By Renee Frith
Bernheim Arboretum and Research Forest is thrilled to announce the opening of our newest environmentally sustainable addition, our permeable paver parking lot, located across from the Visitor Center, adjacent to Playcosystem. A portion of this lot will be open starting Saturday, July 17.
Bernheim hosted approximately 200,000 visitors, members, school groups, campers, and nature enthusiasts in 2020. On a good day, parking can be hard to come by, and we knew we needed to increase parking capacity to support our new play space, Playcosystem. Playcosystem is designed in harmony with nature, so why should our parking lot be any different? There are 144 parking spaces, of which 15 are permeable concrete, 51 are recycled asphalt, and 78 are grass pavers from Invisible Pavers – Grass Pave 2. The grass paver area will be used for overflow parking. The seed used in the grass pavers is a mix of Kentucky bluegrass, rye, and fescue.
Permeability is all about porosity. The grass seed was sewn into an engineered sand mix that will allow for peak water filtration. The permeable concrete section contains a specialized concrete mixture, which allows water to move through the concrete instead of running off into surrounding areas. The benefit of permeable pavers is that any pollutants such as oil, gas, brake dust, etc. that is left in the parking lot after cars leave will remain until a rain comes. The water from the rain will collect these pollutants, which will then be leached (filtered) down through the permeable pavers and into the soil layers below resulting in cleaner ground water.
While the asphalt section may not be permeable, it was made by milling off only a small percentage of the existing asphalt and then replaced a top coat made with 20% recycled asphalt. By removing and replacing only necessary asphalt, we were able to spare quite a bit of new materials. It is graded in a way that will slope into our new rain garden. Currently, both the rain garden and parking garden are planted with trees, shrubs, and pollinator friendly perennials. This fall, we will install more perennials and overseed with a perennial mix. Plants, in conjunction with permeable pavers, make for an efficient use of water while providing carbon sequestration value. We hope you enjoy our newest contribution to environmental sustainability and are inspired to use similar materials in your future home improvement projects.