in the upper meter of sediment at 

 stations from the mouth of the Sus- 

 quehanna River to the Virginia Capes 

 on a seasonal basis. These data per- 

 mit calculations of the benthic flux 

 of nutrients and trace metals from 

 the bottom sediment to the estuarine 

 waters. At the same locations, box 

 cores have been collected for benthic 

 infaunal investigations. The inte- 

 gration of the physical and chemical 

 characteristics of the sediment with 

 the benthic infaunal biota will pro- 

 vide better understanding of the role 

 of bottom sediments in estuarine 

 processes . 



EXISTING CONDITIONS IN BAY 



BAYWIDE SURVEY 



The hydrodynamic field survey 

 was designed to provide a data set 

 with which to construct and verify a 

 numerical model of the Chesapeake 

 Bay. The aim was to provide a 

 one-month measurement series of the 

 circulation and driving forces of the 

 Chesapeake Bay System to include: 

 temperature, salinity, current, tide 

 stage, freshwater inflow and meteo- 

 rological measurements. 



Seventy current meters were 

 moored throughout the bay during the 

 month of July. Nearly half of the 

 current meters had salinity and tem- 

 perature recording capability (pri- 

 mary moorings). The mouth of Chesa- 

 peake Bay between the Virginia Capes 

 was the most heavily instrumented, in 

 order to obtain an estimate of the 

 inflow and outflow of the estuary. 

 Instruments were also concentrated on 

 the Cape Charles City - Mobjack Bay 

 transect because of the unique cir- 

 culation features which have been 

 demonstrated in this area (Figure 3) . 

 The Smith Point - Tangier Sound 

 section was designed to measure the 



outflow from the Potomac as well as 

 the interaction of the Tangier Sound 

 water masses with the bay proper. 

 Single moorings were deployed off 

 Chesapeake Beach, at the Bay Bridge 

 and north of Pooles Island in order 

 to coordinate with the intensive in- 

 formational base that already exists 

 from previous Chesapeake Bay studies. 

 Additional primary moorings were 

 provided by the United States Geolog- 

 ical Survey in the Potomac River and 

 by the Maryland Water Resources 

 Administration near the mouths of the 

 Chester and Patuxent rivers. 



Two wind speed and direction 

 recorders were placed on the lower 

 eastern shore of the Chesapeake Bay 

 to fill in the sparse distribution of 

 National Weather Service meteorologi- 

 cal stations that now exist for the 

 bay area. In addition, two tide sta- 

 tions were established on the lower 

 eastern shore, because this area was 

 not covered adequately with tide 

 gages. 



A comprehensive set of nutrient 

 data for Chesapeake Bay and its trib- 

 utaries was collected during the pe- 

 riod of July 9-16, 1980. This data 

 set will characterize boundary condi- 

 tions for the bay (bay mouth and 

 tributary mouths) and will also in- 

 clude several transects across the 

 bay. Water movement data, as well as 

 temperature, salinity, chlorophyll a, 

 dissolved oxygen, suspended sediment 

 and nutrients (particulate, dissolved 

 and total nitrogen and phosphorus 

 silicate, ammonia, nitrite, nitrate, 

 organic forms of nitrogen) were col- 

 lected at thirteen bay transects for 

 the purpose of mass balance and mod- 

 el verification. Sampling at bay 

 transects was performed twice a day 

 at each depth where a current meter 

 was recording water movement. Also, 

 during the eight-day, July field 

 study, sampling was conducted at 

 three-hour intervals for thirty-six 



193 



