Tame runoff, say watershed experts
Saturday, September 28, 2013
HUNTSVILLE - As the population within the Beaver Lake Watershed continues to grow, residents will need to take increasing measures to mitigate the side effects of paving and construction, experts said Friday.
The importance of controlling storm-water runoff - a term for rainwater that can’t be absorbed into the soil because the land is covered with impermeable surfaces such as asphalt - was emphasized throughout several presentations during the Beaver Lake Watershed Symposium Friday at theCarroll Electric Building in Huntsville.
More than a dozen experts in hydrology, aquaculture and other biological sciences spoke before a crowd of about 60. While the topics of individual presentations ranged from the development and implementation of the Beaver Lake Watershed protection strategy to methods of stream restoration and water-quality testing, many of the speakers reiterated that one of the best ways to protect the region’s drinking water is to find ways of redirecting storm water into absorbent soils, rather thanlet it flow freely into open surface waters.
Katie Teague, an agent with the Benton County Extension Office, touched on several factors addressing water-quality protection while asking the audience to participate in a trivia game focused on water-pollution issues.
According to data provided by Teague and others, about 20 percent of rainfall in rural areas remains on the surface of the land as runoff when construction has made at least10 percent of the area impermeable. Teague said that a 1,000-square-foot house will displace 623 gallons of water from 1 inch of rainfall.
“From the homeowner side, it’s just the sheer volume of storm water that’s generated ontheir property, and pollutants that they can introduce that can be carried off their site, into a storm drain, untreated, into the nearest creek or stream,” Teague said. “We encourage ways to break up that path and slow down that water so it cansoak in.”
When water is allowed to permeate vegetation and existing soil, a natural filtration process can remove or reduce excess nutrients and other pollutants from the water as it makes its way into aquifers, and eventually into an area’s drinking water.
John Pennington, executive director of the Beaver Lake Watershed Alliance, has said he hopes the symposium will become an annual event. The alliance, a nonprofit organization founded in 2010, aims to promote awareness of factors that affect the quality of the drinking water in Beaver Lake,which is provided approximately to 420,000 people and sources its water from a watershed covering more than 1,200 square miles.
Brad Hufhines, an environmental technician with the Beaver Water District Treatment Plant, discussed how the use of “rain gardens” can help homes and businesses offset their impermeable footprint by creating areas of vegetation where storm-water runoff will pool and percolate into soil.
“We’re gaining 30 residents every day in Northwest Arkansas, so we’re becoming much more populated, much more built-out,” Hufhines said.“We’re covering up the natural land with impervious surfaces, and that’s causing a lot more water to flow into our streams rapidly. We’re getting more intense flooding and sediment from erosion that’s occurring at an increased level.”
Hufhines said the gardens, which are constructed in depressions to allow runoff to flow toward them, are effective and low-cost ways of trapping and filtering sediment and pollutants.
“I think that’s not the answer for everybody, but it’s one of several best management practices that can be used throughout the watershed.”
Northwest Arkansas, Pages 9 on 09/28/2013