacent properties near the City of Farmington, New Mexico, each having undergone monitoring and remediation related to historical site activities. At the landfill, site cleanup has included the installation of a capillary barrier over former liquid waste lagoons and periodic monitoring of groundwater elevations and groundwater quality. At the refinery, remediation has focused on several petrochemical and crude oil release areas and included soil excavation, groundwater treatment, and regular monitoring of groundwater elevations and quality. Groundwater at both sites has higher concentrations of volatile organic compounds and trace metals than background aquifer concentrations. In 2022, the U.S. Geological Survey compiled the Lee Acres-Giant Bloomfield Refinery Database (LAGBRD), which contains publicly available groundwater-elevation data and organic and inorganic groundwater-quality data from both sites, spanning from 1985 to 2020. Data from the LAGBRD and precipitation data from other sources were used to better understand the cause of relatively high manganese concentrations observed in some groundwater wells at the site through comparison of groundwater chemistry to chemical end members, interpretation of spatial and temporal patterns in the groundwater chemistry, and interpretation of groundwater flow properties. In this study, elevated chloride concentrations in groundwater downgradient from the landfill have been attributed to landfill leachate based on the temporal and spatial variability of chloride concentrations and chloride-to-bromide ratios. Installation of a capillary barrier and surface-water runoff controls at the landfill in 2005 appears to have altered infiltration patterns at that site, resulting in a decrease in chloride at some wells but an increase in chloride and dissolved manganese at others. The timing and relation among groundwater elevation, chloride concentration, and manganese concentration suggest that leachate stored in the vadose zone provides a continued source of contamination to groundwater.
Director, New Mexico Water Science Center
U.S. Geological Survey
6700 Edith Blvd. NE
Albuquerque, NM 87113
Contact Us- USGS Publications Warehouse
","tableOfContents":"In 2019, the U.S. Geological Survey and Wake County Environmental Services began a collaborative study to evaluate groundwater resources and long-term groundwater availability in the county’s fractured-rock groundwater system. Wake County, in central North Carolina, is experiencing rapid population growth, associated land development, and changing water use. Hydrogeologic data including groundwater levels, aquifer testing, borehole fracture flow measurements, water-quality samples, and groundwater age-dating tracers were collected, along with findings from previous investigations, to help inform a conceptual model of the flow system used to develop a modular three-dimensional finite-difference groundwater-flow model (MODFLOW) for simulating historical and future groundwater conditions from 2000 to 2070.
Hydraulic conductivity and transmissivity ranges were estimated from 17 slug tests and 21 borehole-flow measurements. Groundwater-quality analytical results from 19 sampling sites indicate that oxidation-reduction (redox) conditions varied within the regolith and bedrock and that minimal evaporation occurred before recharge entered the groundwater system. Age dating revealed mixtures of older and younger water, ranging from the 1940s to the 1990s—indicating variable flow pathways of recharge within permeable bedrock fracture zones.
To simplify the complex fractured-rock groundwater system, two layers representing the regolith and the fractured bedrock were used in the MODFLOW model. Model calibration included parameter estimation and provided a reasonable fit to observed groundwater levels and estimated stream base flows. The model forecast scenarios incorporated future climate-model data for two emissions scenarios with land cover change projections to simulate potential impacts to future groundwater levels, recharge, and base flows. Recharge and base flow projections were largely within historical ranges, with no apparent long-term trends, but did indicate a slight downward shift in median values—likely, in part, because of differences in spatial resolution of input climate datasets. Seasonal patterns were consistent with historical data, with projections of possible increases in future winter recharge. Model limitations are discussed, and additional monitoring and model refinement needs are highlighted to support decision making for local groundwater management.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20255087","issn":"2328-0328","collaboration":"Prepared in cooperation with Wake County Environmental Services","usgsCitation":"Antolino, D.J., Gonthier, G.J., and Sanchez, G.M., 2025, Simulation of groundwater flow in Wake County, North Carolina, 2000 through 2070: U.S. Geological Survey Scientific Investigations Report 2025–5087, 77 p., https://doi.org/10.3133/sir20255087.","productDescription":"Report: xii, 77 p.; 2 Data Releases","numberOfPages":"94","onlineOnly":"Y","ipdsId":"IP-141136","costCenters":[{"id":13634,"text":"South Atlantic Water Science Center","active":true,"usgs":true}],"links":[{"id":497806,"rank":8,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_119050.htm"},{"id":496949,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/sir/2025/5087/coverthb.jpg"},{"id":497076,"rank":7,"type":{"id":39,"text":"HTML Document"},"url":"https://pubs.usgs.gov/publication/sir20255087/full","linkFileType":{"id":5,"text":"html"},"description":"SIR 2025-5087 HTML"},{"id":497075,"rank":6,"type":{"id":31,"text":"Publication XML"},"url":"https://pubs.usgs.gov/sir/2025/5087/sir20255087.XML","linkFileType":{"id":8,"text":"xml"},"description":"SIR 2025-5087 XML"},{"id":496956,"rank":5,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/P9UC8F3Z","text":"USGS Data Release","linkHelpText":"- Water-level data and results for slug tests performed in 17 wells in Wake County, North Carolina, 2020 and 2021"},{"id":496955,"rank":4,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/P9N3EQ86","text":"USGS Data Release","linkHelpText":"- MODFLOW-NWT model used to simulate groundwater flow in Wake County, North Carolina, 2000 through 2070"},{"id":496950,"rank":3,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/sir/2025/5087/sir20255087.pdf","size":"21.1 MB","linkFileType":{"id":1,"text":"pdf"},"description":"SIR 2025-5087 PDF"},{"id":496958,"rank":2,"type":{"id":34,"text":"Image Folder"},"url":"https://pubs.usgs.gov/sir/2025/5087/images"}],"country":"United States","state":"North Carolina","county":"Wake County","geographicExtents":"{\"type\":\"FeatureCollection\",\"features\":[{\"type\":\"Feature\",\"geometry\":{\"type\":\"Polygon\",\"coordinates\":[[[-78.5465,36.0218],[-78.4307,35.9795],[-78.3969,35.9387],[-78.3567,35.9318],[-78.351,35.909],[-78.3385,35.9052],[-78.3347,35.8997],[-78.3302,35.896],[-78.3245,35.896],[-78.3177,35.8963],[-78.3137,35.8976],[-78.3081,35.8935],[-78.2948,35.8797],[-78.292,35.8792],[-78.2893,35.8741],[-78.2859,35.8713],[-78.2831,35.8681],[-78.2782,35.8631],[-78.2749,35.8567],[-78.2756,35.8494],[-78.2707,35.843],[-78.2657,35.8361],[-78.2652,35.8325],[-78.2613,35.8315],[-78.2591,35.826],[-78.2599,35.8183],[-78.3731,35.7523],[-78.4635,35.7072],[-78.4686,35.7087],[-78.4709,35.7078],[-78.4732,35.7046],[-78.4778,35.7011],[-78.5716,35.6255],[-78.708,35.5191],[-78.9196,35.5857],[-78.9956,35.6104],[-78.9796,35.6656],[-78.9439,35.7515],[-78.9421,35.756],[-78.9403,35.7615],[-78.9337,35.7859],[-78.9191,35.8216],[-78.9096,35.8506],[-78.9076,35.8678],[-78.89,35.8676],[-78.8298,35.8689],[-78.8056,35.9281],[-78.7609,35.9176],[-78.751,35.9307],[-78.7372,35.941],[-78.714,35.9729],[-78.7009,36.0068],[-78.6985,36.0131],[-78.7048,36.0091],[-78.7077,36.0087],[-78.7076,36.0132],[-78.7052,36.0223],[-78.7085,36.0287],[-78.7102,36.0287],[-78.713,36.0278],[-78.7164,36.0283],[-78.7232,36.0334],[-78.726,36.0343],[-78.7272,36.0334],[-78.7278,36.0289],[-78.7324,36.0267],[-78.7353,36.0199],[-78.7422,36.0209],[-78.75,36.026],[-78.7551,36.0283],[-78.7545,36.0301],[-78.7511,36.0323],[-78.7499,36.035],[-78.747,36.0395],[-78.7492,36.0427],[-78.7503,36.0468],[-78.7519,36.0491],[-78.7564,36.0532],[-78.7498,36.0718],[-78.7088,36.0768],[-78.6895,36.0752],[-78.5922,36.0378],[-78.5465,36.0218]]]},\"properties\":{\"name\":\"Wake\",\"state\":\"NC\"}}]}","contact":"Director, South Atlantic Water Science Center
U.S. Geological Survey
1770 Corporate Drive, suite 500
Norcross, GA 30093
Contact Us- USGS Publications Warehouse
","tableOfContents":"This report describes a cooperative study by the U.S. Geological Survey and Missouri Department of Natural Resources that evaluated temporal changes in total nitrogen (TN) and total phosphorus (TP) concentrations in the Lower Grand River hydrologic unit. The study focused on trends since 2010, when the basin was designated as a priority drainage basin of the Mississippi River Basin Healthy Watersheds Initiative (MRBI). At three local drainage basins within the Lower Grand hydrological unit (MRBI sites), stream nutrient trends were evaluated using flow-adjusted (FA) TN and TP concentrations for water years 2011 through 2023. FATN concentration trends were not statistically significant for any MRBI site. One site (site 2) showed a statistically significant increasing trend in FATP concentration, indicating a possible increase in phosphorus sources in parts of the basin. Overall, streamflow variability appeared to be the dominant factor affecting nutrient concentrations at MRBI sites. At five regional drainage basins, including the Grand River and nearby rivers with data from 1994 through 2023 (long-term sites), annual flow-normalized (FN) TN and TP concentrations were evaluated for trends before (water years 2000–10) and during (water years 2010–23) the MRBI. For water years 2010 through 2023, annual FNTN and FNTP concentrations decreased in the Grand River, as well as in the Nodaway and Chariton Rivers, which were not targeted by the MRBI. The Grand River (site 9) reversed from increasing to decreasing FNTP concentrations after 2010, with a 26-percent reduction. Annual FNTN and FNTP concentrations also decreased at the Missouri River sites. While nutrient reductions in the Grand River may reflect the effects of implemented conservation practices, similar trends in nearby, nontargeted rivers and the absence of strong decreasing trends at MRBI sites suggest that broader regional factors, instead of or in addition to MRBI efforts, may have contributed to nutrient reductions in the Grand River.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20255099","collaboration":"Prepared in cooperation with the Missouri Department of Natural Resources","usgsCitation":"Kamrath, B.J.W., Lauderback, C.N., and Murphy, J.C., 2025, Temporal changes in nutrient concentrations in the Lower Grand River and selected drainage basins, Missouri and Iowa, during the Mississippi River Basin Healthy Watersheds Initiative (2010–23): U.S. Geological Survey Scientific Investigations Report 2025–5099, 19 p., https://doi.org/10.3133/sir20255099.","productDescription":"Report: vii, 19 p.; 5 Linked Tables; Data Release; Dataset","numberOfPages":"32","onlineOnly":"Y","additionalOnlineFiles":"Y","ipdsId":"IP-167198","costCenters":[{"id":36532,"text":"Central Midwest Water Science Center","active":true,"usgs":true}],"links":[{"id":497801,"rank":9,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_118990.htm"},{"id":496854,"rank":7,"type":{"id":28,"text":"Dataset"},"url":"https://doi.org/10.5066/F7P55KJN","text":"USGS National Water Information System database","linkHelpText":"- USGS water data for the Nation"},{"id":496853,"rank":6,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/P13FQ2YN","text":"USGS data release","linkHelpText":"Archive of the load estimation models used in the analyses of temporal changes in nutrient concentrations in the Lower Grand River and selected drainage basins, Missouri and Iowa (2010–23)"},{"id":496855,"rank":8,"type":{"id":39,"text":"HTML Document"},"url":"https://pubs.usgs.gov/publication/sir20255099/full"},{"id":496848,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/sir/2025/5099/coverthb.jpg"},{"id":496852,"rank":5,"type":{"id":27,"text":"Table"},"url":"https://pubs.usgs.gov/sir/2025/5099/downloads/","text":"Tables 1.1 to 1.5","linkFileType":{"id":3,"text":"xlsx"}},{"id":496851,"rank":4,"type":{"id":34,"text":"Image Folder"},"url":"https://pubs.usgs.gov/sir/2025/5099/images/"},{"id":496849,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/sir/2025/5099/sir20255099.pdf","text":"Report","size":"2.4 MB","linkFileType":{"id":1,"text":"pdf"},"description":"SIR 2025-5099"},{"id":496850,"rank":3,"type":{"id":31,"text":"Publication XML"},"url":"https://pubs.usgs.gov/sir/2025/5099/sir20255099.XML"}],"country":"United States","state":"Iowa, Missouri","otherGeospatial":"Lower Grand River","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -95.5,\n 41.5\n ],\n [\n -95.5,\n 38.5\n ],\n [\n -91.5,\n 38.5\n ],\n [\n -91.5,\n 41.5\n ],\n [\n -95.5,\n 41.5\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","contact":"Director, Central Midwest Water Science Center
U.S. Geological Survey
405 North Goodwin
Urbana, IL 61801
The U.S. Geological Survey, in cooperation with the Missouri Department of Natural Resources, estimated total nitrogen and total phosphorus concentrations at three local and five regional monitoring sites in Missouri. Temporal changes in total nitrogen and total phosphorus were quantified to evaluate whether instream nutrient concentrations have changed at local or regional scales. At the local scale sites, total phosphorus concentrations substantially increased at one site, which indicated a possible increase in phosphorus sources in the Lower Grand River hydrologic unit, while total nitrogen concentrations did not change substantially. At the regional site, annual total nitrogen and total phosphorus concentrations generally decreased. The regional decline in stream nutrients paired with the lack of nutrient reduction at the local sites indicated that nutrient reductions in the Grand River may have been driven by regional changes in nutrient export, instead of or in addition to conservation practices implemented as part of the Mississippi River Basin Healthy Watersheds Initiative.
","publicationDate":"2025-11-26","publicationStatus":"PW","contributors":{"authors":[{"text":"Kamrath, Brock J.W. 0000-0001-7118-0537","orcid":"https://orcid.org/0000-0001-7118-0537","contributorId":347859,"corporation":false,"usgs":true,"family":"Kamrath","given":"Brock","middleInitial":"J.W.","affiliations":[{"id":36532,"text":"Central Midwest Water Science Center","active":true,"usgs":true}],"preferred":true,"id":950957,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Lauderback, Courtney N. 0000-0002-6975-0331","orcid":"https://orcid.org/0000-0002-6975-0331","contributorId":363041,"corporation":false,"usgs":true,"family":"Lauderback","given":"Courtney","middleInitial":"N.","affiliations":[{"id":36532,"text":"Central Midwest Water Science Center","active":true,"usgs":true}],"preferred":true,"id":950958,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Murphy, Jennifer C. 0000-0002-0881-0919 jmurphy@usgs.gov","orcid":"https://orcid.org/0000-0002-0881-0919","contributorId":4281,"corporation":false,"usgs":true,"family":"Murphy","given":"Jennifer","email":"jmurphy@usgs.gov","middleInitial":"C.","affiliations":[{"id":36532,"text":"Central Midwest Water Science Center","active":true,"usgs":true}],"preferred":true,"id":950959,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70272103,"text":"sir20255062 - 2025 - An evaluation of the effects of different deicing salt application rates on three watersheds in Essex County, New York","interactions":[],"lastModifiedDate":"2026-02-03T16:38:12.480343","indexId":"sir20255062","displayToPublicDate":"2025-11-25T15:50:00","publicationYear":"2025","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":334,"text":"Scientific Investigations Report","code":"SIR","onlineIssn":"2328-0328","printIssn":"2328-031X","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"2025-5062","displayTitle":"An Evaluation of the Effects of Different Deicing Salt Application Rates on Three Watersheds in Essex County, New York","title":"An evaluation of the effects of different deicing salt application rates on three watersheds in Essex County, New York","docAbstract":"The U.S. Geological Survey, in cooperation with the New York State Department of Transportation, evaluated the effects of different deicing salt application rates on surface water, groundwater, and highway runoff quality near State highways in northern New York. Three reaches of State highways were tested with different deicing treatments between October 2019 and November 2022: a salt-sand mixture (Treatment A), a salt mixture applied at a lower rate (Treatment B), and a control mixture consistent with typical deicing salt amounts and application rates. Data on pavement conditions and the quality of surface water, highway runoff, and groundwater were collected. Surface electromagnetic data were also collected. Surface-water and groundwater quality downgradient from the State highways were compared with water quality at upgradient locations. The percentage of snow or ice coverage was used to evaluate the effectiveness of the salt applications.
This report provides an overview of the transport of deicing salt. The Treatment B watershed had deicing mixture applied more frequently than other highway reaches, which caused it to have the highest annual total chloride application. Despite differences in chloride application, flow-weighted mean chloride concentrations in highway runoff were comparable across treatments. Chloride concentrations were elevated in surface water and groundwater downgradient from highways relative to chloride concentrations upgradient from highways. A chloride mass balance, calculated for one treatment watershed, indicated that groundwater affected by legacy deicing practices may be contributing additional chloride to surface water. Spatial patterns from electromagnetic surveys show a shallow saline plume alongside the highway in that area.
Differences in winter severity and pavement-surface conditions drove deicing salt applications in the treatment areas. This study found that several factors affect chloride loads in the watersheds, including variable winter conditions, adaptive snow and ice management, legacy management practices, and area-specific aquifer and groundwater conditions.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20255062","collaboration":"Prepared in cooperation with the New York State Department of Transportation","usgsCitation":"Gutchess, K., Scavotto, N., Dondero, A., Woda, J., Terry, N., Smith, K., and Williams, J., 2025, An evaluation of the effects of different deicing salt application rates on three watersheds in Essex County, New York: U.S. Geological Survey Scientific Investigations Report 2025–5062, 31 p., https://doi.org/10.3133/sir20255062.","productDescription":"Report: viii, 31 p.; 2 Data Releases","numberOfPages":"31","onlineOnly":"Y","additionalOnlineFiles":"N","ipdsId":"IP-160931","costCenters":[{"id":474,"text":"New York Water Science Center","active":true,"usgs":true}],"links":[{"id":497798,"rank":8,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_118989.htm"},{"id":496533,"rank":7,"type":{"id":30,"text":"Data 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New York Water Science Center
U.S. Geological Survey
425 Jordan Road
Troy, NY 1280–8349
Managed aquifer recharge is a widespread practice for storing water in the subsurface as groundwater. At a managed aquifer recharge facility in southern Arizona, groundwater-level and repeat microgravity data were collected to monitor aquifer response. These data were used to inform parameter identification for an unsaturated-zone flow model used to simulate the recharge process. The facility, the Southeast Houghton Artificial Recharge Project (SHARP), consists of 3 surface basins (about 27,600 square meters [6.8 acres] total surface area) where recycled water is distributed in recharge cycles lasting several months, with dry periods in between. During the study period, December 2020–December 2022, Tucson Water (the City of Tucson’s water utility) reported 6.56×106 cubic meters of water (5,320 acre-feet) recharged.
Monitoring included groundwater-level observations at 3 monitoring wells and repeat microgravity measurements at as many as 22 locations (some stations were destroyed between surveys). Six gravity surveys were carried out using absolute- and relative-gravity meters. Large gravity increases, more than 250 microgals, were observed during the first repeat survey, 3.5 months after the start of recharge, but only in the immediate vicinity of the recharge basins. Data show that water moved downward to the water table, and storage changes in the unsaturated zone away from the facility were likely minimal. Gravity decreased at stations more than 1 kilometer from the facility, consistent with regional groundwater-level changes. Groundwater-level increases in wells adjacent to the recharge basins began 2 months after the second repeat gravity survey, and 5.5 months after recharge began.
Unsaturated-zone flow modeling was carried out using software that simulates water movement and parameter estimation. Model calibration was carried out by minimizing an objective function calculated from the differences between simulated and observed groundwater levels, and between simulated and observed repeat microgravity data. Including repeat microgravity data in the objective function reduced the uncertainty in estimated parameter values for saturated hydraulic conductivity and saturated water content. Modeling indicated that the unsaturated zone between the recharge basins and the water table does not become saturated even after 685 days of simulated infiltration. This gradual wetting may account for increasing infiltration rates over time, as hydraulic conductivity increases with increasing water content. Unsaturated-zone water content decreased rapidly between recharge cycles. Model-simulated groundwater mounding extended about 1 kilometer from the center of SHARP after the 685-day period following the onset of recharge.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20255017","collaboration":"Prepared in cooperation with Tucson Water","programNote":"Water Availability and Use Program","usgsCitation":"Wildermuth, L.M., Kennedy, J.R., and Conrad, J.L., 2025, Groundwater response to managed aquifer recharge at the Southeast Houghton Artificial Recharge Project in Tucson, Arizona: U.S. Geological Survey Scientific Investigations\nReport 2025–5017, 38 p., https://doi.org/10.3133/sir20255017.","productDescription":"Report: v, 38 p.; Data Release","numberOfPages":"38","onlineOnly":"Y","ipdsId":"IP-152298","costCenters":[{"id":128,"text":"Arizona Water Science Center","active":true,"usgs":true}],"links":[{"id":497795,"rank":7,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_118986.htm"},{"id":495375,"rank":6,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/P9E19SSK","text":"USGS data release","description":"Landrum, M.T., 2021, Repeat microgravity data from South Houghton Area Recharge Project, Tucson, Arizona, 2020-2022 (ver. 2.0, August 2024): U.S. Geological Survey data release, https://doi.org/10.5066/P9E19SSK.","linkHelpText":"Repeat microgravity data from South Houghton Area Recharge Project, Tucson, Arizona, 2020-2022 (ver. 2.0, August 2024)"},{"id":495371,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/sir/2025/5017/sir20255017.pdf","text":"Report","size":"35 MB","linkFileType":{"id":1,"text":"pdf"},"description":"SIR 2025-5017 PDF"},{"id":495370,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/sir/2025/5017/coverthb.jpg"},{"id":495372,"rank":3,"type":{"id":39,"text":"HTML Document"},"url":"https://pubs.usgs.gov/publication/sir20255017/full","linkFileType":{"id":5,"text":"html"},"description":"SIR 2025-5017 HTML"},{"id":495374,"rank":5,"type":{"id":34,"text":"Image Folder"},"url":"https://pubs.usgs.gov/sir/2025/5017/images"},{"id":495373,"rank":4,"type":{"id":31,"text":"Publication XML"},"url":"https://pubs.usgs.gov/sir/2025/5017/sir20255017.XML","description":"SIR 2025-5017 XML"}],"country":"United States","state":"Arizona","city":"Tucson","otherGeospatial":"Southeast Houghton Artificial Recharge Project","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -110.758333,\n 32.159722\n ],\n [\n -110.758333,\n 32.141667\n ],\n [\n -110.791667,\n 32.141667\n ],\n [\n -110.791667,\n 32.159722\n ],\n [\n -110.758333,\n 32.159722\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","contact":"Director,
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U.S. Geological Survey
520 N. Park Avenue
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The U.S. Geological Survey has developed a high-resolution inset groundwater-flow model in the Mississippi Delta as part of an interdisciplinary collaboration coordinated by the Mississippi Alluvial Plain project to provide a tool that stakeholders can use to support water-resource management decisions. Groundwater withdrawals from the Mississippi River Valley alluvial (MRVA) aquifer have been vital to support agricultural production in the region, but substantial groundwater-level declines near Shellmound, Mississippi, have caused concerns for long-term sustainability of the aquifer. To better understand the subsurface and try to mitigate the long-term groundwater-level declines, stakeholders have undertaken actions including a Groundwater Transfer and Injection Pilot (GTIP) project using a riverbank filtration-based managed aquifer recharge approach. The pilot project consisted of extracting groundwater near the Tallahatchie River and reinjecting it into the aquifer 3 kilometers west where water levels have substantially declined. A high-resolution airborne electromagnetic (AEM) survey was also completed to collect electrical resistivity data to support the GTIP project and the development of the groundwater model.
The inset groundwater-flow model was developed to (1) integrate the AEM data into the optimal layering configuration of the MRVA aquifer that the available observation data can support through calibration, and (2) assess the potential effect of the GTIP project on the groundwater levels. The AEM data were processed into three different layering configurations leading to the development of model A (18 layers), model B (16 layers), and model C (8 layers), all at a 100- x 100-meter cell spatial resolution using the U.S. Geological Survey modular finite-difference flow model 6 code with Newton-Raphson formulation. The model development process integrated recent advances in modeling, such as the incorporation of AEM data, the use of outputs from the soil-water-balance (SWB) model, and the Aquaculture and Irrigation Water-Use Model, and was facilitated by robust automation using the open-source python packages Modflow-setup and SFRmaker. Using Parameter Estimation ++ Iterative Ensemble Smoother, the three numerical groundwater-flow models (models A, B, and C) were calibrated against a set of observations, which included aquifer groundwater levels, streamflows, stream stage, and aquifer transmissivity. Results indicate that the detailed representation of MRVA aquifer layers in model A produced the best calibrated model by history matching, and the integration of data representing surficial connectivity played a key role in improving groundwater recharge and enhancing the ability of the model to match groundwater levels in the cone of depression. A forecast model simulated the managed aquifer recharge approach, and the results indicated that, given average irrigation and recharge conditions (2010–15), the GTIP project has the potential to induce groundwater-level increases of as much as 3 meters around the injection site, but a sustained increase would require repetition in subsequent years of water transfer at 2022 rates or above.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20255055","collaboration":"Prepared in cooperation with U.S. Department of Agriculture Agricultural Research Service and the Mississippi Department of Environmental Quality","programNote":"Water Availability and Use Science Program","usgsCitation":"Guira, M., Traylor, J.P., Leaf, A.T., and Weisser, A.R., 2025, An inset groundwater-flow model to evaluate the effects of layering configuration on model calibration and assess managed aquifer recharge near Shellmound, Mississippi: U.S. Geological Survey Scientific Investigations Report 2025–5055, 134 p., https://doi.org/10.3133/sir20255055.","productDescription":"Report: ix, 134 p.; 3 Figures: 11.00 x 8.50 inches; Data Release; Dataset","numberOfPages":"148","onlineOnly":"Y","additionalOnlineFiles":"N","ipdsId":"IP-154357","costCenters":[{"id":464,"text":"Nebraska Water Science Center","active":true,"usgs":true},{"id":37947,"text":"Upper Midwest Water Science Center","active":true,"usgs":true},{"id":84311,"text":"Central Plains Water Science Center","active":true,"usgs":true}],"links":[{"id":497793,"rank":9,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_118974.htm"},{"id":495719,"rank":8,"type":{"id":29,"text":"Figure"},"url":"https://pubs.usgs.gov/sir/2025/5055/downloads/","text":"Layered figures","linkFileType":{"id":1,"text":"pdf"},"linkHelpText":"Downloadable layered PDF files for figures 11, 12, and 13"},{"id":495626,"rank":6,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/P13DWA86","text":"USGS data release","linkHelpText":"Inset models used to evaluate the effects of layering configuration on model calibration from 1900 to 2018, and assess managed aquifer recharge near Shellmound, Mississippi, from 2019 to 2050"},{"id":495670,"rank":7,"type":{"id":39,"text":"HTML Document"},"url":"https://pubs.usgs.gov/publication/sir20255055/full"},{"id":495623,"rank":3,"type":{"id":31,"text":"Publication XML"},"url":"https://pubs.usgs.gov/sir/2025/5055/sir20255055.XML"},{"id":495622,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/sir/2025/5055/sir20255055.pdf","text":"Report","size":"40 MB","linkFileType":{"id":1,"text":"pdf"},"description":"SIR 2025-5055"},{"id":495625,"rank":5,"type":{"id":28,"text":"Dataset"},"url":"https://doi.org/10.5066/F7P55KJN","text":"USGS National Water Information System database","linkHelpText":"- USGS water data for the Nation"},{"id":495624,"rank":4,"type":{"id":34,"text":"Image Folder"},"url":"https://pubs.usgs.gov/sir/2025/5055/images/"},{"id":495621,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/sir/2025/5055/coverthb.jpg"}],"country":"United States","state":"Mississippi","city":"Shellmound","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -90.55,\n 33.8\n ],\n [\n -90.55,\n 33.5\n ],\n [\n -90.1667,\n 33.5\n ],\n [\n -90.1667,\n 33.8\n ],\n [\n -90.55,\n 33.8\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","contact":"Director, Nebraska Water Science Center
U.S. Geological Survey
5231 South 19th Street
Lincoln, NE 68512