Towns in the Triangle region are growing fast. While growth brings jobs, it also puts pressure on our region’s ability to sustain us. The need for clean drinking water drives Triangle towns to pursue expanded access to water from Falls and Jordan lakes, and sometimes these competing needs flare up into heated debates.
But recently we’ve had nothing but rain, so why worry?
Data collected at the Raleigh-Durham airport shows that since the later part of 2013, our rainfall levels have trended above historical averages. But much of that rain has come in big storms and that causes a different problem for our water supply.
Mitch Woodward, a water quality specialist for the North Carolina Cooperative Extension Service, explains that yards unable to absorb the rain from a big storm produce a lot of water running off into the stormwater system. That water courses through the system and drains into streams that lead to rivers and lakes.
According to Woodward, “We’re going to get more and more run off from storms and that increases the velocity of the water in the stream and that causes erosion. Most of that is sediment, which is North Carolina’s number one pollutant. Sediment, dirt and water, is our number one pollutant and is caused by localized stream bank erosion.”
It surprises me that sediment is our biggest pollutant. But as that organic muck gets into our streams, rivers, and lakes it decays and reduces the water’s oxygen levels which can lead to fish kills and algae blooms, and that requires more chemical treatment to make the water drinkable. A complex issue of towns fighting for greater access to clean drinking water begins as something as simple as the rain falling on the roof of my house.
If I add together my roof, driveway, sidewalk, and patio, my little patch of suburban heaven is pumping out nearly 3000 gallons of water run off every time it rains one inch. A simple calculation is that for every 1000 square feet of impervious surface, each inch of rain produces about 600 gallons of water.
Local municipalities are working to restore stream banks to slow down the problems caused by erosion. It’s expensive and can be a slow process. But business and homeowners can help by reducing the water running off from their property.
Steps you can take can include disconnecting your downspouts that discharge directly into the stormwater system and redirecting that water to infiltrate an area on your property.
Or collecting that rainwater in a rain barrel or cistern so you can use it later during a dry period. Installing a rain garden in a wet area on your property will help absorb the water rather than letting it flow away.
We can help educate our friends and neighbors about the connection between rainwater, how we manage our yards, and drinking water quality. Our drinking water supply is a resource we all share and can all help protect.
The following resources have ideas on how you can reduce the amount of stormwater flowing off your property.
Alamance County – www.alamance-nc.com/planning/programs/stormwater-information.
Chatham County – www.chathamnc.org/index.aspx?page=882.
Durham County – durhamnc.gov/ich/op/pwd/storm/Pages/RainCatchers.aspx.
Franklin County – www.franklincountync.us/services/soil-and-water-conservation.
Granville County – www.granvillenc.govoffice2.com.
Johnston County – www.johnstonnc.com/mainpage.cfm?category_level_id=546.
Lee County – www.leecountync.gov.
Orange County – www.orangecountync.gov/DocumentCenter/View/3918/Rain-Gardens-for-Orange-County-PDF
Wake County – https://raleighnc.gov/news/2018-04-05-raleigh-rainwater-rewards-stormwater-program-helps-citizens-recycle-rainwater
Dr. Lise Jenkins is a Durham County Extension Master Gardener Volunteer.