Report of the River Master of the Delaware River for the Period December 1, 2013–November 30, 2014

Open-File Report 2023-1084
Water Availability and Use Science Program
By: , and 

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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

  • Delaware—David Wunsch

  • New Jersey—Michele Siekerka

  • New York—Mark Klotz

  • New York City—Paul Rush

  • 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.

East and West Delaware Tunnels, Delaware Aqueduct, and Delaware River Basin rivers,
                     lakes, and reservoirs are also shown.
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:

  1. controlled releases from the Pepacton, Cannonsville, and Neversink Reservoirs of New York City;

  2. controlled releases from Lake Wallenpaupack on Wallenpaupack Creek to produce hydroelectric power; and

  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]

Level Pepacton Reservoir Cannonsville Reservoir Neversink Reservoir
Elevation (ft) Volume (Mgal) Elevation (ft) Volume (Mgal) Elevation (ft) Volume (Mgal)
Full pool or spillway crest 1,280 1,150 1,440
Point of maximum depletion 1,152 1140,190 1,040 195,706 1,319 134,941
Sill of diversion tunnel 1,143 23,511 31,035 21,020 1,314 2525
Sill of river outlet tunnel 1,126.50 44,200 1,020.5 41,564 1,314 NA
Dead storage 1,800 328 1,680
Table 2.    Elevation and capacities of structures of the Pepacton, Cannonsville, and Neversink Reservoirs.
1

The quantity stored between full pool or spillway crest and the point of maximum depletion.

2

The quantity stored between the point of maximum depletion and the sill of the diversion tunnel.

3

The elevation of the mouth of the inlet channel of the diversion works.

4

The quantity stored between the sill of the diversion tunnel and the sill of the river outlet tunnel.

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.

Levels shown are—spill mitigation (L1), normal (L2), drought watch (L3), drought warning
                        (L4), and drought emergency (L5).
Figure 2.

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.

The graph’s discharge quantities range is from 0 to 4,000 cubic feet per second.
Figure 3.

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]

Releases and runoff Forecasted volume ([ft3/s]-d) Actual volume ([ft3/s]-d)
Lake Wallenpaupack 12,324 12,401
Rio Reservoir 2,977 6,276
Runoff from uncontrolled area 128,261 136,001
Table 12.    Cumulative forecasted and actual release volume from Lake Wallenpaupack and Rio Reservoir, and uncontrolled runoff from July 1 to November 1, 2014.

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.

The graph’s discharge quantities range is from 0 to 8,000 cubic feet per second.
Figure 4.

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.

Mean-flow rates for the graphs are (A) 0–3,000; (B) 0–4,000; and (C) 0–1,400.
Figure 5.

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).

The Delaware River, Delaware Bay, and Schuykill River are shown on the map.
Figure 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).

Temperature on the graph ranges from 0 to 30 degrees Celsius.
Figure 7.

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).

Dissolved oxygen concentration range on the graphs is 0–7 milligrams per liter.
Figure 8.

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 plot dissolved-oxygen concentration range (3.0–11.0 milligrams per liter) and
                           time (0–35 percent).
Figure 9.

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]

Month December 1940 to November 2014 monthly average precipitation (in.) December 2013 to November 2014
Precipitation (in.) Percent of average Excess or deficit precipitation compared with long-term average (in.)
Month Cumulative
December 3.50 3.69 105 0.19 0.19
January 3.02 2.75 91 −0.27 −0.08
February 2.62 3.75 143 1.13 1.05
March 3.40 2.44 72 −0.96 0.09
April 3.77 2.82 75 −0.95 −0.86
May 4.19 4.71 112 0.52 −0.34
June 4.21 5.23 124 1.02 0.68
July 4.18 5.52 132 1.34 2.02
August 4.07 2.75 68 −1.32 0.70
September 4.12 1.36 33 −2.76 −2.06
October 3.71 5.07 137 1.36 −0.70
November 3.72 2.31 62 −1.41 −2.11
Total 44.51 42.40 95
Table 1.    Precipitation in the Delaware River Basin upstream of Montague, New Jersey.

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]

Day Dec. Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov.
1 104,288 116,763 127,216 120,225 122,756 138,719 139,693 140,468 132,344 118,579 104,192 93,572
2 104,479 117,064 126,883 119,936 124,153 139,252 139,509 140,209 131,987 118,090 103,704 93,110
3 104,606 117,283 126,533 119,614 125,539 139,675 139,345 140,116 131,576 117,719 103,215 92,709
4 104,685 117,400 126,097 119,325 126,831 140,264 139,345 140,431 131,185 117,132 102,727 92,279
5 104,827 117,602 125,870 119,019 128,146 140,671 139,252 140,653 130,777 116,663 102,383 91,792
6 105,050 118,293 125,835 118,613 129,430 140,690 139,032 140,523 130,369 116,177 101,945 91,394
7 105,288 120,684 125,471 118,293 130,475 140,542 138,848 140,264 129,925 115,709 101,492 90,908
8 105,352 121,591 125,140 117,956 131,363 140,486 138,627 139,822 129,501 115,210 101,086 90,614
9 105,304 122,275 124,794 117,686 132,219 140,449 138,443 139,509 129,042 114,694 100,683 90,233
10 105,241 123,050 124,447 117,350 133,096 140,468 138,241 139,124 128,585 114,180 100,234 89,884
11 105,209 123,876 124,065 117,031 133,815 140,357 138,058 138,645 128,110 113,683 99,784 89,491
12 105,399 126,516 123,670 116,880 134,750 140,227 137,857 138,076 127,653 113,206 99,351 89,257
13 105,446 128,146 123,325 116,981 135,421 140,024 137,730 137,601 127,547 112,728 98,936 88,980
14 105,383 129,183 123,187 116,930 136,073 139,877 138,369 138,040 127,163 112,250 98,491 88,720
15 105,336 130,334 122,860 116,863 136,763 139,840 138,811 138,388 126,726 111,792 98,061 88,460
16 105,241 131,043 122,584 116,830 140,301 139,712 139,124 138,829 126,236 111,301 97,908 88,172
17 105,446 131,737 122,395 116,730 141,580 141,506 139,087 139,068 125,747 110,794 97,709 87,955
18 105,320 132,200 122,104 116,511 141,709 141,894 138,976 139,105 125,278 110,306 97,725 87,869
19 105,209 132,487 121,797 116,227 141,468 141,580 138,885 139,087 124,759 109,916 97,740 87,739
20 105,066 132,505 121,609 116,110 141,209 141,320 138,866 138,682 124,291 109,396 97,725 87,466
21 105,002 132,361 121,368 116,093 140,968 141,005 138,682 138,205 123,825 108,895 97,298 87,352
22 106,596 132,200 121,436 116,060 140,634 140,727 138,461 137,730 123,376 108,443 96,825 87,037
23 108,813 131,773 121,540 115,993 140,431 140,727 138,168 136,981 122,912 107,991 96,400 86,708
24 110,582 131,434 121,557 115,959 140,153 140,616 137,875 136,690 122,464 107,525 96,295 86,523
25 111,628 130,830 121,300 115,809 139,785 140,708 137,893 136,091 121,968 107,060 96,053 86,580
26 112,299 130,387 121,043 116,076 139,455 140,653 141,580 135,475 121,522 106,612 95,720 86,508
27 112,843 129,855 120,787 115,993 139,124 140,616 141,727 134,877 120,975 106,100 95,373 86,737
28 113,453 129,306 120,480 115,826 138,958 140,431 141,246 134,426 120,463 105,605 95,040 87,066
29 114,047 128,743 116,194 138,737 140,153 140,857 133,977 120,004 105,145 94,755 87,138
30 115,426 128,128 118,107 138,461 139,914 140,597 133,437 119,512 104,669 94,366 86,980
31 116,311 127,618 121,009 139,822 132,826 119,019 93,976
Change1 12,023 10,855 −6,736 784 15,705 1,103 904 −7,642 −13,325 −13,910 −10,216 −6,592
Equivalent change2 (Mgal/d) 387.8 350.2 −240.6 25.3 523.5 35.6 30.1 −246.5 −429.8 −463.7 −329.5 −219.7
Equivalent change3 (ft3/s) 600 542 −372 39.1 810 55.1 46.6 −381 −665 −717 −510 −340
Table 3.    Storage in Pepacton Reservoir, New York, for report year ending November 30, 2014.
1

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.

2

The net equivalent for the year is –46.7 million gallons per day.

3

The net equivalent for the year is –72.2 cubic feet per second.

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]

Day Dec. Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov.
1 66,579 83,634 87,652 82,406 86,525 95,037 95,113 94,413 88,526 76,122 55,933 49,212
2 67,037 84,154 87,175 82,030 87,898 95,265 94,748 94,444 88,237 75,887 55,030 49,142
3 67,437 84,516 86,698 81,683 89,073 95,371 94,322 94,459 87,970 75,555 54,217 49,060
4 67,808 84,646 86,250 81,264 90,153 95,478 94,276 94,596 87,710 75,265 53,517 48,937
5 68,351 84,704 86,005 80,861 91,127 95,539 94,139 94,611 87,421 75,058 52,910 48,815
6 68,987 85,109 85,759 80,474 92,329 95,676 93,744 94,550 87,204 74,837 52,071 48,848
7 69,582 87,565 85,499 79,811 93,227 95,867 93,364 94,428 86,886 74,602 51,138 48,603
8 69,953 88,057 85,528 79,134 93,561 95,980 92,938 94,246 86,409 74,368 50,227 48,303
9 70,311 88,587 85,557 78,774 93,637 96,205 92,527 94,200 85,875 74,022 49,609 47,880
10 70,550 89,165 85,629 78,360 93,744 96,317 92,131 94,139 85,340 73,569 48,892 47,436
11 70,656 89,712 85,672 78,097 93,744 96,462 91,736 93,713 84,964 73,092 48,147 46,924
12 70,669 91,736 85,687 78,097 93,866 96,462 91,325 93,485 84,617 72,311 47,469 46,379
13 70,523 92,618 85,701 78,650 93,987 96,414 91,401 93,029 84,342 71,437 46,824 45,801
14 70,523 93,090 85,788 78,968 93,972 96,269 92,390 92,968 84,053 70,497 46,124 45,312
15 70,602 93,987 85,788 79,065 93,911 96,157 93,090 92,831 83,490 69,596 45,412 44,934
16 70,629 94,474 85,658 79,258 96,350 95,996 93,303 92,786 82,854 68,854 45,701 44,567
17 70,430 94,763 85,369 79,341 97,637 99,166 93,394 92,694 82,232 68,139 46,435 44,189
18 70,271 94,869 85,036 79,355 97,878 99,890 93,759 92,527 81,582 67,241 46,713 43,888
19 70,245 94,900 84,501 79,410 97,701 99,441 94,094 92,329 80,888 66,528 46,880 43,644
20 70,338 94,763 84,097 79,424 97,412 98,957 94,170 92,070 80,419 65,599 46,980 43,372
21 70,616 94,550 83,793 79,590 97,058 98,426 94,109 91,827 80,060 64,619 47,046 43,277
22 72,483 94,109 83,620 79,755 96,671 97,943 93,866 91,583 79,686 63,701 47,147 42,930
23 75,542 93,561 83,692 79,811 96,382 97,734 93,577 91,309 79,272 62,810 47,236 42,584
24 77,572 93,014 83,677 79,880 96,060 97,508 93,455 91,279 78,996 61,906 47,525 42,542
25 78,885 92,420 83,533 79,880 95,554 97,170 93,364 91,036 78,664 61,218 47,869 42,783
26 79,755 91,842 83,287 79,838 95,250 96,832 93,759 90,594 78,332 60,781 48,136 43,004
27 80,613 91,264 83,027 79,797 95,219 96,494 94,368 90,275 78,001 59,987 48,381 43,435
28 81,062 90,670 82,767 79,755 95,143 96,269 94,413 90,093 77,655 59,059 48,603 43,911
29 81,308 90,001 80,253 94,946 95,996 94,307 89,712 77,310 58,070 48,804 44,089
30 82,189 89,332 81,698 94,900 95,691 94,352 89,530 76,923 56,971 48,970 44,166
31 83,013 88,404 84,617 95,417 89,073 76,468 49,119
Change1 16,434 4,770 −4,885 2,211 8,375 380 −761 −5,340 −12,058 −19,151 −6,814 −5,046
Equivalent change2 (Mgal/d) 530.1 153.9 −174.5 71.3 279.2 12.3 −25.4 −172.3 −389 −638.4 −219.8 −168.2
Equivalent change3 (ft3/s) 820 238 −270 110.3 432 19 −39.3 −267 −602 −988 −340 −260
Table 4.    Storage in Cannonsville Reservoir, New York, for report year ending November 30, 2014.
1

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.

2

The net equivalent for the year is –61.4 million gallons per day.

3

The net equivalent for the year is –95.0 cubic feet per second.

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]

Day Dec. Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov.
1 29,275 32,781 30,721 26,868 26,684 33,929 34,828 34,577 34,497 30,164 27,176 24,822
2 29,387 32,866 30,762 26,864 27,060 34,281 34,833 34,492 34,473 29,823 27,141 24,523
3 29,509 32,771 30,799 26,829 27,430 34,321 34,837 34,582 34,419 29,509 27,111 24,242
4 29,575 32,647 30,657 26,578 27,844 34,330 34,715 34,557 34,345 29,181 27,090 23,963
5 29,661 32,705 30,533 26,329 28,207 34,306 34,759 34,591 34,281 28,959 27,107 23,653
6 29,810 32,866 30,538 26,068 28,508 34,286 34,616 34,513 34,101 28,769 27,090 23,385
7 30,009 33,553 30,542 25,809 28,650 34,253 34,621 34,414 34,018 28,738 27,064 23,187
8 30,146 33,403 30,227 25,562 29,057 34,330 34,626 34,243 33,939 28,694 27,039 23,004
9 30,273 33,221 30,232 25,557 29,616 34,301 34,660 34,096 33,853 28,504 27,026 22,818
10 30,350 32,933 30,259 25,545 29,995 34,276 34,675 34,062 33,780 28,315 27,009 22,630
11 30,401 32,943 29,914 25,345 30,324 34,384 34,562 34,096 33,698 28,158 26,988 22,431
12 30,442 34,468 29,571 25,197 30,762 34,492 34,587 34,106 33,465 28,105 26,962 22,427
13 30,401 34,931 29,159 25,027 31,132 34,404 34,306 34,101 33,427 28,071 26,923 22,408
14 30,346 34,936 28,879 24,789 31,512 34,340 34,873 34,863 33,369 28,049 26,897 22,408
15 30,442 34,966 28,884 24,625 31,873 34,194 34,803 34,996 33,302 28,005 26,872 22,400
16 30,487 34,892 28,778 24,649 32,848 34,121 34,621 35,329 33,235 27,957 26,919 22,392
17 30,510 34,655 28,592 24,670 33,062 35,254 34,448 35,130 33,163 27,909 27,077 22,392
18 30,433 34,325 28,451 24,686 33,005 35,244 34,321 35,070 33,101 27,862 27,102 22,501
19 30,355 33,988 28,460 24,670 32,958 35,041 34,276 35,060 32,890 27,809 27,107 22,568
20 30,255 33,620 28,469 24,719 32,871 34,976 34,267 35,041 32,657 27,757 27,094 22,595
21 30,204 33,254 28,478 24,780 32,762 35,021 34,291 35,016 32,430 27,719 27,081 22,611
22 30,447 32,834 28,526 24,826 32,624 35,095 34,325 35,001 32,396 27,658 27,090 22,615
23 31,113 32,377 28,596 24,879 32,757 35,135 34,345 34,863 32,330 27,606 26,936 22,630
24 31,765 31,925 28,623 24,924 32,876 35,110 34,257 34,749 32,264 27,554 26,846 22,665
25 31,981 31,658 28,228 24,949 32,972 35.105 34,047 34,734 32,189 27,507 26,651 22,969
26 32,169 31,652 27,831 24,981 33,081 35,070 34,281 34,710 31,990 27,442 26,427 23,100
27 32,173 31,545 27,417 24,998 33,201 35,045 34,340 34,680 31,771 27,395 26,169 23,195
28 32,184 31,341 27,048 25,023 33,288 35,016 34,443 34,680 31,541 27,339 25,913 23,286
29 32,321 31,141 25,097 33,369 34,966 34,492 34,650 31,211 27,288 25,650 23,346
30 32,667 31,021 25,470 33,461 34,892 34,533 34,591 30,850 27,227 25,379 23,401
31 32,824 30,877 26,257 34,853 34,547 30,501 25,106
Change1 3549 −1,904 −3,673 −611 6777 924 −295 −30.0 −3,996 −2,937 −2,070 −1,421
Equivalent change2 (Mgal/d) 114.5 −61.4 −131.2 −19.7 225.9 29.8 −9.8 −1.0 −128.9 −97.9 −66.8 −47.4
Equivalent change3 (ft3/s) 177 −95.0 −203 −30.5 349 46.1 −15.2 −2.0 −199 −151 −103 −73.0
Table 5.    Storage in Neversink Reservoir, New York, for report year ending November 30, 2014.
1

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.

2

The net equivalent for the year is–16.1 million gallons per day.

3

The net equivalent for year is –24.9 cubic feet per second.

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]

Date East Delaware Tunnel (Mgal/d) West Delaware Tunnel (Mgal/d) Neversink Tunnel (Mgal/d) Average (Mgal/d) from June 1
12/1/2013 448 273 0 620
12/2/2013 451 273 0 620
12/3/2013 426 250 0 620
12/4/2013 299 0 0 619
12/5/2013 299 0 0 617
12/6/2013 399 187 0 617
12/7/2013 448 273 0 617
12/8/2013 431 253 0 618
12/9/2013 446 276 0 618
12/10/2013 308 400 0 619
12/11/2013 180 411 0 619
12/12/2013 208 440 94 619
12/13/2013 368 311 115 620
12/14/2013 398 273 0 620
12/15/2013 364 250 0 620
12/16/2013 0 427 0 619
12/17/2013 237 311 96 619
12/18/2013 350 274 152 620
12/19/2013 350 115 149 620
12/20/2013 336 0 129 619
12/21/2013 0 0 0 616
12/22/2013 0 0 0 613
12/23/2013 328 223 26 613
12/24/2013 353 302 130 614
12/25/2013 353 303 22 614
12/26/2013 353 99 151 614
12/27/2013 103 361 131 614
12/28/2013 0 436 0 613
12/29/2013 0 437 0 613
12/30/2013 5 354 22 611
12/31/2013 301 184 129 611
Total 8,542 7,696 1,346
1/1/2014 303 181 19 611
1/2/2014 303 293 167 612
1/3/2014 273 224 149 612
1/4/2014 206 302 0 611
1/5/2014 206 302 0 611
1/6/2014 205 302 0 610
1/7/2014 205 303 328 611
1/8/2014 205 12 351 611
1/9/2014 0 0 397 610
1/10/2014 0 0 131 608
1/11/2014 0 0 0 605
1/12/2014 0 0 0 603
1/13/2014 0 0 263 601
1/14/2014 0 0 297 600
1/15/2014 0 0 298 599
1/16/2014 0 0 414 598
1/17/2014 0 0 447 597
1/18/2014 0 0 447 597
1/19/2014 0 0 447 596
1/20/2014 156 0 447 596
1/21/2014 156 0 447 596
1/22/2014 289 0 447 597
1/23/2014 343 0 460 597
1/24/2014 400 0 265 598
1/25/2014 401 0 0 597
1/26/2014 401 0 103 596
1/27/2014 400 0 243 597
1/28/2014 400 0 223 597
1/29/2014 400 0 165 597
1/30/2014 400 189 210 597
1/31/2014 342 236 206 598
Total 5,994 2,344 7,371
2/1/2014 259 236 0 598
2/2/2014 260 236 20 597
2/3/2014 400 236 190 598
2/4/2014 400 236 170 599
2/5/2014 158 295 0 599
2/6/2014 450 301 2 599
2/7/2014 401 5 354 600
2/8/2014 401 0 0 599
2/9/2014 401 0 2 598
2/10/2014 401 0 352 599
2/11/2014 401 0 353 600
2/12/2014 401 0 443 601
2/13/2014 401 0 376 601
2/14/2014 401 0 0 600
2/15/2014 306 0 129 600
2/16/2014 300 0 190 599
2/17/2014 301 0 152 599
2/18/2014 300 191 0 598
2/19/2014 300 64 0 598
2/20/2014 300 0 0 596
2/21/2014 278 0 0 595
2/22/2014 208 0 0 594
2/23/2014 209 0 2 592
2/24/2014 400 0 428 593
2/25/2014 400 0 430 594
2/26/2014 400 0 404 595
2/27/2014 400 0 404 596
2/28/2014 400 0 204 596
Total 9,637 1,800 4,605
3/1/2014 400 0 0 595
3/2/2014 400 0 21 594
3/3/2014 406 0 262 595
3/4/2014 400 0 265 595
3/5/2014 400 0 264 595
3/6/2014 400 233 263 596
3/7/2014 400 276 243 597
3/8/2014 383 16 0 597
3/9/2014 396 0 3 596
3/10/2014 399 0 207 596
3/11/2014 400 0 207 596
3/12/2014 400 82 238 596
3/13/2014 413 253 299 598
3/14/2014 400 301 209 599
3/15/2014 400 259 0 599
3/16/2014 400 302 0 599
3/17/2014 400 302 0 600
3/18/2014 400 302 0 600
3/19/2014 400 302 0 600
3/20/2014 399 302 0 601
3/21/2014 399 302 0 601
3/22/2014 399 302 0 601
3/23/2014 399 302 0 602
3/24/2014 383 302 0 602
3/25/2014 0 288 0 601
3/26/2014 305 292 0 601
3/27/2014 400 300 0 601
3/28/2014 400 301 0 602
3/29/2014 1 301 0 601
3/30/2014 4 302 0 600
3/31/2014 205 303 0 599
Total 10,891 6,225 2,481
4/1/2014 201 303 0 599
4/2/2014 202 302 0 599
4/3/2014 202 302 0 598
4/4/2014 100 303 0 598
4/5/2014 0 18 0 596
4/6/2014 5 0 0 594
4/7/2014 206 187 0 593
4/8/2014 202 201 0 593
4/9/2014 205 8 0 592
4/10/2014 206 0 0 590
4/11/2014 221 0 0 589
4/12/2014 396 0 0 589
4/13/2014 383 0 0 588
4/14/2014 51 0 0 586
4/15/2014 233 0 0 585
4/16/2014 177 0 249 585
4/17/2014 51 0 393 584
4/18/2014 154 0 329 584
4/19/2014 182 0 298 584
4/20/2014 178 0 298 583
4/21/2014 400 0 298 584
4/22/2014 401 0 3 583
4/23/2014 500 50 0 583
4/24/2014 500 196 0 583
4/25/2014 500 58 0 583
4/26/2014 500 0 0 583
4/27/2014 300 145 0 582
4/28/2014 301 201 0 582
4/29/2014 301 51 0 582
4/30/2014 25 0 0 580
Total 7,283 2,325 1,868
5/1/2014 0 0 146 579
5/2/2014 0 0 232 578
5/3/2014 0 0 208 576
5/4/2014 0 0 199 575
5/5/2014 251 0 134 575
5/6/2014 301 0 148 574
5/7/2014 301 0 3 574
5/8/2014 301 0 153 573
5/9/2014 303 0 148 573
5/10/2014 449 0 0 573
5/11/2014 448 0 0 572
5/12/2014 449 0 152 572
5/13/2014 420 119 152 573
5/14/2014 449 216 152 573
5/15/2014 449 274 149 574
5/16/2014 144 25 149 573
5/17/2014 253 0 0 573
5/18/2014 487 0 294 573
5/19/2014 472 0 258 574
5/20/2014 499 0 92 574
5/21/2014 432 101 0 574
5/22/2014 400 0 0 573
5/23/2014 400 0 0 573
5/24/2014 288 225 0 572
5/25/2014 250 302 0 572
5/26/2014 251 302 0 572
5/27/2014 362 221 0 572
5/28/2014 439 273 87 573
5/29/2014 376 302 134 574
5/30/2014 307 302 64 574
5/31/2014 297 302 64 574
Total 9,778 2,964 3,118
6/1/2014 300 302 0 602
6/2/2014 299 302 0 602
6/3/2014 300 85 202 597
6/4/2014 300 236 0 582
6/5/2014 300 302 225 631
6/6/2014 300 301 0 626
6/7/2014 300 301 0 622
6/8/2014 300 301 0 620
6/9/2014 300 301 0 617
6/10/2014 297 301 132 629
6/11/2014 300 301 3 626
6/12/2014 300 6 396 633
6/13/2014 74 0 226 607
6/14/2014 0 0 436 595
6/15/2014 0 134 372 589
6/16/2014 338 99 302 598
6/17/2014 489 0 212 604
6/18/2014 485 0 192 608
6/19/2014 319 0 102 599
6/20/2014 396 222 32 601
6/21/2014 396 231 0 602
6/22/2014 400 234 0 604
6/23/2014 400 38 134 602
6/24/2014 99 0 199 590
6/25/2014 0 0 116 571
6/26/2014 493 268 152 584
6/27/2014 500 301 0 592
6/28/2014 500 301 0 599
6/29/2014 500 13 0 596
6/30/2014 500 0 0 593
Total 9,485 4,880 3,433
7/1/2014 500 0 117 594
7/2/2014 481 0 106 594
7/3/2014 82 0 256 586
7/4/2014 0 0 303 578
7/5/2014 304 0 228 576
7/6/2014 422 0 179 577
7/7/2014 494 0 211 581
7/8/2014 500 0 229 584
7/9/2014 501 0 115 585
7/10/2014 501 244 0 589
7/11/2014 501 33 0 588
7/12/2014 401 224 0 589
7/13/2014 174 102 0 582
7/14/2014 0 0 267 574
7/15/2014 0 0 273 568
7/16/2014 0 0 259 561
7/17/2014 0 0 92 551
7/18/2014 1 0 0 540
7/19/2014 304 0 0 535
7/20/2014 304 0 0 530
7/21/2014 301 0 0 526
7/22/2014 426 0 140 526
7/23/2014 450 0 140 528
7/24/2014 451 0 0 526
7/25/2014 451 193 0 528
7/26/2014 451 39 0 528
7/27/2014 451 0 0 526
7/28/2014 451 214 0 529
7/29/2014 451 4 0 527
7/30/2014 451 210 0 530
7/31/2014 451 288 0 533
Total 10,255 1,551 2,915
8/1/2014 450 5 0 532
8/2/2014 450 0 0 531
8/3/2014 450 0 0 529
8/4/2014 450 0 0 528
8/5/2014 450 0 152 529
8/6/2014 450 0 0 528
8/7/2014 450 178 0 529
8/8/2014 450 228 0 532
8/9/2014 450 228 0 534
8/10/2014 450 58 0 533
8/11/2014 449 0 151 534
8/12/2014 21 30 0 528
8/13/2014 448 0 0 527
8/14/2014 450 264 0 529
8/15/2014 450 298 0 532
8/16/2014 450 298 0 535
8/17/2014 450 298 0 538
8/18/2014 450 297 152 542
8/19/2014 450 98 162 544
8/20/2014 450 0 151 545
8/21/2014 450 0 0 544
8/22/2014 450 0 0 543
8/23/2014 450 0 0 541
8/24/2014 450 0 0 540
8/25/2014 450 0 151 541
8/26/2014 450 0 152 542
8/27/2014 450 0 155 543
8/28/2014 450 0 280 545
8/29/2014 437 0 307 547
8/30/2014 450 0 303 549
8/31/2014 450 0 303 551
Total 13,505 2,280 2,419
9/1/2014 450 0 303 554
9/2/2014 450 0 303 556
9/3/2014 450 0 303 558
9/4/2014 450 0 189 559
9/5/2014 450 0 156 559
9/6/2014 450 0 0 558
9/7/2014 450 0 0 557
9/8/2014 450 0 142 557
9/9/2014 450 0 138 557
9/10/2014 450 0 138 558
9/11/2014 450 193 0 559
9/12/2014 415 228 0 559
9/13/2014 451 227 0 561
9/14/2014 451 227 0 562
9/15/2014 450 74 0 561
9/16/2014 450 0 0 560
9/17/2014 450 214 0 561
9/18/2014 379 226 0 562
9/19/2014 450 226 0 563
9/20/2014 450 226 0 564
9/21/2014 450 225 0 565
9/22/2014 418 225 0 565
9/23/2014 450 230 0 566
9/24/2014 450 0 0 565
9/25/2014 450 0 0 564
9/26/2014 450 248 0 565
9/27/2014 450 280 0 567
9/28/2014 450 279 0 568
9/29/2014 449 279 0 570
9/30/2014 450 278 0 571
Total 13,363 3,885 1,672
10/1/2014 450 278 0 572
10/2/2014 450 277 0 573
10/3/2014 449 277 0 575
10/4/2014 400 277 0 575
10/5/2014 401 276 0 576
10/6/2014 401 280 0 577
10/7/2014 401 280 0 578
10/8/2014 401 6 0 577
10/9/2014 401 0 0 575
10/10/2014 401 0 0 574
10/11/2014 401 0 0 573
10/12/2014 401 0 0 571
10/13/2014 401 0 0 570
10/14/2014 401 0 0 569
10/15/2014 401 0 0 568
10/16/2014 399 0 0 566
10/17/2014 0 0 0 562
10/18/2014 0 0 0 558
10/19/2014 0 0 0 554
10/20/2014 375 0 0 553
10/21/2014 498 0 0 553
10/22/2014 497 0 214 554
10/23/2014 486 0 301 555
10/24/2014 494 0 303 557
10/25/2014 493 0 303 559
10/26/2014 460 0 303 560
10/27/2014 472 0 303 561
10/28/2014 366 0 303 562
10/29/2014 494 0 303 564
10/30/2014 494 0 303 565
10/31/2014 494 0 303 567
Total 12,182 1,951 2,939
11/1/2014 515 0 315 568
11/2/2014 493 0 303 570
11/3/2014 493 0 303 571
11/4/2014 493 0 303 573
11/5/2014 493 0 303 574
11/6/2014 489 0 220 575
11/7/2014 400 0 203 575
11/8/2014 400 0 203 575
11/9/2014 400 0 203 576
11/10/2014 400 0 203 576
11/11/2014 300 0 0 574
11/12/2014 299 0 0 572
11/13/2014 296 0 0 571
11/14/2014 298 0 0 569
11/15/2014 299 0 0 568
11/16/2014 297 0 0 566
11/17/2014 301 0 0 564
11/18/2014 301 0 0 563
11/19/2014 301 0 0 561
11/20/2014 217 0 0 559
11/21/2014 421 179 0 560
11/22/2014 450 227 0 560
11/23/2014 450 231 0 561
11/24/2014 450 231 0 562
11/25/2014 456 231 0 562
11/26/2014 149 68 0 560
11/27/2014 0 0 0 557
11/28/2014 215 229 0 557
11/29/2014 397 275 0 557
11/30/2014 485 276 0 558
Total 10,958 1,947 2,559
Table 6.    Diversions to New York City water-supply system for report year ending November 30, 2014.

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]

Year Average daily consumption Annual consumption (Ggal)
City proper (Mgal/d) Outside communities (Mgal/d) Total (Mgal/d)
1950 953.3 29.1 982.4 358.6
1951 1,041.9 28.1 1,070.0 390.6
1952 1,087.0 32.7 1,119.7 409.8
1953 1,093.9 44.6 1,138.5 415.6
1954 1,063.4 46.3 1,109.7 405.0
1955 1,109.9 45.3 1,155.2 421.6
1956 1,111.3 48.9 1,160.2 424.6
1957 1,169.0 57.2 1,226.2 447.6
1958 1,152.9 49.6 1,202.5 438.9
1959 1,204.3 60.3 1,264.6 461.6
1960 1,199.4 58.9 1,258.3 460.5
1961 1,221.0 64.0 1,285.0 469.0
1962 1,207.6 68.8 1,276.4 465.9
1963 1,218.0 76.7 1,294.7 472.6
1964 1,189.2 79.4 1,268.6 464.3
1965 1,052.1 71.2 1,123.3 410.0
1966 1,044.9 73.2 1,118.1 408.1
1967 1,135.3 71.0 1,206.3 440.3
1968 1,242.0 78.2 1,320.2 483.2
1969 1,328.7 80.1 1,408.8 514.2
1970 1,400.3 90.4 1,490.7 544.1
1971 1,423.6 87.9 1,511.5 551.7
1972 1,412.4 83.0 1,495.4 547.3
1973 1,448.9 95.4 1,544.3 563.7
1974 1,441.8 96.3 1,538.1 561.4
1975 1,415.0 92.1 1,507.1 550.1
1976 1,435.0 95.8 1,530.8 560.3
1977 1,483.0 104.7 1,587.7 579.5
1978 1,479.4 103.0 1,582.4 577.6
1979 1,513.0 104.6 1,617.6 590.4
1980 1,506.3 110.1 1,616.3 591.6
1981 1,309.5 100.0 1,409.5 514.5
1982 1,383.0 104.8 1,487.8 543.1
1983 1,424.2 112.6 1,536.8 561.0
1984 1,465.2 113.9 1,579.1 578.0
1985 1,325.4 106.5 1,431.9 522.7
1986 1,351.1 115.2 1,466.3 535.2
1987 1,447.1 119.8 1,566.9 571.9
1988 1,484.3 125.6 1,609.9 589.1
1989 1,402.0 113.4 1,515.4 553.2
1990 1,424.4 122.4 1,546.8 564.6
1991 1,469.9 123.6 1,593.5 581.6
1992 1,368.7 113.9 1,482.6 542.6
1993 1,368.9 118.8 1,487.7 543.0
1994 1,357.8 119.2 1,477.0 539.1
1995 1,326.1 123.1 1,449.2 529.0
1996 1,283.5 120.2 1,403.7 512.4
1997 1,201.3 123.5 1,324.8 483.6
1998 1,220.0 124.7 1,344.7 490.8
1999 1,237.2 128.6 1,365.8 498.5
2000 1,240.4 124.9 1,365.3 499.7
2001 1,184.0 128.4 1,312.4 479.0
2002 1,135.6 121.1 1,256.7 458.7
2003 1,093.7 115.9 1,209.6 441.5
2004 1,099.6 117.5 1,217.1 445.5
2005 1,107.6 123.8 1,231.4 449.5
2006 1,069.2 116.8 1,186.0 432.9
2007 1,114.0 122.9 1,237.0 451.5
2008 1,082.9 114.8 1,197.7 438.4
2009 1,007.2 109.4 1,116.6 407.6
2010 1,039.0 119.0 1,158.0 422.7
2011 1,021.0 116.0 1,137.0 415.0
2012 1,009.1 110.2 1,119.3 409.7
2013 1,006.1 110.1 1,116.2 407.4
2014 996.0 109.6 1,105.6 403.5
Table 7.    Consumption of water by New York City, from 1950 to 2014.

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]

Day Dec. Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov.
1 69 88 96 97 85 160 84 96 97 e100 90 90
2 67 87 97 98