That was the lowest recorded for May since USGS began monitoring flows into the Bay in 1951. Government officials have been urging people to conserve water throughout much of the Bay states. Pennsylvania issued a 47-county drought warning that included most of its portion of the watershed. Ironically, the low flow conditions which have persisted since last summer followed a record high flow into the Chesapeake during the first six months of last year. The El Nino that proceeded La Nina was credited with contributing to the those flows, the highest for any six-month period on record.
Water flows have a dramatic affect on the Bay.
High flows typically contribute to poor water quality. They flush huge amounts of nutrients into the Bay, spurring algae blooms which block sunlight from reaching important underwater grasses that provide food and shelter for fish, shellfish and waterfowl. When the algae die, they sink to the bottom and decompose in a process that depletes the water of oxygen. Strong flows also wash more sediment into the Bay, which also clouds the water. Last year's high flows are thought to have contributed to a 10 percent decline in Bay grass acreage in 1998, measured from the previous year.