Downspout Disconnection
Pollution Prevention with a Payback

A simple yet effective way for property owners to help manage stormwater is by disconnecting their downspouts. Appropriately disconnecting downspouts benefits property owners as well as the environment. Allowing stormwater to naturally soak into the soil keeps it from entering our combined sewer system and decreases the frequency of Combined Sewer Overflows (CSOs) which dump chemical pollution and raw sewage into the Anacostia, Potomac and Rock Creek waterways.

In addition to contributing to the greater good, property owners also benefit their wallets by disconnecting their downspouts. Any water that is diverted from the sewer system (whether stored for later use or directed elsewhere) can be viewed as free water to use in watering the lawn or garden or washing the car.

You might not think that much water would be available to a property owner even during a large storm, but one inch of rain on 1,000 square feet of rooftop creates over 600 gallons of stormwater. Also, the less likely the sewer system is to overflow, the less likely it is for basements to flood.

There are basically two options for the management of stormwater when the downspout is disconnected: storage or diversion. If diversion is selected it is best to divert the stormwater to where it will do the most good or infiltrate the soil most efficiently, such as a rain garden, a lawn, or some other form of bioretention. At the very least, it should not cause any problems (icing over a right-of-way or flooding the neighbor’s yard). A rain barrel is a good way to store stormwater as it leaves the downspout. Rain barrels may be purchased or easily and inexpensively constructed. Links >>