JeffCo H2O: What’s the Roof Got To Do with It?


What’s the Roof Got to Do with


Actually, a lot!  During a one inch rain, a 1,000 square foot roof has about 600 gallons of stormwater running off of it.  That’s 600 gallons that are moving very quickly, picking up whatever is on the ground in your yard, carrying it into the storm drainage system, and emptying into the nearest waterway.  There are many ways to reduce the amount of stormwater that leaves your yard.  Collecting roof runoff in a rain barrel and using it later for yard irrigation, or diverting downspouts to a rain garden or natural area to allow water to soak into the ground are just a few.  How much stormwater runs off your roof? Just multiply the roof square footage X 0.6 (gallons per square foot per inch of rain).

The Middle

When it comes to stormwater pollution, the middle is where it all happens.   From your roof to the nearest waterway, anything on the ground or exposed to rain can become a pollutant!  And most of these sources of stormwater pollution come from our everyday practices:  fertilizers, pesticides and herbicides from yards and gardens, motor oil and grease from miles of roads and parking lots, heavy metals from roofs, eroded soil from construction sites and home landscaping projects, waste from pets, and litter and trash are carried by stormwater into the storm drainage system where it all flows untreated into waterways.

If you consider that 659,000 people live in Jefferson County, the amount of stormwater pollution that we generate each day is….. well, it’s a lot.  And since we get about 54 inches of rain each year, managing stormwater in your yard is a good place to start.  Anything that slows it down, spreads it out, and allows it to soak into the ground will make a positive difference in our water quality.

Creating natural areas and planting trees in your yard are excellent ways to prevent stormwater from leaving your property.  Depending upon their size, trees can absorb hundreds of gallons of stormwater every year.  In addition, the leaf canopy slows rain drops while the root system helps anchor the soil, reducing erosion.  When selecting and planting a tree, make sure that the site you choose will accommodate its full grown size as well as its water and sunlight requirements.

Reducing the need for irrigation and chemicals is another way to make your yard more stormwater friendly.  Consider using pavers to transform some existing high-maintenance turf areas into permeable patios or paths.  Pavers that are set into sand or gravel are a decorative and easy addition to your yard, and allow stormwater to soak into the ground.  Your new path or patio also will reduce yard maintenance since it won’t require mowing!

Mark Your Calendar!

March 27

Four Legged Gardening.  Grab a lunch and head to the Birmingham Botanical Gardens for a free Lunch & Learn Seminar from 11:30 – 12:30.  Discover how to create a safe environment for your pets by learning the difference between pet friendly and unfriendly plants.


Lyn DiClemente
Jefferson County Department of Storm Water Management
B-210 Jefferson County Courthouse Annex
716 Richard Arrington Jr. Blvd. North
Birmingham, AL  35203

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