Heavy rains and melting snow are taking a toll on the Chesapeake Bay.

Officials with the Maryland Department of Natural Resources say rain and snow runoff are bringing a flood of nutrients and sediments into the bay, threatening water quality. The heavy spring runoff has led to record low water clarity in many areas.

More wet weather could mean more polluted runoff that can spawn oxygen-robbing algal blooms and lead to fewer underwater grasses, which are a key habitat for many species.

The DNR says the flow over the Conowingo Dam on March 12 was the highest since Tropical Storm Ivan in 2004, and more than six times the average for the month.