Friday, July 29, 2016


A Havre de Grace Green Team Blogpost
by Karl Ford - Education Initiative Chairperson

What is the definition of stormwater?  Why should we care about stormwater management? Well, stormwater is quite simply rainwater and rainwater ends up in our lakes and reservoirs…..and ultimately our homes.

When it rains, the rainwater will interact with four types of surface areas found in our environment; the air before it hits the ground, permeable ground surfaces, impermeable ground surfaces, or bodies of water. Most of us don’t think of the air around us as a surface that interacts with rainwater and thus has an effect on our water quality. However, air pollutants can be picked up by rainwater and enter the environment.  Once the rain reaches the ground it interacts with three additional surfaces. Impermeable surfaces, which includes buildings, parking lots, roadways, as well as natural rock formations, through which water cannot penetrate. Permeable surfaces, which includes natural areas like grasslands, forests, and bare soil.  Increasingly, due to efforts to protect water quality, this also includes man-made permeable surfaces. Lastly, rivers, lakes, creeks, streams, man-made reservoirs, and of course the oceans make up the final types of surface.   

The effect of rainwater’s interaction with each surface is dependent on the characteristics of that surface.  Erosion caused by rainwater run-off can be controlled by the environment’s surface features, both natural and man-made. Vegetation acts as a natural soil stabilizer, holding the soil in place, as well as controlling the velocity and volume of the water runoff. Vegetated areas, such as

grasslands and forests, also act as natural filters, retaining debris and particulates in the soil and not allowing them to enter our water bodies. Impermeable surfaces concentrate the volume and the velocity of rainwater run-off entering the environment. Unfortunately, impermeable surfaces also concentrate the contaminants in the stormwater run-off.  These contaminants are then deposited in our creeks, streams, rivers and the bay. Stormwater management programs exist to minimize soil erosion and stormwater contamination by mitigating increases in water volume and velocity. The public can and should play a vital role in helping to manage overall water quality by monitoring their local stormwater systems.

As we enjoy the warm weather and the associated activities that go along with the pleasures of summertime, we should pay special attention to what goes into our streets, gutters, and storm drains. “Only Rain in the Drain” is a good phrase to keep in mind. Make it a point to limit or eliminate any chemicals, petroleum products, trash, debris, and soil from entering the stormwater system. You can contact the Havre de Grace Green Team, city or county government, and other local environmental groups, for information on best practices to protect our precious water resources.