Summer Rain and The Chesapeake Bay

I think we can all agree that water has been dumping into our local waterways and the Chesapeake Bay at an alarming rate this summer. Communities throughout the watershed have seen it with their own eyes, with major flooding events causing destruction of property and even loss of life. Maryland alone has experienced the rainiest and wettest year on record in more than a century, with 43 inches of rain falling in July through August. That is the most it’s rained since 1889. One begins to wonder just how much the precipitation has impacted the Chesapeake Bay.

 Photo by Chesapeake Bay Program

Photo by Chesapeake Bay Program

One of the biggest impacts has been on the Susquehanna River. The Susquehanna, which starts in Cooperstown, New York, flows through Pennsylvania, and reaches the Bay in Havre De Grace, Maryland, is the Chesapeake’s largest tributary. The Susquehanna provides half of the Bay’s fresh water and this year river levels have risen to record highs, which in turn has caused major flooding. So much so that Exelon Power, the company that superintends Conowingo Dam and sits on the Susquehanna River, opened the dam’s floodgates multiple times to relieve the pressure building behind the dam. As a result, the dam unleashed nutrient rich sediment and pollution. In the past, the Conowingo Dam was able to hold large quantities of sediment, but the reservoir has reached its capacity, so nutrient and sediment pollution is now making its way over the dam. According to Exelon, the recent amount of debris has been the largest in 20 years. In a statement, Exelon said to have removed 1,800 tons of trash from behind the dam and are still cleaning. When the dam is opened, pollution flows freely down into the Chesapeake, carrying everything from garbage to tree branches and trunks.

In addition to nutrient and trash pollution, the increased water is causing an issue many may not have considered. As an estuary, the Chesapeake receives its fresh water from its rivers and salt water from the Atlantic Ocean. Due to the all-time-high fresh water flow coming in from its tributaries, the Bay has seen a decrease in its salinity. This can pose a threat to plant and animal life, like oysters and blue crabs, which can only tolerate or thrive in certain water conditions.

 Photo by Matthew Beziat

Photo by Matthew Beziat

Huge rainstorms have proven time and time again how devastating it can be for organisms on land and under water. With heavy rainfall comes not only stormwater runoff but agriculture runoff as well; the single largest source of nutrient and sediment pollution entering the Bay. The excess of nutrients, such as nitrogen and phosphorus, that enter the Bay power the growth of algae blooms that block sunlight from reaching the underwater grasses. It robs the water of oxygen that plants and animals are dependent on to survive. The Bay’s underwater vegetation, where many blue crabs, fish and shellfish reside, is an indicator in determining the health of the Chesapeake Bay. Healthy underwater grasses provide food and habitat for animals, reduces shoreline erosion and improves overall water quality by slowing down the current and filtering sediment.

It will obviously take time for scientists to measure the full effects the rain has truly had on the Bay. In the meantime, let’s do all that we can to prevent any further damage from stormwater runoff by installing rain gardens, rain barrels, forest buffers, and implementing proper conservation practices. If you see trash, pick it up. It will end up somewhere it shouldn’t.  We can’t control the weather, but we can control our own actions.

Learn more about storm water runoff here.

Taylor Montford is the communications intern for the Choose Clean Water Coalition.