USGS scientists said that rivers and streams carried a combined average flow of 87.5 billion gallons of water per day (bgd) into the Bay during the past year, about 1.7 times the long-term normal. Previous record high was 85.1 bgd in 1972, the year of Hurricane Agnes.
The high flows also carried increased amounts of sediment, nutrients, and other chemicals that affected the water quality and living resources of the Bay. The environmental effects could have been much worse, however, according to preliminary information collected by the agencies involved in the cooperative Chesapeake Bay Program.
"The repeated high waters and floods of 1996 caused obvious and serious economic damage throughout the upstream Chesapeake basin. Less well understood are the environmental effects of those record inflows to the Bay itself," according to Scott Phillips, coordinator of the USGS Chesapeake Bay effort, Towson, Md.
"Although the record freshwater inflows damaged and caused localized losses to vegetation and oyster beds, the total impact on the Bay ecosystem probably did not match the damage from the previous record flow year of 1972," Phillips said.
"Two primary factors -- the timing of the large storms and the success of management actions to reduce nutrients entering the Bay -- lessened the potential effects of the high flows," the USGS spokesman said.
These favorable factors include:
Chesapeake Bay Program agencies reported that high flows in 1996 affected the Bay in several ways: