Springtime Heavy Rainfall Could Be Detrimental To Bay
BALTIMORE (WJZ)—We've seen our share of rain this March. Now scientists are concerned we could see more rain than is good for the Bay.
Alex DeMetrick reports spring rainfall puts the dead zones of summer in motion.
Heavy rain and snow melt earlier this month threatened flooding for a few days along the Susquehanna. But what that runoff carries now threatens much of the Bay.
"The spring rains contribute nitrogen, phosphorous and sediment into the Bay, and our concern is we have excess amounts of nitrogen, phosphorous and sediment," said Bruce Michael, DNR Resource Assessment Service.
Water flowed at 485-cubic feet a second out of the Conowingo Dam—way above standard spring releases. Amounts were up for other waterways throughout the Chesapeake.
Those who monitor Maryland's streams worry about too much rain falling over too little time.
"If you have a nice gentle rain, it sort of soaks through the ground and is able to filter before it enters the stream. But when you have a heavy downpour, it throws everything into the stream," said Christine King, DNR biologist.
Nitrogen and phosphorous will now start feeding algae, which will bloom into oxygen-starved dead zones this summer. Millions of tons of sediment will create underwater clouds, which threaten critical habitat.
"Our underwater grasses are just beginning to grow. As sediment clouds the water, it reduces the amount of light available to those plants at the bottom," Michael said.
The last time this much runoff hit the bay was in 2004. That's when the remnants of Hurricane Ivan turned the water brown, killing grass beds and crabs. But that was the end of summer and spring is the worst time for heavy rains.
Maryland's efforts to improve buffers along streams and advanced sewage treatment have improved water quality, although heavy rains can still overwhelm waterways.
