Report of the River Master of the Delaware River for the Period December 1, 2013–November 30, 2014
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Acknowledgments
The Office of the Delaware River Master’s (ODRM) daily operation records were prepared from hydrologic data collected daily. Data for these records were collected and computed by the ODRM or provided by the following agencies and utilities. Data for streamflow of the Delaware River at Montague, New Jersey, and other locations and tributaries in this report were provided by the U.S. Geological Survey (USGS); for the Pepacton, Cannonsville, and Neversink Reservoirs by the New York City Department of Environmental Protection (NYCDEP); for Lake Wallenpaupack by the PPL Corporation; and for Rio Reservoir by Eagle Creek Renewable Energy, LLC. Quantitative precipitation forecasts and some precipitation data were provided by the National Weather Service offices, the NYCDEP, and the ODRM. Marie Owens and Margaret Philips of the USGS assisted with and contributed to this report by collecting, organizing, and reviewing data.
River Master Letter of Transmittal and Special Report
Office of the Delaware River Master
U.S. Geological Survey
415 National Center
Reston, VA 20192
January 3, 2024
The Honorable
John G. Roberts, Jr.
Chief Justice of the United States
The Honorable
John Carney
Governor of Delaware
The Honorable
Phil Murphy
Governor of New Jersey
The Honorable
Kathy Hochul
Governor of New York
The Honorable
Josh Shapiro
Governor of Pennsylvania
The Honorable
Eric Adams
Mayor of the City of New York
No. 5, Original—October Term, 1950
State of New Jersey, Complainant,
v.
State of New York and City of New York, Defendants,
Commonwealth of Pennsylvania and State of Delaware, Intervenors.
To the Chief Justice of the United States:
For the record, and in compliance with the provisions of the Amended Decree of the Supreme Court of the United States entered June 7, 1954, I hereby transmit the 61st Annual Report of the River Master of the Delaware River for the 12-month period from December 1, 2013, to November 30, 2014. In this report, this period is referred to as the River Master “report year.”
During the 2014 report year, monthly precipitation in the upper Delaware River Basin ranged from 33 percent of the long-term average in September 2014 to 137 percent of the long-term average in October 2014. Precipitation from December to May, when reservoirs typically refill, was 20.16 inches. Precipitation was below normal in January, March, April, August, September, and November, and above normal in the other 6 months.
When the report year began on December 1, 2013, combined useable storage in the New York City reservoirs in the upper Delaware River Basin was 200.133 billion gallons or 73.9 percent of combined storage capacity. The combined usable storage was 154.547 billion gallons at the end of the report year on November 30, 2014. During the report year, operations in the basin were conducted as stipulated by the Decree and the Flexible Flow Management Program (FFMP).
On January 23, 2014, the Delaware River Master Advisory Committee (Advisory Committee) met at the Delaware River Basin Commission (DRBC) offices in West Trenton, New Jersey, to discuss the status and structure of the next FFMP agreement. During the report year, the following individuals served as members of the Advisory Committee:
Advisory Committee
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Delaware—David Wunsch
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New Jersey—Michele Siekerka
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New York—Mark Klotz
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New York City—Paul Rush
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Pennsylvania—Kelly Heffner
During the report year, the River Master and staff participated in many water-supply-related meetings of the DRBC. The Deputy Delaware River Master met periodically with representatives of the Decree Parties as a member of the Decree Parties Work Group and the DRBC’s Regulated Flow Advisory Committee. In addition to management of reservoir releases and streamflow in the upper Delaware River Basin, an issue of particular interest to the River Master was the impending expiration of the current FFMP on June 1, 2014.
River Master operations were executed through the U.S. Geological Survey (USGS) Office of the Delaware River Master (ODRM) at Milford, Pennsylvania. Marie Hynes, Deputy Delaware River Master, remained in charge of the office, assisted by hydrologists Arthur Lilienthal and Gary N. Paulachok.
During the report year, the ODRM continued the weekly distribution of a summary hydrologic report. These reports contain provisional data on precipitation in the upper Delaware River Basin, releases and spills from New York City reservoirs to the Delaware River, diversions to the New York City water-supply system, reservoir contents, the daily segregation of flow of the Delaware River at the USGS streamgage at Montague, New Jersey (USGS site number 01438500), and diversions by the State of New Jersey. The reports were distributed to members of the Advisory Committee and other parties interested in Delaware River operations. A monthly summary of hydrologic conditions was also provided to Advisory Committee members. The weekly and monthly hydrologic reports are available through the ODRM website (https://webapps.usgs.gov/odrm/data/data.html).
This report documents Delaware River operations during the report year. During the year, New York City diverted 198.447 billion gallons from the Delaware River Basin and released 170.037 billion gallons from Pepacton, Cannonsville, and Neversink Reservoirs to the Delaware River for conservation purposes. A total of 33.159 billion gallons was spilled from the Pepacton, Cannonsville, and Neversink Reservoirs. The River Master directed releases from these reservoirs to the Delaware River that totaled 51.889 billion gallons. This report also describes water quality at various monitoring sites on the Delaware River estuary and includes basic data on the chemical properties and physical characteristics of the water and presents summary statistics.
Throughout the year, diversions to New York City’s water-supply system and releases designed to maintain the flow of the Delaware River at Montague were made as directed by the ODRM. Diversions by New York City from its reservoirs in the Delaware River Basin did not exceed the limit stipulated by the Decree. Diversions by the State of New Jersey were also within stipulated limits.
The River Master and staff are grateful for the continued cooperation and support of the Decree Parties. Also, the contributions of the PPL Corporation and Eagle Creek Renewable Energy, LLC, in informing the ODRM of plans for power generation and providing data on reservoir releases and elevations are greatly appreciated.
Sincerely yours,
/Signed/
Kendra Russell, P. E.
Delaware River Master
Executive Summary
A Decree of the Supreme Court of the United States, entered June 7, 1954 (New Jersey v. New York, 347 U.S. 995), established the position of Delaware River Master within the U.S. Geological Survey. In addition, the Decree authorizes the diversion of water from the Delaware River Basin and requires compensating releases from specific reservoirs owned by New York City to be made under the supervision and direction of the River Master. The Decree stipulates that the River Master provide reports to the Court, not less frequently than annually. This report is the 61st annual report of the River Master of the Delaware River. The report covers the 2014 River Master report year, which is the period from December 1, 2013, to November 30, 2014.
During the report year, precipitation in the upper Delaware River Basin was 42.40 inches or 95 percent of the long-term average. On December 1, 2013, combined useable storage in New York’s Pepacton, Cannonsville, and Neversink Reservoirs in the upper Delaware River Basin was 200.133 billion gallons or 73.9 percent of the combined capacity of 270.8 billion gallons. The reservoirs were at about 99.7 percent of usable capacity on May 31, 2014. Combined storage in the Pepacton, Cannonsville, and Neversink Reservoirs decreased below 80 percent of combined capacity in late August. The lowest combined storage was 151.730 billion gallons or 56 percent of combined capacity on November 24, 2014. Delaware River Master operations during the year were conducted as stipulated by the Decree and the Flexible Flow Management Program.
Diversions from the Delaware River Basin by New York City and the State of New Jersey fully complied with the Decree. Reservoir releases were made as directed by the River Master at rates designed to meet the flow objective for the Delaware River at Montague, New Jersey, on 94 days during the report year. Interim Excess Release Quantity and conservation releases, designed to relieve thermal stress and protect the fishery and aquatic habitat in the tailwaters of the reservoirs, were also made during the report year.
Water quality in the Delaware River estuary between streamgages at Trenton, New Jersey, and Reedy Island Jetty, Delaware, was monitored at several locations. Data on water temperature, specific conductance, dissolved oxygen, and pH were collected continuously by electronic instruments at four locations.
Introduction
An amended Decree of the Supreme Court of the United States, entered June 7, 1954 (New Jersey v. New York, 347 U.S. 995), which superseded a 1931 Decree, authorizes the diversion of water from the Delaware River Basin and provides for releases of water from three New York City reservoirs—Pepacton, Cannonsville, and Neversink—to the upper Delaware River (https://webapps.usgs.gov/odrm/about/decree). The Decree stipulates that these diversions and releases be made under the supervision and direction of the Office of the Delaware River Master (ODRM). The Decree also stipulates that reports on Delaware River operations be made to the Court no less frequently than annually. The reports can be accessed at https://webapps.usgs.gov/odrm/publications/publications.
This report documents operations from December 1, 2013, to November 30, 2014, or the 2014 River Master report year, hereafter referred to as the “report year.” This report also presents information on water quality in the Delaware River estuary during the report year.
Since 2007, the Decree Parties (Delaware, New Jersey, New York, New York City, and Pennsylvania) have unanimously approved a series of Flexible Flow Management Program (FFMP) agreements (available at https://webapps.usgs.gov/odrm/ffmp/flexible-flow-management-program) to manage the shared waters of the Delaware River Basin. On December 10, 2008, the Decree Parties signed an FFMP to guide the operations of the ODRM (Russell and others, 2019). The Agreement was in effect until May 31, 2011.
A 1-year FFMP Agreement that became effective on June 1, 2014 (appendix 1; also available at https://webapps.usgs.gov/odrm/documents/ffmp/FFMP_2014_Agreement.pdf), is an extension of the June 1, 2011, Agreement (DiFrenna and others, 2020) and incorporates the changes of the 2012 and 2013 Agreements. The June 1, 2011, Agreement changed the term Conditional Storage Objective (CSO) to Conditional Seasonal Storage Objective (CSSO).
Some hydrologic data presented in this report are streamflow and water quality records for U.S. Geological Survey (USGS) data-collection sites. The USGS collected and computed these records in cooperation with the States of New York and New Jersey, the Commonwealth of Pennsylvania, and the City of New York. The locations of major streams and reservoirs, and selected USGS streamgages in the Delaware River Basin, are shown in figure 1.
Map showing the Delaware River Basin upstream from Wilmington, Delaware. The Delaware River Basin boundary is shown along with key and index gaging stations; refer to the “Glossary” section for definitions.
Method to Determine Directed Releases From New York City Reservoirs
The data and computations of the streamflow components form the operational record used by the ODRM to carry out specific responsibilities related to the “Montague flow objective” (appendix 1). The operational record has two parts: (1) segregating the streamflow components of the current daily mean discharge at the USGS streamgage at Montague, New Jersey (N.J.) (USGS site number 01438500), to compute the uncontrolled runoff and (2) forecasting the uncontrolled runoff and using forecasted information from other sources to predict the flow at the Montague site with adequate advance time to direct releases. The forecasting process is used to determine whether the ODRM directs New York City reservoirs to release water to maintain the minimum Montague flow objective at the Montague site, which is defined in table 1 of appendix 1.
Segregating Streamflow Components—Delaware River at Montague, New Jersey
The segregation of streamflow at the Montague site involves determining the components of flow, including releases from New York City reservoirs, releases from Lake Wallenpaupack in Pennsylvania and Rio Reservoir in New York for generation of hydroelectric power, and uncontrolled runoff. For the segregation of components of daily mean flow at the Montague site, the following data are used:
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1. controlled releases from the Pepacton, Cannonsville, and Neversink Reservoirs of New York City;
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2. controlled releases from Lake Wallenpaupack on Wallenpaupack Creek to produce hydroelectric power; and
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3. controlled releases from the Rio Reservoir on the Mongaup River to produce hydroelectric power.
To determine the contributions of each of these releases, the amount of time for water to travel from the release point to the Montague site is required. The various traveltimes are used to determine the appropriate time-delayed flow contributions from the above sources. The time-adjusted controlled flows of the sources are subtracted from the total streamflow measured at the Montague site to determine the uncontrolled runoff (including reservoir spills and groundwater) from the drainage area upstream from the Montague site.
Traveltimes were computed from reservoir- and powerplant-operations data and historical streamflow records. The traveltimes are generally adequate for ODRM operations. Occasionally, however, significant exceptions are observed. For example, during a large increase in a directed release from Cannonsville Reservoir, the arrival time of the water at the Montague site can be delayed as long as 1.5 days because a substantial amount of water must first fill the channel before a steady flow arrives at the Montague site. During winter, ice formation and lower streamflow gradually increase the resistance to water flow, resulting in increased traveltimes. No adjustments were made to compensate for increased traveltimes during these periods of the report year. The following list gives the average times for the effective travel of water from the various sources of controlled supply to the Montague site. These traveltimes, in hours, were used for flow routing during the 2014 report year: Pepacton Reservoir, 60; Cannonsville Reservoir, 48; Neversink Reservoir, 33; Lake Wallenpaupack, 16; and Rio Reservoir, 8.
Forecasting Streamflow—Delaware River at Montague, New Jersey
The releases from New York City’s reservoirs necessary to meet the Montague flow objective were computed based on the forecasted streamflow at the Montague site, exclusive of releases from New York City’s Delaware River Basin reservoirs. The flow must be forecast 3 days in advance to account for the longest traveltime needed for the flow to reach the Montague site from the Pepacton Reservoir.
The electric utilities PPL Corporation and Eagle Creek Renewable Energy, LLC, provided daily forecasts of power generation and releases to the Delaware River from Lake Wallenpaupack and Rio Reservoir, respectively, to the ODRM. Because the hydroelectric plants were used mainly for meeting rapidly varying peak-power demands, the forecasts were subject to various modifying factors, including the vagaries of weather on electricity demand. In addition, because the power companies are members of regional transmission organizations, the demand for power outside the local service area can unexpectedly affect generation schedules. Consequently, at times, the actual use of water for power generation differs considerably from the forecasts used in the design of reservoir releases.
For computational purposes during periods of low flow, estimates of uncontrolled runoff at the Montague site were treated as two components: (1) current runoff and (2) forecasted runoff from precipitation.
An estimate of uncontrolled runoff was computed by using a recession procedure. A recession curve of uncontrolled inputs was developed using the flow at the Montague streamgage and is used to forecast the uncontrolled portion of flow at the Montague site 3 days in advance. Forecasted runoff was determined from data provided by the National Weather Service office in Binghamton, New York (N.Y.), which provided quantitative forecasts of average precipitation and air temperatures for the 3,480-square-mile (mi2) drainage basin upstream from Montague, N.J. During winter, runoff was estimated based on the status of snow and ice, along with forecasted precipitation and temperature. During other periods, forecasted precipitation was used to estimate runoff.
The forecasted flow at the Montague site, exclusive of releases from New York City’s Delaware River Basin reservoirs, is computed as the sum of forecasted releases from hydroelectric power reservoirs, estimated uncontrolled runoff—including conservation releases from Rio Reservoir—and estimated runoff from predicted rainfall. Each of these inputs is adjusted for traveltime. If the computed total flow is less than the flow objective at the Montague site, the deficiency is made up by releases from New York City’s reservoirs, as directed by the ODRM.
Based on the previous day’s provisional data, a balancing adjustment is applied to the following day’s release design. The balancing adjustment is computed as 10 percent of the difference between the cumulative directed release and the cumulative directed release required for exact forecasting and is limited to a maximum of 50 cubic feet per second (ft3/s) magnitude. The balancing adjustment calls for more water to be released when previous directed releases (or a lack of releases) were insufficient to meet the Montague flow objective. The adjustment calls for less water to be released when previous directed releases were higher than required to meet the Montague flow objective.
When updated forecasts of precipitation or powerplant releases showed appreciable changes after a release was directed, the release required from New York City’s reservoirs was recomputed based on the updated forecasts. Commonly, this procedure resulted in a reduced release requirement for New York City reservoirs that day. Only final values for releases from New York City reservoirs are presented in this report.
Hydrologic Conditions
Precipitation
Average precipitation in the Delaware River Basin above Montague, N.J., totaled 42.40 inches (in.) during the 2014 report year, which is 95 percent of the 73-year long-term average (table 1, in back of report). Monthly precipitation ranged from 33 percent of the long-term average in September 2014 to 143 percent of the long-term average in February 2014 (table 1). Precipitation data for the 2014 report year are computed from records for 10 geographically distributed stations operated by the National Weather Service, the New York City Department of Environmental Protection’s (NYCDEP) Bureau of Water Supply, and the ODRM.
The seasonal period from December to May is typically when surface-water and groundwater reservoirs refill. During this period in 2013–2014, total precipitation was 20.16 in., which is about 98 percent of the 73-year long-term average. During the June to November period, total precipitation was 22.24 in., which is 92.6 percent of the 73-year long-term average.
Reservoir Storage
Table 2 summarizes the “point of maximum depletion” and other pertinent levels, and the contents of the Pepacton, Cannonsville, and Neversink Reservoirs. The NYCDEP provided this data.
Table 2.
Elevation and capacities of structures of the Pepacton, Cannonsville, and Neversink Reservoirs.[ft, foot; Mgal, million gallons; NA, not available; —, not applicable]
Daily storage in the Pepacton, Cannonsville, and Neversink Reservoirs above the point of maximum depletion, or minimum full-operating level, is given in tables 3, 4, and 5 (in back of report), respectively, and combined storage during the report year is shown in figure 2. Data for these records were provided daily by the NYCDEP, and summary calculations were computed by the ODRM. On December 1, 2013, combined useable storage in the three reservoirs was 200.133 billion gallons, or 73.9 percent of the combined capacity. From December to May, inflow to the New York City reservoirs typically exceeds outflow, consequently increasing storage. Combined storage increased during the report year, and the reservoirs were at about 99.7 percent of usable capacity on May 31, 2014. Combined storage remained high (above 80 percent of combined capacity) until September 2014. The lowest combined storage was 151.730 billion gallons (56 percent) on November 24, 2014 (fig. 2).
The three reservoirs spilled a total of 33.159 billion gallons during the year when reservoirs reached maximum capacity. Pepacton Reservoir spilled during the following periods: April 15–23, 2014; May 3–28, 2014; and June 25–July 7, 2014. Cannonsville Reservoir spilled during the following periods: April 15–24, 2014, and May 6–29, 2014. Neversink Reservoir spilled during the following periods: January 13–15, 2014, and July 14–22, 2014. Combined storage reached a maximum for the report year on May 18, 2014, at 277.028 billion gallons. At the end of the report year, the combined storage was 154.547 billion gallons, or 57 percent of the combined capacity, on November 30, 2014.
Graph showing rule curves and actual contents for New York City reservoirs in the Delaware River Basin, from December 1, 2013, to November 30, 2014. Full capacity usable storage line and the five conservation release rate zones (L1–5) are shown. The conservation release rate zones are defined in the “conservation release” definition in the “Glossary” section.
Operations
Operations for December 1, 2013, through November 30, 2014, were conducted as described by the FFMP (revised, effective June 1, 2013, and June 1, 2014). The allowable diversion to New York City was 800 million gallons per day (Mgal/d) throughout the year. The Montague flow objective was 1,750 ft3/s. The allowable diversion to New Jersey was 100 Mgal/d. Conservation releases from New York City reservoirs were made at the rates shown in tables 4a–g of the June 1, 2013, FFMP (DiFrenna and others, 2022) and the June 1, 2014, FFMP (appendix 1), including tables 4f and 4g in December, tables 4e–g in January, tables 4f and 4g in February through March, tables 4d–g in April, tables 4f and 4g in May through October, and table 4g in November 2014 (see “Archived OST Summary Data” from New York City’s Operational Support Tool [OST] at https://webapps.usgs.gov/odrm/data/data.html).
Diversions to New York City Water Supply
The 1954 amended Decree authorizes New York City to divert water from the Delaware River Basin at a rate not to exceed the rolling average equivalent of 800 Mgal/d. The Decree specifies that the diversion rate shall be computed as the aggregate total diversion beginning June 1 of each year divided by the total number of days elapsed since the preceding May 31 (appendix 1).
Records of daily diversions through New York City’s East Delaware, West Delaware, and Neversink Tunnels (fig. 1) were provided to the ODRM by the NYCDEP. These records were obtained from New York City’s calibrated instruments, which are connected to Venturi meters installed in the tunnel conduits. The measured flows were transmitted electronically on a 15-second interval to New York City computers, and 5-minute interval release and diversion quantities for the preceding 5-minute period were computed using the instantaneous rate-of-flow data from each instrument. These 5-minute quantities were then summed to compute daily total flows, which were reported each day to the ODRM. Each week, the computed diversion values were checked against the flow meter totalizer readings by the NYCDEP and corrected when necessary.
Daily diversions during the report year from the Pepacton, Cannonsville, and Neversink Reservoirs to the New York City water-supply system (Rondout Reservoir, N.Y.) are given in table 6 (in back of report). A running account of the average rates of combined diversions from the three reservoirs from June 1, 2013, computed as stipulated by the Decree, is also shown in table 6. A total of 198.447 billion gallons of water was diverted to the New York City water-supply system during the report year with an average of 544 Mgal/d, which is below the maximum diversion rate. The maximum daily diversion from a single reservoir was 515 million gallons (Mgal) on November 1, 2014, from Pepacton Reservoir. The maximum daily combined diversion from all three reservoirs was 965 Mgal on March 13, 2014. Diversions by New York City did not exceed the limits stipulated by the Decree and the FFMP. Data on water consumption by New York City for each calendar year since 1950, from all sources of supply, are presented in table 7 (in back of report).
The East Delaware Tunnel is used to divert water from Pepacton Reservoir to Rondout Reservoir. The hydroelectric powerplant at the downstream end of the East Delaware Tunnel operated most days of the report year. When the powerplant was not in operation, some water leaked through the wicket gates and was not recorded on the totalizer. A current-meter measurement made in 1989 showed that the (assumed constant) rate of leakage is about 12.4 ft3/s (8.0 Mgal/d). Because the powerplant was not in operation for the equivalent of 39 days during the 2014 report year, the estimated quantity of unmeasured leakage (diverted but not recorded) was about 0.3 billion gallons.
The West Delaware Tunnel is used to divert water from Cannonsville Reservoir to Rondout Reservoir. When the valves were closed, inspections of the channel below the outlet revealed negligible leakage. A hydroelectric powerplant uses water diverted through the West Delaware Tunnel, but the powerplant only operates when diversions are less than 300 Mgal/d. When the powerplant is not operating, the valves on the pipelines to the plant are closed, and there is no leakage through the system.
The Neversink Tunnel is used to divert water from Neversink Reservoir to Rondout Reservoir. A hydroelectric powerplant uses water diverted through the Neversink Tunnel. When the powerplant is not operating and the main valve on the diversion tunnel is open, leakage develops that is not recorded by the Venturi meters. One current-meter measurement made in 1999 showed a leakage rate of 16.2 ft3/s (10.5 Mgal/d). The leakage is included in the recorded flow when the powerplant is operating. No leakage occurs when the main valve on the tunnel is closed. During the 2014 report year, the powerplant operated part of the day on most days and was not operated for the equivalent of 203 days. About 2.1 billion gallons of water was diverted but not recorded, according to the leakage rate noted above and in records of powerplant operation.
Diversions by New Jersey
The Decree authorizes the State of New Jersey to divert water from the Delaware River and its tributaries in New Jersey to areas outside of the Delaware River Basin without compensating releases. Under the FFMP, New Jersey diversions shall not exceed 100 Mgal/d as a monthly average, and the daily mean diversion shall not exceed 120 Mgal/d. When the lower part of the Delaware River Basin is in a drought warning period, diversions shall not exceed 85 Mgal/d as a running average.
The USGS streamgage on the Delaware and Raritan Canal at Port Mercer, N.J. (USGS site number 01460440; fig. 1), is the official control point for measuring these diversions by New Jersey. Based on data collected by the USGS at this site, the maximum monthly mean diversion was 99.1 Mgal/d during February 2014 (table 8, in back of report). The maximum daily mean diversion was 109 Mgal/d on February 17 and 18, 2014 (table 8). Diversions by New Jersey did not exceed the limits stipulated by the FFMP.
Montague Flow Objective
The components of forecasted flow at the Montague site during low flow (forecasted releases from power reservoirs, estimated uncontrolled runoff including conservation releases from Rio Reservoir, and forecasted increases in runoff from precipitation) and the sums of flows exclusive of releases from New York City’s reservoirs are given in table 9 (in back of report). If the computed sum of the components is less than the Montague flow objective, then the deficiency is made up by releases from New York City’s reservoirs, as directed by the ODRM. Table 10 (in back of report) presents the ODRM daily operations record of reservoir releases and segregation of the various components contributing to the flow of the Delaware River, as measured at the Montague site.
Based on provisional data and exclusive of water released from the New York City reservoirs, the forecasted flow of the Delaware River at the Montague site was greater than the flow objective on all days from December 1, 2013, to August 4, 2014. Releases of 51.889 billion gallons were ordered over 94 days for August through November. The observed daily mean discharge at the Montague site was greater than the applicable flow objective (1,750 ft3/s) on all but 19 days during this period (table 11, in back of report).
The forecasted flow at the Montague site, exclusive of water released from the New York City reservoirs, was less than the flow objective on 94 days between August 8, 2014, and November 27, 2014, and directed releases were required (table 9). On 19 days between August 18, 2014, and November 26, 2014, the observed flow was less than or equal to the flow objective (table 10). However, 13 observed flows were within 10 percent of the flow objective. On October 6, 2014, the observed flow was 1,430 ft3/s, which is 82 percent of the flow objective (table 11).
The components of the total observed flow at the Montague site for August through November 2014 are shown in figure 3. The flow is segregated into the portion derived from the New York City reservoirs, the portion contributed by the power reservoirs, and the uncontrolled runoff from the drainage area below the reservoirs. As described above, the uncontrolled runoff was computed as the residual of observed flow minus releases and was subject to errors in the observations, transit times, and routings of the various flow components. The conservation release from the Rio Reservoir is included in the uncontrolled runoff component. The effect of these uncertainties is incorporated into the computation of uncontrolled runoff.
Graph showing components of flow, Delaware River at Montague, New Jersey (U.S. Geological Survey site number 01460440), from August 8 to November 30, 2014. Discharge, in cubic feet per second, is shown for New York City reservoirs, powerplant reservoirs, and uncontrolled runoff. The Montague flow objective is represented as a dashed line.
Excess Release Quantity and Interim Excess Release Quantity
Per section 4c of the 2014 FFMP (appendix 1), the Excess Release Quantity is used in support of the Interim Excess Release Quantity (IERQ). The IERQ is 10.0 billion gallons (15,468 cubic feet per second for a day [(ft3/s)-d]). In 2014, 3.91 billion gallons (6,045 [ft3/s]-d) of the IERQ was incorporated into the release tables to enhance base releases from the New York City Delaware River Basin reservoirs. The IERQ balance of 6.09 billion gallons (9,423 [ft3/s]-d) is reserved and may be used for additional releases to meet the Trenton flow objective or to establish an Extraordinary Needs Bank as described in section 4d of the 2014 FFMP (appendix 1). Per section 4c of the 2014 FFMP, upon request by the “Lower Basin States” or the Delaware River Basin Commission (DRBC), New York City is required to release water in sufficient quantities from the remaining IERQ balance to maintain a flow in the Delaware River at Trenton, N.J. (USGS site number 01463500), of 3,000 ft3/s during basinwide normal conditions from June 15 to March 15 (known as the seasonal period). The maximum amount of water required to be released from the remaining IERQ in any seasonal period is 70 billion gallons. New York City is required to make releases from the IERQ until May 31, 2015, or until the aggregate quantity of the IERQ is exhausted, whichever occurs first.
As described in section 4d of the 2014 FFMP (appendix 1), the Decree Parties, the DRBC, and the ODRM may at any time review extraordinary water needs to support such research, aquatic life, or other water-use activity as may be approved by the DRBC. Upon unanimous agreement, the Decree Parties may bank all or a portion of the IERQ remaining in an IERQ Extraordinary Needs Bank to provide for such extraordinary water needs. Banked quantities are deducted from the IERQ, and any unused Extraordinary Needs Bank water is returned to the IERQ. In 2014, 3.129 billion gallons of IERQ water was released from September through November to maintain flows at Trenton, N.J.
Tailwaters Habitat Protection and Discharge Mitigation Program
The FFMP established a Tailwaters Habitat Protection and Discharge Mitigation Program, which consists of (1) conservation releases designed for protection of the ecology in the tailwaters below the New York City reservoirs and (2) discharge mitigation releases designed to help mitigate the effects of water spilling from the full Delaware River Basin reservoirs. Controlled releases were made from the New York City Delaware River Basin reservoirs in accordance with the FFMP. From December 1, 2013, to November 30, 2014, 170.037 billion gallons was released from the New York City Delaware River Basin reservoirs in accordance with the Tailwaters Habitat Protection and Discharge Mitigation Program.
Comparison of Delaware River Master Operations Data With Other Records
The ODRM operations are conducted on a daily basis and, by necessity, use preliminary streamflow data. This section compares the records used in ODRM operations with the final data published for selected USGS streamgages. Release data were reported in million gallons per day and converted to cubic feet per second for comparisons.
Analysis of Forecasts
Based on anticipated contributions from the components described previously but excluding releases from New York City reservoirs, forecasted streamflow at the Montague site differed from the observed flow on most days. Occasionally, variations in the components were partially compensating, and observed flows compared favorably with forecasted flows.
The forecasted flow of the Delaware River at the Montague site, exclusive of releases from the New York City reservoirs, was less than the Montague flow objective on most days for August 5 through October 15, 2014, and for October 28 through November 27, 2014, as indicated by directed releases on 94 days during the report year. Table 12 computes forecasted and actual hydroelectric power releases and uncontrolled runoff from August 1 to November 30, 2014.
Table 12.
Cumulative forecasted and actual release volume from Lake Wallenpaupack and Rio Reservoir, and uncontrolled runoff from July 1 to November 1, 2014.[(ft3/s)-d, cubic foot per second for a day]
For August 1 through November 30, 2014, as shown in table 12, actual releases from Lake Wallenpaupack and Rio Reservoir averaged 0.6 and 111 percent more than the forecasted releases, respectively. Powerplant forecasted volumes are calculated from columns 1 and 2 in table 9; powerplant actual releases are calculated from columns 5 and 6 in table 10. The observed runoff (column 10 in table 10) from the uncontrolled area was about 6.0 percent more than the forecasted runoff (columns 3 + 4 in table 9).
On any given day, forecasted and actual releases from Lake Wallenpaupack and Rio Reservoir can differ considerably. The differences between actual and forecasted daily releases from August 1 to November 30, 2014, are as follows: daily releases at Lake Wallenpaupack varied between 206 (ft3/s)-d less than forecasted releases and 442 (ft3/s)-d greater than forecasted releases, and daily releases at Rio Reservoir differed by 301 (ft3/s)-d less than forecasted releases to 266 (ft3/s)-d greater than forecasted releases. Based on gaged streamflow at the Montague site, total directed releases from New York City reservoirs during the report year (column 9 in table 9) were about 6.6 percent more than required for exact forecasting (column 11 in table 9).
A hydrograph comparison of forecasted and computed runoff from the uncontrolled area (fig. 4) indicated that the forecasts were suitable for designing releases from New York City Delaware River Basin reservoirs. Numerical adjustments to the designs were made when needed to compensate for forecast errors. However, because of travel times, the effects of the adjustments on flows at the Montague site were not evident until several days after the design date.
Hydrographs of computed and forecasted uncontrolled runoff components, Delaware River at Montague, New Jersey (U.S. Geological Survey site number 01460440), from August 1 to November 30, 2014. Discharge is shown in cubic feet per second.
Releases From New York City Reservoirs
The ODRM operations data on controlled releases from Pepacton, Cannonsville, and Neversink Reservoirs to the Delaware River were provided by the NYCDEP to the ODRM. These data were collected from calibrated instruments connected to Venturi meters installed in the outlet conduits of the reservoirs.
The USGS streamgaging site on the East Branch Delaware River at Downsville, N.Y. (site number 01417000), is 0.5 miles (mi) downstream from Downsville Dam (fig. 1). Discharge measured at this site includes releases from Pepacton Reservoir, a small amount of seepage, and any runoff that enters the channel between the dam and the streamgage. The drainage area is 371 mi2 at the dam and 372 mi2 at the streamgage. The streamgage records are rated “good,” which means that about 95 percent of the measured daily mean discharges are within 10 percent of the actual discharge.
Figure 5A shows the measured flow from Pepacton Reservoir, including spillway, conservation, and directed releases, as reported by the NYCDEP, compared with the records for the USGS streamgage on the East Branch Delaware River at Downsville, N.Y. (table 13, in back of report; USGS, 2019a) from December 1, 2013, to November 30, 2014. The mean difference is 5.3 percent; 95 percent of the daily differences between the streamgage readings and New York City records are within 24 percent. Greater differences rarely occur and can be due to rainfall. Instruments connected to the Venturi meters were recalibrated periodically by the NYCDEP to improve the accuracy of the recorded flow data.
Graphs showing New York City-measured mean flow compared with computed mean flow records of U.S. Geological Survey (USGS) streamgaging sites, with both sets of flow data shown in cubic feet per second, downstream from their respective reservoirs: (A) site number 01417000, East Branch Delaware River at Downsville, New York (N.Y.), downstream from Pepacton Reservoir (data from USGS, 2019a); (B) site number 01425000, West Branch Delaware River at Stilesville N.Y., downstream from Cannonsville Reservoir (data from USGS, 2019b); and (C) site number 01436000, Neversink River at Neversink, N.Y., downstream from Neversink Reservoir (data from USGS, 2019c), for December 1, 2013, through November 30, 2014.
The USGS streamgaging site on the West Branch Delaware River at Stilesville, N.Y. (USGS site number 01425000; fig. 1), is 1.4 mi downstream from Cannonsville Dam. Discharge measured at this site includes releases from Cannonsville Reservoir and runoff from 2 mi2 of drainage area between the dam and the streamgage. The drainage area is 454 mi2 at the dam and 456 mi2 at the streamgage. The streamgage records are rated “fair,” which means that about 95 percent of the daily mean discharges are within 15 percent of the actual discharge. The records include runoff from the area between the dam and the streamgage and seepage near the base of the dam.
Figure 5B shows the releases from Cannonsville Reservoir (including spillway, conservation, and directed releases), reported by New York City, compared with records for the USGS streamgage on the West Branch Delaware River at Stilesville, N.Y. (table 14, in back of report; USGS, 2019b), from December 1, 2013, to November 30, 2014. The mean difference is 6.5 percent, and 95 percent of the daily differences between the streamgage readings and New York City records are within 17 percent. The most significant differences between the measured flows are primarily at lower flow rates.
The USGS streamgaging site on the Neversink River at Neversink, N.Y. (site number 01436000), is 1,650 ft downstream from the Neversink Dam (fig. 1). Discharge measured at this streamgage includes releases from Neversink Reservoir and, during storms, a small amount of runoff that originates between the dam and the streamgage. The drainage area is 92.5 mi2 at the dam and 92.6 mi2 at the streamgage. The streamgage records are rated “good,” which means that about 95 percent of the measured daily mean discharges are within 10 percent of the actual discharge.
Figure 5C shows releases from Neversink Reservoir, including spillway, conservation, and directed releases, reported by New York City, compared with the records for the USGS streamgage on the Neversink River at Neversink, N.Y. (table 15, in back of report; USGS, 2019c), from December 1, 2013, to November 30, 2014. The mean difference between the released flow and measured flow is 6.5 percent, and 95 percent of the daily differences between the streamgage readings and New York City records are within 21.0 percent.
Delaware River at Montague, New Jersey
The ODRM’s operations record for the Delaware River at Montague, N.J. (USGS site number 01438500) (table 10), showed 0.6 percent less discharge for the report year than the published USGS record for the streamgage (table 11). Daily values for the two records agreed closely, except during ice-affected periods and the summer vegetation growth season.
Conformance of Operations Under the Amended Decree of the Supreme Court of the United States Entered June 7, 1954
From December 1, 2013, to November 30, 2014, operations of the ODRM were conducted as stipulated by the Decree and the FFMP. Diversions from the Delaware River Basin to the New York City water-supply system did not exceed those authorized by the Decree and the FFMP. New York City released water from its reservoirs at rates directed by the ODRM to meet the applicable flow objective at the Montague site. During the report year, New York City complied fully with all directives and requests of the ODRM. Diversions from the Delaware River Basin by New Jersey were within the limits stipulated by the Decree. New Jersey complied fully with all directives and requests of the ODRM. The IERQ was used in accordance with the FFMP and agreements completed throughout the report year.
Quality of Water in the Delaware River Estuary
This section describes water-quality monitoring programs for the Delaware River estuary during the 2014 report year. Selected data are presented, and water-quality conditions are summarized.
Water-Quality Monitoring Programs
U.S. Geological Survey Continuous Water-Quality Monitoring Program
As part of a long-term program, in cooperation with the DRBC, the USGS operates continuous water-quality monitoring stations at four locations in the Delaware River estuary between the streamgages at Trenton, N.J., and Reedy Island Jetty, Delaware (Del.) (fig. 6).
Map showing location of Delaware River Basin Commission (DRBC) water-quality monitoring sites on the Delaware River estuary. Modified from DRBC (2021). U.S. Geological Survey streamgaging sites (1–4) and DRBC sampling sites (A–N, P–W) are listed.
Continuous water temperature, specific conductance, dissolved oxygen, and pH data were collected at four sites: the Delaware River at Trenton, N.J. (USGS site number 01463500); the Delaware River at Benjamin Franklin Bridge at Philadelphia, Pennsylvania (Pa.) (USGS site number 01467200); the Delaware River at Chester, Pa. (USGS site number 01477050); and the Delaware River at Reedy Island Jetty, Del. (USGS site number 01482800). Continuous turbidity data were also collected at the Trenton and Reedy Island Jetty sites.
The DRBC and others use these data to assess water-quality conditions and track “salt front” movement in the Delaware River estuary. Continuous monitor data are processed and stored in the USGS National Water Information System database (NWIS) (USGS, 2019g) and are available at https://waterdata.usgs.gov/nwis. Selected monitoring data from the 2014 report year are included in this report section.
For this report, station number 01467200 is referred to as “Delaware River at Benjamin Franklin Bridge at Philadelphia, PA” because that was the gage name during the report period from December 1, 2013, to November 30, 2014. The gage was moved 150 feet upstream and renamed “Delaware River at Penns Landing, Philadelphia, PA” in January 2020. The updated name is used in the “References Cited” section to refer to the data as listed on NWIS web at the time of publication.
Delaware River Estuary Boat Run Monitoring Program
Each year, the DBRC contracts with the Delaware Department of Natural Resources and Environmental Control to collect water samples at 22 sites on the Delaware River estuary (fig. 6, sites A–N, P–W) (DRBC, 2021). Samples are collected monthly from April to October. The goals of this program are to provide accurate, precise, and defensible estimates of the surface-water quality of the Delaware River estuary and allow for the assessment of compliance with water-quality standards. Sample analysis includes routine and bacterial parameters, nutrients, heavy metals, chlorophyll-a, dissolved silica, and volatile organics. Water-quality data for these DBRC sampling sites are not presented in this report but are accessible from the DRBC Delaware Estuary Water Quality (Boat Run) Explorer (https://johnyagecic.shinyapps.io/BoatRunExplorer/).
Water Quality During the 2014 Report Year
Streamflow
Streamflow has a major effect on water quality in the Delaware River estuary. Large freshwater inflows commonly result in improved water quality by limiting the upstream movement of seawater and reducing the concentration of dissolved substances. High inflows also aid in maintaining lower water temperatures during warm weather and support higher concentrations of dissolved oxygen. Under certain conditions, however, high streamflows can transport large quantities of nutrients to the estuary, which can result in excessive algae levels.
Streamflow from the Delaware River Basin upstream from the Trenton, N.J., site is the primary source of freshwater inflow to the Delaware River estuary. During the report year, monthly mean streamflow measured at the Delaware River at Trenton, N.J., streamgage (USGS site number 01463500) was highest during May 2014 (24,568 ft3/s; table 16, in back of report) and lowest during September 2014 (3,295 ft3/s; table 16). Long-term monthly mean streamflow was computed for October 1912 through November 2013 (USGS, 2019f). Monthly mean streamflows were less than the long-term mean monthly streamflows in December 2013, February and March 2014, and from August through November 2014. The greatest percentage of flow deficiency was in November 2014, when the monthly mean streamflow was 35 percent of the long-term mean monthly flow. The highest daily mean streamflow during the report year was 74,900 ft3/s on May 1, 2014, and the lowest daily mean streamflow was 2,610 ft3/s on October 8, 2014 (table 16).
Water Temperature
Water temperature influences water quality by affecting the various physical, chemical, and biological properties of water (USGS, 2020c). Increases in water temperature usually have detrimental effects on water quality by decreasing the saturation level of dissolved oxygen and increasing the biological activity of aquatic organisms. Although the primary factors that affect water temperature in the Delaware River estuary are climatic, various kinds of water use, especially powerplant cooling, can have substantial effects.
Water temperature data for the Benjamin Franklin Bridge site were collected almost continuously from April to November 2014. The procedures used to create figure 7 of this report were started for the 2011 report (DiFrenna and others, 2020). The available long-term mean daily temperature data were retrieved from the NWIS database for April through November; the mean value was computed for each month. Long-term mean water temperatures were computed using data for 1964 to 2014 (fig. 7). In September and October 2014, the monthly mean temperatures were greater than the long-term mean monthly temperatures (fig. 7). Monthly mean temperatures were less than the respective long-term mean temperatures in April–August and in November 2014 (fig. 7). The maximum daily mean water temperature of 26.4 degrees Celsius was recorded on July 16, 2014 (USGS, 2020d).
Bar chart showing monthly mean water temperatures in 2014 and long-term mean monthly water temperatures from 1964 to 2014, for April–November in the Delaware River estuary at Benjamin Franklin Bridge, Philadelphia, Pennsylvania. Water temperatures are given in degrees Celsius.
Specific Conductance and Chloride
Specific conductance is a measure of the capacity of water to conduct electrical current and is a function of the types and quantities of dissolved substances in water (U.S. Environmental Protection Agency, 2016). As concentrations of dissolved ions increase, the specific conductance of the water also increases. Specific conductance measurements are effective indicators of dissolved solids content and total ion concentrations, including chloride. Seawater and some artificial constituents can cause the specific conductance of estuary water to increase substantially. Dilution associated with high freshwater inflows results in decreased levels of dissolved solids and lower specific conductance, whereas low inflows have the opposite effect.
The upstream movement of seawater and the accompanying increase in chloride concentrations is a concern for water supplies obtained from the Delaware River estuary (Kauffman and others, 2009). Water with chloride concentrations greater than 250 milligrams per liter (mg/L) is considered undesirable for domestic use, and water with concentrations exceeding 50 mg/L is unsatisfactory for chemically sensitive consumers and some industrial processes. Chloride concentrations in the estuary increase in a downstream direction.
The Reedy Island Jetty site measured specific conductance, not chloride concentrations. Chloride concentrations at the Chester site (table 17, in back of report; USGS, 2020f) were measured by Kimberly-Clark Chester Operations. The DRBC provided those data; they are not derived from specific conductance data.
The greatest daily maximum specific conductance at the Reedy Island Jetty site was 24,600 microsiemens per centimeter at 25 degrees Celsius (µS/cm at 25 °C) on November 17, 2014 (table 18, in back of report). The daily maximum specific conductance during the report year exceeded 3,780 µS/cm at 25 °C on approximately 96 percent of the 362 days measured during the 2014 report year. The lowest daily minimum specific conductance was 264 µS/cm at 25 °C on May 1 and 2, 2014. The daily minimum specific conductance exceeded 3,780 µS/cm at 25 °C on 57 percent of the 362 days with measured specific conductance values in the 2014 report year.
The greatest daily maximum chloride concentration at the Chester site was 490 mg/L on October 12 and 13, 2014 (table 17). During the report year, daily maximum concentrations exceeded 50 mg/L on about 76 percent of the days. The lowest daily minimum chloride concentration was 35 mg/L on April 23, 2014. Daily minimum concentrations exceeded 50 mg/L on about 59 percent of the days. Chloride concentrations were relatively high from December 1, 2013, to mid-January 2014, from early February to mid-March 2014, in early April 2014, and from mid-August through November 30, 2014 (table 17), when daily minimum concentrations exceeded 50 mg/L on most days.
Dissolved Oxygen
Dissolved oxygen in water is necessary for the respiratory processes of aquatic organisms and chemical reactions in aquatic environments (USGS, 2020a). Fish and many other clean-water species consistently require relatively high dissolved-oxygen concentrations. The primary source of dissolved oxygen in the Delaware River estuary is diffusion from the atmosphere and, to a lesser extent, the photosynthetic activity of aquatic plants. The principal factors that affect dissolved-oxygen concentrations in the estuary are water temperature, biochemical oxygen demand, freshwater inflow, phytoplankton, turbidity, salinity, and tidal and wind-driven mixing.
The USGS has measured dissolved oxygen concentrations at several sites on the Delaware River estuary since 1961. Two of these sites, the Benjamin Franklin Bridge site and the Chester site, have nearly continuous records and are in the reach of the estuary most affected by effluent discharges, which can lead to reduced dissolved oxygen concentrations because of increasing biological oxygen demand by aerobic bacteria in water. For these sites, the daily mean and minimum daily mean dissolved-oxygen concentrations for the 3-month period of July–September, during the 1965–2014 report years, are shown in figure 8.
Although dissolved-oxygen concentrations increased considerably over these 50 years, yearly mean concentrations can vary substantially. Due to technological changes and other factors, the process used to calculate mean dissolved-oxygen concentrations and those data values have changed slightly over time. The procedures used to create figure 8 in this report have been used since the 2009–10 Delaware River Master report (Russell and others, 2019). The available mean and minimum daily dissolved-oxygen concentration data were downloaded from the NWIS database for July, August, and September. The average mean and average minimum dissolved-oxygen concentrations of the daily values were computed over those 3 months for each report year.
Dissolved oxygen concentrations in the Delaware River estuary are generally greatest near the Trenton site and decrease in a downstream direction. Concentrations commonly reach minimum levels in an area just downstream from the Benjamin Franklin Bridge. During the report year, the lowest recorded daily mean concentration was 5.1 mg/L on August 15, 17, 18, 20, 21, 24, 25, and September 5 and 8, 2014 (table 19, in back of report; USGS, 2020d). Daily mean dissolved oxygen concentrations were consistently 6.0 mg/L or greater from April 1 to July 14, 2014, and October 5 to November 30, 2014. At the Chester site, the lowest recorded daily mean dissolved-oxygen concentration was 4.9 mg/L on September 2, 4, 6, and 7, 2014 (table 20, in back of report; USGS, 2020e).
Histograms of half-hourly dissolved-oxygen concentrations during the critical summer period (July 1–September 30, 2014) at the Benjamin Franklin Bridge and Chester sites are presented in figure 9. During the 2014 critical summer period, half-hourly dissolved-oxygen concentrations were 4.0 mg/L or less for 0 days (0 percent of the time) at the Benjamin Franklin Bridge site and a combined total of 1.1 days (1.2 percent of the time) at the Chester site (USGS, 2020d, e18).
Graphs showing the daily mean and minimum daily mean dissolved-oxygen concentrations (in milligrams per liter) averaged from the months of July–September, annually, at two sites on the Delaware River estuary, 1965–2014, at (A) Delaware River at Benjamin Franklin Bridge at Philadelphia, Pennsylvania (Pa.) (U.S. Geological Survey [USGS] site number 01467200) and (B) Delaware River at Chester, Pa. (USGS site number 01477050).
Graphs showing percent distribution of quarter-hourly dissolved-oxygen concentrations (in milligrams per liter) at two sites on the Delaware River estuary, from July to September 2014 for (A) Delaware River at Benjamin Franklin Bridge at Philadelphia, Pennsylvania (Pa.) (U.S. Geological Survey [USGS] site number 01467200), and (B) Delaware River at Chester, Pa. (USGS site number 01477050).
Hydrogen-Ion Activity (pH)
The pH of a solution is a measure of the effective concentration (activity) of dissolved hydrogen ions. Solutions with a pH less than 7 are acidic, whereas solutions with a pH greater than 7 are basic or alkaline. The pH of uncontaminated surface water generally ranges from 6.5 to 8.5. Major factors affecting the pH of surface water are the geologic composition of the drainage basin and human inputs, including effluent discharges. In addition, photosynthetic activity and dissolved gases, including carbon dioxide, hydrogen sulfide, and ammonia, considerably affect pH. The pH of water determines the solubility (the amount that can be dissolved in the water) and biological availability (the amount that can be used by aquatic life) of chemical constituents such as nutrients (phosphorus, nitrogen, and carbon) and heavy metals (for example, lead, copper, and cadmium; USGS, 2020b).
During the report year, pH was measured seasonally (April–November) at the Benjamin Franklin Bridge and Chester sites and continuously at the Reedy Island Jetty site. During these periods, the ranges of daily median pH measured at these sites are as follows: Benjamin Franklin Bridge, 6.8–7.6; Chester, 6.9–7.4; and Reedy Island Jetty, 7.2–7.8 (USGS, 2020d, e, f). Generally, the pH of water in the Delaware River estuary is lowest near Trenton, N.J., and increases (the water becomes more alkaline) in the downstream direction. The pH of water in the Delaware River estuary between the Benjamin Franklin Bridge and Reedy Island Jetty was not a limiting factor for aquatic health or other beneficial water-uses during the report year.
Tables 1, 3–11, and 13–20
Table 1.
Precipitation in the Delaware River Basin upstream of Montague, New Jersey.[Data provided daily from the National Weather Service, the New York City Department of Environmental Protection, and the Office of the Delaware River Master. in., inches; —, not applicable]
Table 3.
Storage in Pepacton Reservoir, New York, for report year ending November 30, 2014.[Delaware River Master daily operations record; gage reading at 0800 hours; data provided daily through written communication from New York City Department of Environmental Protection. Storage is given in millions of gallons above the elevation of 1,152.00 feet. Add 7,711 million gallons for total contents above the sill of the outlet tunnel at the elevation of 1,126.50 feet. Storage at the spillway level is 140,190 million gallons. —, not applicable; Mgal/d, million gallons per day; ft3/s, cubic foot per second]
Change is calculated as the storage on the last day of each month minus the storage on the first day of each month. The net change for the year is –17,047.0 million gallons. Minimum and maximum storage for December through May is 104,288 and 141,894 million gallons, respectively; minimum and maximum storage for June through November are 86,508 and 141,727 million gallons, respectively.
Table 4.
Storage in Cannonsville Reservoir, New York, for report year ending November 30, 2014.[Delaware River Master daily operations record; gage reading at 0800 hours; data provided daily through written communication from New York City Department of Environmental Protection. Storage is given in millions of gallons above the elevation of 1,040.00 feet. Add 2,584 million gallons for total contents above the sill of the outlet tunnel at the elevation of 1,020.50 feet. Storage at spillway level is 95,706 million gallons. —, not applicable; Mgal/d, million gallons per day; ft3/s, cubic foot per second]
Change is calculated as the storage on the last day of each month minus the storage on the first day of each month. Net change for the year is –22,413.0 million gallons. Minimum and maximum storage for December through May are 66,579 and 99,890 million gallons, respectively; minimum and maximum storage for June through November are 42,542 and 95,113 million gallons, respectively.
Table 5.
Storage in Neversink Reservoir, New York, for report year ending November 30, 2014.[Delaware River Master daily operations record; gage reading at 0800 hours; data provided daily through written communication from by New York City Department of Environmental Protection. Storage is given in millions of gallons above the elevation of 1,319.00 feet. Add 525 million gallons for total contents above the sill of the outlet tunnel at the elevation of 1,314.00 feet. Storage at spillway level is 34,941 million gallons. —, not applicable; Mgal/d, million gallons per day; ft3/s, cubic foot per second]
Change is calculated as the storage on the last day of each month minus the storage on the first day of each month. Net change for year is more than –5,874.0 million gallons. Minimum and maximum storage for December through May is 24,625 and 35,254 million gallons, respectively; minimum and maximum storage for June through November is 22,392 and 35,329 million gallons, respectively.
Table 6.
Diversions to New York City water-supply system for report year ending November 30, 2014.[Delaware River Master daily operations record. Diversions in million gallons per day (Mgal/d) for each 24-hour period beginning 0800 local time. For December 1–May 31, the average is computed beginning June 1, 2013, to the given date. For June 1–November 30, the average is computed beginning June 1, 2014, to the given date. The diversion calculation is computed as authorized within the Decree. —, not applicable]
Table 7.
Consumption of water by New York City, from 1950 to 2014.[Data provided through written communication by New York City Department of Environmental Protection, Bureau of Water Supply. Mgal/d, million gallons per day; Ggal, billion gallons]
Table 8.
Diversions by the State of New Jersey, daily mean discharge, Delaware and Raritan Canal at Port Mercer, New Jersey (U.S. Geological Survey site number 01460440), for report year ending November 30, 2014.[Data from U.S. Geological Survey (2019e). All values except total are in million gallons per day (Mgal/d); total in million gallons (Mgal). —, not applicable; e, estimated]
Table 9.
New York City reservoir release design data, from December 1, 2013, to November 30, 2014.[Delaware River Master daily operations record. The Montague flow objective was 1,750 ft3/s. Column (col.) 1 data were provided by electric utility PPL Corporation; col. 2 data were provided by electric utility Eagle Creek Renewable Energy; col. 3 computed from index stations (fig. 1); col. 4 computed increase in runoff based on quantitative precipitation forecasts; col. 5 = col. 1 + col. 2 + col. 3 + col. 4; col. 6 = design rate − col. 5, when positive, otherwise col. 6 = 0; col. 7 = col. 14 (4 days earlier); col. 8, directed release amount from the Office of the Delaware River Master = col. 6 + col. 7, when positive, otherwise col. 8 =0; col. 9 = col. 7 from table 10; col. 10 = summation of col. 9; col. 11 = flow objective − (col. 9 + col. 10 from table 10) when positive, otherwise col. 11 = 0; col. 12 = summation of col. 11; col. 13 = col. 10 − col. 12; col. 14 = col. 13 divided by −10, limited to ±50 cubic feet per second ; cols. 10, 12, 13, and 14 are accumulated from the previous water year starting June 1, 2011, with these values being reset on June 1, 2012; X, a miscalculation of col. 12 – Col 10 was recorded during the directed release design process; Y, the balancing adjustment was not reset on June 15, 2012. ft3/s, cubic foot per second; (ft3/s)-d, cubic foot per second for a day]