Grass growing green in library parking lot
June 9, 2008 · Updated 5:26 PM
The project puts rainwater back into the ground instead of the storm system.
Grassy and parking lot dont often turn up in the same noun phrase.
But the Bainbridge librarys new south parking area demonstrates that the two concepts can coexist, as the distinct hue of green has supplanted the usual black of asphalt beneath patrons tires.
The idea: to save the expense of an extensive underground stormwater detention system, by making the parking lot itself such a system.
Plus it looks nicer, said Jim Laughlin, a member of the library board who coordinated the project. Itll look great. People will wonder if they can park their car here.
They can, and are, since the lot was completed and a new entrance way off Madison Avenue opened up last week. The new 7,500-square-foot surface, coupled with a planned restriping of the old parking area near the building, boosts the librarys capacity by about 20 spaces.
The south property was purchased by the library board several years ago with expansion in mind; development of the parking area got under way this past spring. But the unusual parking surface, a commercially available variety of paver called Turfstone perhaps more closely associated with patios and walkways, is just that: the surface.
Their diamond-shaped gaps already tufted with hydroseeded grass, the stones are the top layer of a sandwich of materials designed to keep rainwater from flowing offsite.
Below the pavers rests a layer of sand used to create a level surface for the stones. Next comes a woven fabric membrane to keep the sand from slipping down into the eight inches of rock that forms the foundation of the parking area, and into which rainwater collects.
Thats your detention, so to speak, Laughlin said. Its a place where the water can stand until it can perk down into the soil.
Finally comes another membrane to keep the rock itself in place.
The pavers are marketed by a Virginia-based outfit called Interlock Paving Systems, which bills its product as a way to cut down on stormwater runoff and maximize groundwater recharge in developed areas.
Ergo the interest of Laughlin, who has built various residential and commercial projects on Bainbridge Island and in North Kitsap. He took the idea to the library board, which signed off.
Im in the development business, and I study all this stuff, he said.
Project participants included Adam and Goldsworthy surveying, Fairbank Construction and Browne Engineering.
I just leaned on all the people I do business with, said Laughlin, who has developed various residential projects around the island.
He credited the city Department of Public Works with allowing the unconventional approach, believed to be the first or certainly the largest such lot for a commercial building in Winslow.
You can try to be the most forward-thinking person, Laughlin said, but if the regulations wont let you, you can have the best idea in the world but you cant do it.
Randy Witt, public works director, said the city will encourage such alternate methods of stormwater retention, as new standards by the state Department of Ecology are adopted.
The layers of materials are said to have a filtration effect on pollutants from vehicles, like oil leaks.
The lot does include an overflow system, so in times of particularly heavy rainfall, water that isnt absorbed will be carried off to the nearby storm drain conveyance.
On a recent afternoon, a passerby gave the project high marks.
I like it, he said. It doesnt cover the earth with concrete.
Said Laughlin, Everybody who sees it says its a pretty cool deal. Why not?
Whatever its merits, the turf-n-paver parking lot is not for everyone; women in stiletto heels are among several constituencies who might want to stick to the regular asphalt surface.
Skateboarders will have a little trouble, Laughlin said. Poor devils.