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Richard A. Cartwright

Publications and source records attributed to Richard A. Cartwright.

6 recordsLinked to original sources
USGS2019

Estimating sediment flux to Jamaica Bay, New York

Tidal wetland loss in Jamaica Bay, New York, is well documented. Maintaining wetlands is important from an environmental and ecological perspective and because wetlands buffer coastal communities from storm damage. An estimate of suspended-sediment flux through Rockaway Inlet is needed to improve understanding of sediment dynamics in Jamaica Bay and could be used in salt marsh restoration efforts. To estimate sediment flux, an index-velocity station and turbidity sensor were installed and operated in Rockaway Inlet near the mouth of Jamaica Bay from November 2014 to December 2016 and point and cross-sectional suspended-sediment samples were collected and analyzed. Index-velocity data coupled with cross-sectional acoustic Doppler current profiler measurements were used to develop an index-velocity rating. A simple linear regression rating with a strong coefficient of determination (R 2 of 0.981) was developed. Discharge was computed from the stage-area and index-velocity relations, and a low-pass Godin filter was used to remove the tidal aliasing. A second simple linear regression (R 2 of 0.75) between fixed-point suspended-sediment concentration (SSC) samples and turbidity allowed for the calculation of SSC through Rockaway Inlet, and then sediment flux was found by multiplying SSC and discharge for continuous (6-minute) data. Turbidity values were low in the near-ocean conditions at Rockaway Inlet, with daily means ranging from 0.6 to 8.2 formazin nephelometric units during the period of November 2014 through December 2016. During this time, computed daily mean suspended-sediment concentrations ranged from 3 to 13 milligrams per liter. High sediment loads generally occurred during incoming tides, during both storm and nonstorm conditions, suggesting a net inward sediment flux into Jamaica Bay. The fate of sediment after it enters Jamaica Bay was not investigated. Trends in sediment flux during major storms could not be evaluated because no major storms occurred during this investigation.

New York↗
USGS2004

Occurrence of arsenic in ground water of Suffolk County, New York, 1997-2002

Water-quality data from public and private drinking-water supply wells that were sampled from October 1997 through March 2001 in Suffolk County, New York were evaluated to define the occurrence and concentrations of arsenic throughout the county. The data bases of the Suffolk County Water Authority (SCWA) and the Suffolk County Department of Health Services (SCDHS) included 14 wells at which arsenic concentrations approached or exceeded the 2002 U.S. Environmental Protection Agency (USEPA) drinking-water guideline of 10 micrograms per liter (µg/L). As a followup, 19 wells were sampled from June through August 2002; 7 were wells previously reported to have had high arsenic concentrations; 7 were near other wells reported to have high concentrations, and the remaining 5 were in areas where detectable concentrations of arsenic were suspected. Arsenic concentrations near 10 µg/L were detected at only 2 of the 19 wells sampled; arsenic concentrations in samples from the remaining 17 wells were reported as less than the USGS Central Laboratory reporting limits of 2 µg/L or 4 µg/L. The elevated concentrations previously reported (1997 through 2001) for at least three of the wells were due to incompletely flushed carbon filters in the supply-well system or were typographical errors. A decrease in arsenic concentration was indicated at six of the seven resampled wells; no reasons are apparent. Arsenic concentrations in ground water that exceed drinking-water guidelines were found only at one site. On the basis of limited sampling data available for this study, the concentrations of arsenic above drinking-water standards (10 µg/L) do not appear to indicate a countywide problem with regards to arsenic concentrations in ground water.

New York↗
USGS2002

History and hydrologic effects of ground-water use in Kings, Queens, and western Nassau Counties, Long Island, New York, 1800's through 1997

Ground-water withdrawals from the aquifers underlying Kings and Queens Counties varied temporally and spatially during the 20th century and caused extreme changes in water levels. The resultant lowering of water levels during periods of heavy pumping caused saltwater intrusion in nearshore areas and the migration of contaminants from land surface into deep aquifers. The recovery of water levels in response to countywide curtailment of pumping has resulted in the flooding of underground structures. Combined withdrawals for public and industrial supply in Kings and Queens Counties were greatest during the 1930's--about 130 million gallons per day. During this period, a large cone of depression developed in the water table in Kings County; within this depression, water levels were about 45 feet lower than in 1903. All pumping for public supply was halted in Kings County in 1947, and in Jamaica (in Queens County) in 1974. Water levels in Kings County had recovered by 1974 and have remained similar to those of 1903 since then, except for minor localized drawdowns due to industrial-supply or dewatering withdrawals. A large cone of depression that had formed in southeastern Queens County before 1974 has now (1997) disappeared. The estimated combined withdrawal for public supply and industrial supply in Kings and Queens Counties in 1996 was only about 50 million gallons per day. The water-level recoveries in the water-table and confined aquifers generally have resulted in the dilution and dispersion of residual salty and nitrate-contaminated ground water. The majority of recently sampled wells indicate stable or decreasing chloride and nitrate concentrations in all aquifers since 1983. Organic contaminants remain in ground water in Kings, Queens, and Nassau Counties, however; the most commonly detected compounds in 1992-96 were tetrachloroethene, trichloroethene, chloroform, and total trihalomethanes. Water samples from monitoring wells in Kings County indicate a greater number of occurrences of these compounds in the upper glacial aquifer than in the Jameco-Magothy aquifer, whereas samples from public-supply wells in Queens County indicated a greater number of occurrences in the Jameco- Magothy aquifer than in the upper glacial aquifer. This distribution suggests that organic contaminants were not drawn into the deeper aquifers in Kings County before 1947, when their use was limited and deep withdrawals were greatest, and (or) that the longer period of waterlevel recovery in Kings County than in Queens has allowed greater degradation, dilution, and dispersion of any organic contaminants that might have entered the deep aquifers before the cessation of pumping in 1947.

New York↗