Sometimes, being popular has disadvantages. In Montgomery County, MD, the area’s good schools, low unemployment rate and proximity to Washington, D.C. and Baltimore have led to an increased population density. To construct enough housing and commercial properties to support those residents, numerous neighborhoods have been built over existing streams, leading to erosion, minor flooding and property damage.
Fortunately, new solutions are being employed, and permeable interlocking concrete pavement (PICP) is one of them. PICP emerged as a solution after a pilot project identified tactics for creating healthier local landscapes conducted about 10 years ago. In response, the County’s Department of Environmental Protection created RainScapes, a pioneering program focused exclusively on reducing stormwater runoff and improving water quality in affected neighborhoods.
Designed to incentivize and implement projects that reduce stormwater runoff, RainScapes offers technical assistance and advice with a rebate program that pays homeowners and commercial building owners to use PICP among other tools. Other RainScapes techniques include tree planting, conservation landscaping, dry well installation, green roof implementation, rain garden design and cistern installation.
One of the most popular aspects of the program has been permeable pavement because the rebate helps offset the high installation costs. For residential projects, the rebate maximum is $2,500 and commercial or multi-family projects can be eligible for a rebate of up to $10,000. To receive a rebate for permeable pavement for residential properties, a homeowner must hire a Montgomery County certified contractor and convert a minimum of 100 sf (9 m2) of hard surface to PICP.
For commercial, multi-family and institutional properties, a minimum of 300 sf (28 m2) must be converted.
The amount of the rebate is meant to cover the cost difference between traditional pavers and permeable pavers, says Dan Somers, who oversees the RainScapes Rewards Rebates. “This is a way to get homeowners to feel more comfortable with permeable pavers,” he says. “When you remove that cost difference, they’re able to compare the options based on factors other than budget.”
In addition to providing the rebate incentive, Mr. Somers visits the project site, talks with homeowners and explains the programs in detail. Sometimes, a homeowner might take on several projects, like installing a rain garden and planting canopy trees, as well as considering permeable pavers.
Although PICP doesn’t make sense for every property, they’re often chosen for residential projects, Mr. Somers says. “Permeable pavers are modular, with a predictable quality, and we have good data on them for the scale of projects that we’re doing, so they come with many advantages.”
Homeowners in the county consider PICP for a number of reasons, says Ann English, RainScapes Program Manager for Montgomery County. Some want to make the property look nicer, while others might want to reduce runoff because they’ve had runoff problems in the past. Some just want to do something for the environment, she adds.
When the RainScapes program started, Montgomery County contacted the Interlocking Concrete Pavement Institute (ICPI) for assistance in creating a successful program that would draw interest from homeowners and contractors. The county’s design manual for the RainScapes program was developed with input from ICPI staff who provided technical review of the material.
In addition to the manual, the County developed a professional training course geared toward contractors who want to learn the nuances of a permeable paving system. The daylong class covers stormwater basics, installation processes, troubleshooting and rebate specifics, so they can be more familiar with the program.
Once they complete the course, contractors are included on the County’s “professionals list,” which can be accessed by homeowners and commercial building owners. The list also includes information on how many rebates contractors have garnered, so those perusing the options can determine level of experience with permeable paver projects and RainScapes rebates.
For homeowners and other building owners, the County offers a series of consumer-friendly manuals on the RainScapes website that give more detail about potential projects and show photos of successful installations. For example, on the permeable pavement page, the Department of Environmental Protection includes a slideshow of permeable paver projects, including “before and after” photos that give a homeowner a sense of what installation might include. The website also contains information on how a homeowner can assess a property to determine the best location for a permeable paver project, and actions that can be taken to maintain it after installation.
With over 40 residential projects completed, Ms. English and Mr. Somers have a sense of the program’s effectiveness, finding that the RainScapes projects show significant success in handling stormwater. Although there’s some pressure from outside sources to include porous concrete or other alternatives in the program, RainScapes remains focused on PICP because of its numerous advantages, says Ms. English.
“They’re easier to clean for homeowners, and we feel very comfortable with a system that includes pavers that must be recognized by the ICPI,” she notes. “There’s an extra level of credibility and support there.”
Local contractor Mike Walters, owner of First Impressions Hardscapes in Sandy Spring, MD, installed permeable pavers on about 30 residential properties as part of the RainScapes program. In total, he’s done close to 300 projects with permeable pavers in the county. He shares Ms. English’s opinion that permeable pavers provide several benefits that would be challenging to replicate with other pervious or porous paving materials.
“The pavers are aesthetically pleasing, but what’s genius is the system below them,” he says. “That’s driving demand, because people are looking for new ways to handle water problems on their property, and using a permeable paver system dramatically cuts down on water runoff.” Mr. Walters installed a permeable paver system on his own driveway and uses the captured rainwater to water his lawn.
As an advocate of better stormwater management, Walters believes the RainScapes program could be a boon for any community, city or county as most have too much stormwater runoff. “The program is awesome, there’s great incentive for people to invest in a greener alternative here, and you’re getting an attractive product at a better cost,” he says. “In this situation, everybody wins.”
To learn more about the Montgomery County RainScapes program, visit www.montgomerycountymd.gov/DEP/water/rainscapes.html