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Marc A. Sylvester

Publications and source records attributed to Marc A. Sylvester.

6 recordsLinked to original sources
USGS2014

Chapter A7. Section 7.1. Fecal indicator bacteria

Fecal indicator bacteria are used to assess the microbiological quality of water because, although not typically disease causing, they are correlated with the presence of several waterborne disease-causing organisms. The concentration of indicator bacteria is a measure of water safety for body-contact recreation or for consumption. This report provides information on the equipment, sampling protocols, and identification, enumeration, and calculation procedures that are in standard use by U.S. Geological Survey (USGS) personnel for the collection of data on fecal indicator bacteria. Each chapter of the National Field Manual is published separately and revised periodically. Newly published and revised chapters will be announced on the USGS Home Page on the World Wide Web under 'New Publications of the U.S. Geological Survey.'

Techniques of Water-Resources Investigations↗
USGS1991

Effects of drainage on water, sediment and biota

The U.S. Department of the Interior started a program in 1985 to identify effects of irrigation-induced trace constituents in water, bottom sediment and biota. The program was developed in response to concerns that contamination similar to that found in 1983 at Kesterson Reservoir in California might exist elsewhere. Studies are complete or underway for 26 sites in 15 western States. Selenium is the trace constituent most often found at elevated concentrations in all media. Maximum selenium concentrations in fish from 9 of 20 areas exceeded the threshold concentration for adverse reproductive effects. Maximum selenium concentrations in bird livers from 11 areas exceeded the level at which embryonic deformities are likely; deformed birds were observed in 5 areas. Trace constituent problems may be anticipated if geologic sources such as marine shales occur in an irrigation project area. The potential for problems is increased if closed basins or sinks are present.

Conference Paper↗
USGS1988

Preliminary results of the Department of the Interior's irrigation drainage studies

The Department of the Interior, in 1986, began irrigation drainage studies in nine areas in seven Western states to determine whether irrigation drainage has caused or has the potential to cause harmful effects on human health, fish, and wildlife, or might reduce the suitability of water for beneficial uses. Results of the seven studies completed in 1987 are presented and are compared to baselines, standards, criteria, and other guidelines helpful for assessing the potential of observed constituent concentrations in water, bottom sediment, and biota to result in physiological harm to fish, wildlife, or humans. Selenium is the constituent most commonly found at elevated concentrations in water, bottom sediment, and biota in the study areas. Additional study results are discussed.

Conference Paper↗
USGS1978

Relation of urban land-use and land-surface characteristics to quantity and quality of storm runoff in two basins in California

Two basins (Castro Valley Creek, in Alameda County, and Strong Ranch Slough, in Sacramento County) in the San Francisco Bay and Sacramento-San Joaquin Delta region (Bay-Delta region) were sampled intensively (3-15 minute intervals) during three storms between October 1974 and April 1975. Both basins are primarily residential, but the Strong Ranch Slough basin is almost entirely urbanized and nearly flat, while the Castro Valley Creek basin possesses some rural areas and slopes greater than 70 percent in the headwaters. Water discharge and concentrations of suspended solids, chemical oxygen demand, 5-day biochemical oxygen demand, nitrite and nitrate, total Kjeldahl nitrogen, total orthophosphorus, and settleable matter were usually greater at the Castro Valley Creek basin than at the Strong Ranch Slough basin. Concentrations of these constituents and water discharge changed more rapidly at the Castro Valley Creek basin than at the Strong Ranch Slough basin. Of the four subbasins sampled (two in each basin), constituent concentrations in runoff from a residential subbasin were usually greatest. Quantity and quality of runoff were related to environmental characteristics such as slope, perviousness, residential development and maintenance, and channel conditions. Greater water discharge and concentrations of constituents in the Castro Valley Creek basin seem to be partly due to steeper slopes, less perviousness, and smaller residential lot sizes than are in the Strong Ranch Slough basin. Erosion of steep slopes disturbed by grazing and residential development, poorly maintained dwellings and lots, and a mostly earthen drainage channel in the Castro Valley Creek basin are probably responsible for the greater concentrations of suspended solids and settleable matter in runoff from this basin. In both basins, the highest observed concentrations of suspended solids, chemical oxygen demand, 5-day biochemical oxygen demand, settleable matter, total Kjeldahl nitrogen, and total orthophosphorus were observed at or near peak water discharges. Flow-weighted and arithmetic-mean concentrations of suspended solids in Castro Valley Creek exceed the arithmetic-mean concentration of suspended solids in medium-strength untreated sewage. These results indicate that control of urban storm runoff in the Bay-Delta region may be desirable to protect receiving water.

Water Supply Paper↗
USGS1977

Relation of urban land-use and land-surface characteristics to quantity and quality of storm runoff in two basins in California

Two basins (Castro Valley Creek, in Alameda County, and Strong Ranch Slough, in Sacramento County) in the San Francisco Bay and Sacramento San Joaquin Delta region (Bay-Delta region) were sampled intensively (3-15 minute intervals during three storms between October 1974 and April 1975. Both basins are primarily residential, but the Strong Ranch Slough basin is almost entirely urbanized and nearly flat, while the Castro Valley Creek basin possesses some rural areas and slopes greater than 70 percent in the headwaters. Water discharge and concentrations. of suspended solids, chemical oxygen demand, 5-day biochemical oxygen demand, nitrite and nitrate, total Kjeldahl nitrogen, total orthophosphorus, and settleable matter were usually greater at Castro Valley Creek basin than at the Strong Ranch Slough basin. Concentrations of these constituents and the water discharge changed more rapidly at the Castro Valley Creek basin than at the Strong Ranch Slough basin. Of the four subbasins sampled (two in each basin), constituent concentrations in runoff from a residential subbasin were usually greatest. Quantity and quality of runoff were related to environmental characteristics such as slope, perviousness, residential development and maintenance, and channel conditions. Greater water discharge and concentrations of constituents in the Castro Valley Creek basin seem to be partly due to steeper slopes, less perviousness, and smaller residential lot sizes than are in the Strong Ranch Slough basin. Erosion of steep slopes disturbed by grazing and residential development, poorly maintained dwellings and lots, and a mostly earthen drainage channel in the Castro Valley Creek basin are probably responsible for the greater concentrations of suspended solids and settleable matter in runoff from this basin.

California↗