Geology topics

Research about Delaware, Maryland, New Jersey, New York, Pennsylvania

Source-linked reports with geographic coverage including Delaware, Maryland, New Jersey, New York, Pennsylvania.

12 recordsLinked to original sources

USGS2025

Regional high-frequency monitoring revealed chloride concentrations in exceedance of ecological benchmarks in urban streams across the Delaware River Basin, USA

Rising chloride concentrations pose critical risks to freshwater stream ecosystems in temperate regions like the Delaware River Basin (DRB), USA, where winter deicer applications ( i.e. , road salt) are common. Increasing chloride concentrations have been documented in the region, but the extent to which chloride exceeds regulatory benchmarks remains unclear because detection of exceedances requires continuous monitoring of chloride ( i.e. , hourly or daily). A network of 82 non-tidal continuous specific conductance (SC) monitoring sites, spanning varied land use and geological settings, was established across the DRB to address this research need. First, a cluster analysis was conducted to group sites based on their watershed characteristics. Next, regression models for sites and clusters were developed to predict chloride using SC as a proxy. Finally, daily mean and hourly mean chloride concentration predictions were made for a three-year period (2020–2022) at the 82 study sites and analyzed to determine where and when chloride exceeded federal regulatory benchmarks. Chloride exceedance events occurred at 35% of the sites, all of which had 5% impervious cover or greater. Seasonally elevated chloride also was predicted at sites with less than 5% impervious cover. Variability in chloride patterns likely was influenced by deicer material types, winter weather patterns, geological settings, and gaps in data coverage. This study demonstrated the value of SC as a proxy for predicting chloride concentrations and showed how SC-chloride regression relationships vary across settings. More broadly, this study highlighted the value of continuous water quality monitoring to assess effects of freshwater salinization at a regional scale.

Delaware, Maryland, New Jersey, New York, Pennsylv↗

USGS2024

Report of the River Master of the Delaware River for the period December 1, 2015 - November 30, 2016

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 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 63rd annual report of the River Master of the Delaware River. The report covers the 2016 River Master report year, which is the period from December 1, 2015, to November 30, 2016. During the report year, precipitation in the upper Delaware River Basin was 38.6 inches or 87 percent of the long-term average. Combined storage remained high (above 80 percent of combined capacity) for much of the year and did not decline below 80 percent of combined capacity until August 2016. The lowest combined storage was 106.406 billion gallons or 39 percent of combined capacity on November 28, 2016. Delaware River Basin Commission Resolution 2016–07 necessitated a basinwide drought watch on November 23, 2016. The drought watch continued through the remainder of the 2016 report year. Delaware River Master operations during the year were conducted as stipulated by the Decree and the Flexible Flow Management Program. New York City and New Jersey fully complied with the terms of the Decree and, during drought watch conditions, with the Delaware River Basin Commission Resolution 2016–07 terms. Diversions from the Delaware River Basin by New York City and New Jersey fully complied with the Decree. The 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 126 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 the 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 sites.

Delaware, Maryland, New Jersey, New York, Pennsylv↗

USGS2021

Prototyping a methodology for long-term (1680-2100) historical-to-future landscape modeling for the conterminous United States

Land system change has been identified as one of four major Earth system processes where change has passed a destabilizing threshold. A historical record of landscape change is required to understand the impacts change has had on human and natural systems, while scenarios of future landscape change are required to facilitate planning and mitigation efforts. A methodology for modeling long-term historical and future landscape change was applied in the Delaware River Basin of the United States. A parcel-based modeling framework was used to reconstruct historical landscapes back to 1680, parameterized with a variety of spatial and nonspatial historical datasets. Similarly, scenarios of future landscape change were modeled for multiple scenarios out to 2100. Results demonstrate the ability to represent historical land cover proportions and general patterns at broad spatial scales and model multiple potential future landscape trajectories. The resulting land cover collection provides consistent data from 1680 through 2100, at a 30-m spatial resolution, 10-year intervals, and high thematic resolution. The data are consistent with the spatial and thematic characteristics of widely used national-scale land cover datasets, facilitating use within existing land management and research workflows. The methodology demonstrated in the Delaware River Basin is extensible and scalable, with potential applications at national scales for the United States.

Delaware, Maryland, New Jersey, New York, Pennsylv↗

USGS2019

Report of the River Master of the Delaware River for the period December 1, 2009–November 30, 2010

A Decree of the Supreme Court of the United States, entered June 7, 1954, established the position of Delaware River Master within the U.S. Geological Survey. In addition, the Decree authorizes diversion of water from the Delaware River Basin and requires compensating releases from certain 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 will furnish reports to the Court, not less frequently than annually. This report is the 57th Annual Report of the River Master of the Delaware River. It covers the 2010 River Master report year, the period from December 1, 2009, to November 30, 2010. During the report year, precipitation in the upper Delaware River Basin was 49.38 inches or 112 percent of the long-term average. Combined storage in Pepacton, Cannonsville, and Neversink Reservoirs remained high much of the year and did not decline below 80 percent of combined capacity until September 2010. A lower basin drought warning was issued by the Delaware River Basin Commission on September 24, 2010. It automatically ended on October 31, 2010, when the reservoir contents rose above drought levels, due in large part to heavy rainfall during the last week of September. 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 New Jersey were in full compliance 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 81 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 made during the report year. The quality of water in the Delaware Estuary between Trenton, New Jersey, and Reedy Island Jetty, Delaware, was monitored at various locations. Data on water temperature, specific conductance, dissolved oxygen, and pH were collected continuously by electronic instruments at four sites.

Delaware, Maryland, New Jersey, New York, Pennsylv↗

USGS2018

Climate change science and modeling

This chapter provides a brief background on climate change science, climate simulation models, and models that project the impacts of changes in climate on tree species and ecosystems. Throughout the chapter, boxes list resources for more information on each topic. A more detailed scientific review of climate change science, trends, and modeling can be found in the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (IPCC 2014), and the Fourth National Climate Assessment (U.S. Global Climate Research Program [USGCRP] 2017).

Delaware, Maryland, New Jersey, New York, Pennsylv↗

USGS2015

User manuals for the Delaware River Basin Water Availability Tool for Environmental Resources (DRB–WATER) and associated WATER application utilities

The Water Availability Tool for Environmental Resources (WATER) is a decision support system (DSS) for the nontidal part of the Delaware River Basin (DRB) that provides a consistent and objective method of simulating streamflow under historical, forecasted, and managed conditions. WATER integrates geospatial sampling of landscape characteristics, including topographic and soil properties, with a regionally calibrated hillslope-hydrology model, an impervious-surface model, and hydroclimatic models that have been parameterized using three hydrologic response units—forested, agricultural, and developed land cover. It is this integration that enables the regional hydrologic-modeling approach used in WATER without requiring site-specific optimization or those stationary conditions inferred when using a statistical model. The DSS provides a “historical” database, ideal for simulating streamflow for 2001–11, in addition to land-cover forecasts that focus on 2030 and 2060. The WATER Application Utilities are provided with the DSS and apply change factors for precipitation, temperature, and potential evapotranspiration to a 1981–2011 climatic record provided with the DSS. These change factors were derived from a suite of general circulation models (GCMs) and representative concentration pathway (RCP) emission scenarios. These change factors are based on 25-year monthly averages (normals) that are centere on 2030 and 2060. The WATER Application Utilities also can be used to apply a 2010 snapshot of water use for the DRB; a factorial approach enables scenario testing of increased or decreased water use for each simulation. Finally, the WATER Application Utilities can be used to reformat streamflow time series for input to statistical or reservoir management software.

Delaware, Maryland, New Jersey, New York, Pennsylv↗

USGS2015

Summary of hydrologic modeling for the Delaware River Basin using the Water Availability Tool for Environmental Resources (WATER)

The Water Availability Tool for Environmental Resources (WATER) is a decision support system for the nontidal part of the Delaware River Basin that provides a consistent and objective method of simulating streamflow under historical, forecasted, and managed conditions. In order to quantify the uncertainty associated with these simulations, however, streamflow and the associated hydroclimatic variables of potential evapotranspiration, actual evapotranspiration, and snow accumulation and snowmelt must be simulated and compared to long-term, daily observations from sites. This report details model development and optimization, statistical evaluation of simulations for 57 basins ranging from 2 to 930 km 2 and 11.0 to 99.5 percent forested cover, and how this statistical evaluation of daily streamflow relates to simulating environmental changes and management decisions that are best examined at monthly time steps normalized over multiple decades. The decision support system provides a database of historical spatial and climatic data for simulating streamflow for 2001–11, in addition to land-cover and general circulation model forecasts that focus on 2030 and 2060. WATER integrates geospatial sampling of landscape characteristics, including topographic and soil properties, with a regionally calibrated hillslope-hydrology model, an impervious-surface model, and hydroclimatic models that were parameterized by using three hydrologic response units: forested, agricultural, and developed land cover. This integration enables the regional hydrologic modeling approach used in WATER without requiring site-specific optimization or those stationary conditions inferred when using a statistical model.

Delaware, Maryland, New Jersey, New York, Pennsylv↗

USGS2006

Report of the River Master of the Delaware River for the period December 1, 2001 - November 30, 2002

A Decree of the United States Supreme Court in 1954 established the position of Delaware River Master within the U.S. Geological Survey. In addition, the Decree authorizes diversions of water from the Delaware River Basin and requires compensating releases from certain 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 will furnish reports to the Court, not less frequently than annually. This report is the 49th Annual Report of the River Master of the Delaware River. It covers the 2002 River Master report year, that is, the period from December 1, 2001, to November 30, 2002. During the report year, precipitation in the upper Delaware River Basin was 2.73 in. greater than the long-term average. Combined storage in Pepacton, Cannonsville, and Neversink Reservoirs was at a record low level on December 1, 2001. Reservoir storage increased steadily from mid-winter until late June. Storage declined steadily from early July to mid-October then increased through the end of the year. Delaware River operations were conducted at reduced levels from December 1, 2001, to May 25, 2002, when drought emergency conditions prevailed, and as prescribed by the Decree from May 26, 2002, to November 30, 2002. Diversions from the Delaware River Basin by New York City and New Jersey were in compliance with the terms of the Decree or with the reduced limits in effect during drought emergency conditions. 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 101 days during the report year. Releases were made at experimental conservation rates-or rates designed to relieve thermal stress and protect the fishery and aquatic habitat in the tailwaters of the reservoirs-on all other days. During the report year, New York City and New Jersey complied fully with the terms of the Decree, and during drought emergency conditions, with the terms of the 'Interstate Water Management Recommendations of the Parties to the Decree' (DRBC Resolution 83-13), and directives and requests of the River Master. As part of a long-term program, the quality of water in the Delaware Estuary between Trenton, New Jersey, and Reedy Island Jetty, Delaware, was monitored at various locations. Data on water temperature, specific conductance, dissolved oxygen, and pH were collected by electronic instruments at four sites, and data on water temperature and specific conductance were collected at one site. In addition, selected water-quality data were collected at 3 sites on a monthly basis and at 19 sites on a semimonthly basis.

Delaware, Maryland, New Jersey, New York, Pennsylv↗

USGS2004

Pesticide compounds in streamwater in the Delaware River Basin, December 1998-August 2001

During 1998-2001, 533 samples of streamwater at 94 sites were collected in the Delaware River Basin in Pennsylvania, New Jersey, New York, and Delaware as part of the U.S. Geological Survey National Water-Quality Assessment Program. Of these samples, 531 samples were analyzed for dissolved concentrations of 47 pesticide compounds (43 pesticides and 4 pesticide degradation products); 70 samples were analyzed for an additional 6 pesticide degradation products. Of the 47 pesticide compounds analyzed for in 531 samples, 30 were detected. The most often detected compounds were atrazine (90.2 percent of samples), metolachlor (86.1 percent), deethylatrazine (82.5 percent), and simazine (78.9 percent). Atrazine, metolachlor, and simazine are pesticides; deethylatrazine is a degradation product of atrazine. Relations between concentrations of pesticides in samples from selected streamwater sites and characteristics of the subbasins draining to these sites were evaluated to determine whether agricultural uses or nonagricultural uses appeared to be the more important sources. Concentrations of atrazine, metolachlor, and pendimethalin appear to be attributable more to agricultural uses than to nonagricultural uses; concentrations of prometon, diazinon, chlorpyrifos, tebuthiuron, trifluralin, and carbaryl appear to be attributable more to nonagricultural uses. In general, pesticide concentrations during the growing season (April-October) were greater than those during the nongrowing season (November-March). For atrazine, metolachlor, and acetochlor, the greatest concentrations generally occurred during May, June, and July. Concentrations of pesticide compounds rarely (in only 7 out of 531 samples) exceeded drinking-water standards or guidelines, indicating that, when considered individually, these compounds present little hazard to the health of the public through consumption of the streamwater. The combined effects of more than one pesticide compound in streamwater were not considered. Diazinon appeared to be the pesticide compound most likely to adversely affect aquatic life in the streams of the Delaware River Basin; concentrations of diazinon exceeded guidelines (designed to protect aquatic life) in 19 samples, the most of any pesticide compound. Concentrations of as many as 5 compounds exceeded guidelines in 29 of 531 samples.

Delaware, Maryland, New Jersey, New York, Pennsylv↗

USGS1999

Delaware River Basin

During the past 25 years, industry and government have made large financial investments in manufacturing, processing, and wastewater-treatment facilities to reduce the amount of contaminants being discharged. Although these investments have led to improved water quality across the Nation, concerns about the effects of nutrients, toxins, and pathogens on human health and that of ecological communities remain. To address the need for consistent and scientifically sound information for managing the Nation's water resources, the U.S. Geological Survey began the National Water-Quality Assessment (NAWQA) program in 1991. This program is unique in that it integrates surface- and ground-water-quality monitoring with the study of aquatic ecosystems. The goals of the NAWQA program are to (1) describe current water-quality conditions for a large part of the Nation's freshwater streams and aquifers (water-bearing sediments and rocks), (2) describe how water quality is changing over time, and (3) increase our understanding of the natural and human factors that affect water quality (Leahy and others, 1990, Gilliom and others, 1995). Assessing the quality of water in every location of the Nation would not be practical. Therefore, NAWQA investigations are conducted within 59 selected areas called study units (fig. 1). These study units encompass important river and aquifer systems in the United States and represent the diverse geographic, waterresource, land-use, and water-use characteristics of the Nation. The Delaware River Basin is one of 15 study units in which work began in 1996. Water-quality sampling in the study unit will begin in 1999. This fact sheet provides a brief overview of the NAWQA program, describes the Delaware River Basin study unit, identifies the major water-quality issues in the basin, and documents the plan of study that will be followed during the study-unit investigation.

Delaware, Maryland, New Jersey, New York, Pennsylv↗

USGS1981

Flood peaks and discharge summaries in the Delaware River basin

Streamflow data from 299 continuous and crest-stage sites in the Delaware River basin are summarized in this report. The location, drainage area, period of record, type of gage, and average discharge for each gaging site are given. Also included are tables of annual peaks and peaks above base, annual and monthly means, and annual and monthly runoff.

Delaware, Maryland, New Jersey, New York, Pennsylv↗

USGS1967

Delaware River basin - water data stations, 1967

This report presents information on station-type activities for acquiring surface-water, ground-water, and quality of water data in the Delaware River basin. The information was collected in 1966 through field offices of the Water Resources Division, U.S. Geological Survey as part of a pilot study for the Office of Water Data Coordination. The cooperation and assistance of various Federal, state, and local agencies (table 1) whose activities are listed is acknowledged with appreciation. No attempt was made during the pilot study to inventory data collected by private industries, but information was available for a number of them. This information is included in the report as an example of the extensive data-collection effort by private groups in the Delaware River basin.

Delaware, Maryland, New Jersey, New York, Pennsylv↗