April showers never materialized in the Bay watershed, as monitoring by the U.S. Geological Survey showed river flows into the Chesapeake were the lowest on record for the month.
USGS monitoring showed that freshwater flows from the Chesapeake Bay’s major tributaries averaged 56,100 cubic feet per second in April. That’s only about 40 percent of the 144,000 cfs average for the month during 76 years of USGS monitoring. The previous low was 59,000 cfs in 1995.
Dry conditions were widespread in the Bay watershed during April. Joel Blomquist, a USGS hydrologist, said flows from the Susquehanna River, the Chesapeake’s largest tributary, were the 75th lowest out of 76 years of monitoring; flows from the Potomac, the second largest tributary, ranked 73rd during the same time period, and flows from the James, the third largest tributary, ranked 59th.
Flows were also lower than normal in February and March, although not record-setting.
March flows were 115,000 cfs, compared with the long term average of 149,000 cfs, while February flows were 77,000 cfs, compared with the long-term average of 102,000 cfs, according to USGS figures.
Normally, low spring flows translate into improved summertime water quality in the Chesapeake because the low flows wash in fewer nutrients from the watershed.
What will happen this year is less certain though, as scientists are concerned that an excess of nutrients may be left over from Hurricane Irene and Tropical Storm Lee, which flushed huge amounts of water and nutrients into the Chesapeake late last summer.