What effect does heavy rainfall have on the Bay?

Welcome to the latest installment of the BayBlog Question of the Week! Each week, we take a question submitted on the Chesapeake Bay Program website or a frequently asked question and answer it here for all to read.

This week’s question is all about the wet weather we’ve had in the region lately: “What effect does heavy rainfall have on the Bay?”

The amount of rainfall the Chesapeake Bay region receives affects the amount of water that flows into the Bay from its rivers. This is called river flow. When we get more rain, it increases the amount of nutrient and sediment pollution that gets into local streams and rivers, and eventually the Bay.

When it rains, stormwater runs off lawns, farms, streets and parking lots, picking up pollution and carrying it into the nearest storm drain or waterway. A lot of rain can also erode stream banks, which causes more sediment to make its way to the Bay. Excess nutrients and sediments are harmful because they block sunlight from reaching bay grasses. Excess nutrients also fuel the growth of algae blooms that can lead to low oxygen levels.

But heavy rainfall can also carry with it much more visible signs of pollution: namely, trash.

The Baltimore Sun’s B’More Green Blog posted some compelling photos this morning, taken at the Inner Harbor in Baltimore by the National Aquarium. It seems that not only did all the rain likely carry a lot of nutrients and sediment into the Bay, it also "trashed" the harbor.

The EPA has officially dubbed Baltimore’s Inner Harbor as “impaired” by trash. The Anacostia River watershed in Washington, D.C., has a similar, if not more severe, issue. The Anacostia recently became the first interstate river to have a Clean Water Act “trash pollution diet” imposed on it.

If there's one good thing about all this rain, it's that seeing all the trash it carries into our local waterways reminds us to try and minimize the trash we use in our day-to-day routines. After all, do you want to be swimming with a bunch of old coffee cups -- or eating seafood that has been doing the same?

Do you have a question about the Chesapeake Bay? Ask us and we might choose your question for the next Question of the Week! You can also ask us a question via Twitter by sending a reply to @chesbayprogram! Be sure to follow us there for all the latest in Bay news and events.