Date: July 25, 2017
Maryland’s premier science education venue in the heart of Baltimore’s Inner Harbor showcases this reliable, green infrastructure technology: Pervious Concrete.
Pervious concrete is a unique blend of concrete that has interconnected holes allowing water to pass through but separates impurities and debris from getting into our waterways.
The Maryland Science Center (MSC) decided to retrofit one of their employee parking lots into a 3,700-square foot Pervious Concrete stormwater system. This plan was in partnership with the National Fish and Wildlife Foundation, Maryland Department of Natural Resources, the Maryland Ready Mix Concrete Association, and the Center for Urban Environmental Research and Education at the University of Maryland Baltimore County. This was the perfect project to use Pervious Concrete and help add to a swimmable Inner Harbor and Chesapeake Bay.
Urban construction can be challenging because it means uncovering centuries of past construction and buried infrastructure. Once unearthing began several unidentified obstacles arose:
- Buried 12-inch thick concrete foundation pads from industrial buildings that formerly covered the site.
- Underground electrical utility lines.
- Cobble stone pavement beneath the existing 8-inch thick concrete pavement.
- Hand laid brick drop inlet structure.
- Vertical 14-inch diameter stainless steel pipe of unknown usage and ownership.
Once the above obstacles were either removed or secured, a 12-inch stone subbase and storage layer was created to give structural support and ample stormwater storage for the Pervious Concrete.
For this existing parking lot, there was an expectation of very low infiltration rates in the compacted fill. Since this was an unusual site, a special solution needed to be established. To assist with the infiltration rates, a custom-fit membrane and a 12-inch diameter under-drain system was devised to transport infiltrated rainfall and runoff into sand filter galleries. The sand filter galleries will treat stormwater from the pavement's pervious reservoir before it’s discharged to the storm sewer system.
With this added resilience engineered in the Pervious Concrete, this became an educational showcase project for visitors to the Maryland Science Center. The pervious parking lot was finished in November 2016 and available for employee use.
When it comes to challenging projects, it is key to partner with excellent general site contractors, the best Pervious Concrete suppliers, and installers for a successful Pervious Concrete infrastructure project.
- UMBC Center for Urban Environmental Research and Education (CUERE)
- Maryland Science Center (MSC)
- National Fish and Wildlife Foundation
- Maryland Department of Natural Resources (DNR)
- Maryland Ready-Mix Concrete Association (MRMCA)
- Whitman Requardt and Assoc. LLP
- Environmental Quality Resources (EQR)
- Chaney Enterprises
- Z-Con Inc.