Permeable pastries: Jerry Ray, left, and Mike Regans on Mickey's Pastry Shop's permeable pavement. Art Latham photo
Sound research means establishing solid baseline data.
And the means of acquiring stormwater runoff baselines are in place and in use at several locations around the state, in the form of permeable pavement projects.
Permeable pastries: Jerry Ray, left, and Mike Regans on Mickey's Pastry Shop's permeable pavement. Art Latham photo
Jerry Ray, owner of Mickey's Pastry Shop, is well pleased with the look and performance of the permeable pavement and the rain gardens that accompany it at one of these sites, which encompass part of his store's parking lot.
Mickey's, in Goldsboro, is one of several sites around the state where Neuse Education Team (NET) members are running baseline projects to determine which permeable pavement type works best for which North Carolina soil conditions.
NET member Mike Regans, N.C. Cooperative Extension area specialized agent for environmental education in Greene, Lenoir, Pitt and Wayne counties, says Ray's parking lot's permeable pavement project came about due to good luck.
"Bill Hunt and I were in the courthouse downtown talking to the city engineer about where to go next to demonstrate BMPS for compliance with the 1998 stormwater regulations," says Regans. "He said, 'Y'all should go talk to Jerry Ray next door at Mickey's.' So we did, and he liked our ideas and has become a great cooperator. It's been excellent to work with Jerry."
That was about a year ago, before Ray moved the store to its present Graves Drive location from its site next to the County Courthouse, where it had become a Goldsboro icon in its more-than-70-year history.
Ray thought his new building called for a new approach to stormwater drainage. So to gain a research area, Regans and Hunt agreed to make up the difference in cost between a standard, all-asphalt parking lot and an environmentally friendly one bordered with permeable pavement. That turned about to be about $2 per square foot over a 32,000 square-foot lot, with the shop taking up much of the area.
The entire installation process took about three days, Ray says.
"We've had heavy rains recently and this whole pavement area has worked magnificently," Ray says.
"The raingarden held the runoff and the overflow area [ed.'s note: a bioretention area] held anything extra. It's done exactly what it's supposed to do: It keeps the stormwater from running into Stoney Creek; it just sits and percolates into the ground. By the time it gets to the Neuse River, it's got to be clean."
Other sites are in Kinston, the longest-running study, and in Swansboro, New Bern, Wilmington, Raleigh and Carteret County. All sites rest on a one-to-two inch bedding layer of sand or fine gravel. Workers add a base depth of 6-to-10 inches of washed 57 stone, fill with pea gravel or sand, then install the pavers. At Kinston, researchers installed Turfstone, a grid paver. The other sites use interlocking concrete pavers or a product known as porous concrete.
"Except for Raleigh, all sites were placed over loam or sandy loam soil," Hunt says. "The Raleigh site is to study the effects of clay soil on the pavement's performance. We're not necessarily endorsing permeable pavement's use in clay soil at this point, but this research will help us decide if we will."
NC State University graduate students in the Biological and Agricultural Engineering or Civil Engineering departments designed all sites. BAE graduate student Eban Bean is conducting research at all sites, under Hunt's supervision.
Getting a lock on water quality: NC State graduate student Eban Bean points out the interlocking pavement at a Wake County site. Art Latham photo
Bowling for drainage? Bill Hunt indicates drainage area for the porous concrete pavement on which he stands during a field trip to a research project at Ann McGrary Park in Wilmington. Art Latham photo
