USGS measures water quality at approximately one-third of its 

 stream mouth gaging stations. These measurements provide 

 synoptic data on selected chemical and physical variables and allow 

 the calculation of mass balances and the evaluation of pollutant 

 transfer from upstream into the Great Lakes and oceans. 



The USGS San Francisco Bay study illustrates application of the 

 stream, chemical, and sediment discharge data to seasonal variation 

 of chemical and physical conditions within this estuarine system. 

 Here, stream discharge bears a direct relation to and exerts 

 significant control over the residence time of water within the Bay. 

 The estuarine system is flushed most effectively during high-flow 

 periods when it produces a strong density-driven circulation. The 

 northern parts of the Bay enjoy normal estuarine circulation with 

 high-salinity water moving upstream along the floor beneath lower 

 salinity water that flows to the Pacific. The.southern part of the Bay, 

 with little fresh water inflow, undergoes reversals in nontidal 

 circulation. 



Mercury, lead, and copper concentrations in the sediments of San 

 Francisco Bay relate not only to geologic and hydrodynamic factors 

 but also to industrial development within the Bay region. Total 

 calculated volumes of selected elements within the sediments, high 

 local concentrations, and a large range of measured values are all 

 greater than would be expected in a natural estuarine system. Initial 

 stages of understanding the complex interacting systems in the Bay 

 have now been achieved, and predictive computer modeling is to be 

 developed for comparison with continuing field measurements. 



Through contracts and grants, largely to academic institutions, 

 DOI's Office of Water Resources Research supported 32 projects in 

 FY '73, and 29 projects in FY '74 that emphasize collection of basic 

 information relating to the source, fate, and effects of marine 

 pollutants and to pollution control. The projects included the effects 

 of pollutants on development and physiology of selected marine 

 larvae, a study of the transport of chlorinated hydrocarbons in 

 sediments of bays, the role of sea grasses and benthic algae in the 

 geochemistry of trace metals in estuaries, and phosphorus cycling 

 and storage by algae in bays as related to eutrophication. Another 

 continuing study deals with devising ways for collecting, packaging, 

 analyzing, and presenting to decisionmakers hydrologic, biologic, 

 socioeconomic and institutional information and methods whereby 

 fragile coastal ecosystems can be developed without undue 

 degradation. Similar studies are being supported by the National 

 Science Foundation (NSF) and NOAA. 



DOI Bureau of Land Management is funding environmental 

 studies in preparation for expanded OCS lease sales. Several studies 

 have recently been completed in the Eastern Gulf of Mexico and off 

 the California coasts. 



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