Dripping through the Cracks

Drive around Houston, and it can be hard to find any green ground around all that pavement. Blanketing the earth with concrete can cause problems, from storm-water runoff to heat capture. But the Houston Parks Board is finding one small way to break through the concrete-and reach the earth below. From the KUHF NewsLab, Melissa Galvez reports.

In the middle of a rainstorm, the parking lot at the offices of the Houston Parks Board looks like many others.  But when the downpour stops, it’s easy to see the difference.

“The water would puddle in the grass areas all around, and so those would turn to mud, and then on the concrete drive that feeds in, water ponds on the concrete, but here where the pavers are, the water drains straight through, so this area is dry, but you’ll have water standing on both sides of it.”

That’s Trent Rondot, Projects Manager at the Houston Parks Board.  The HPB is a non profit that raises money to buy parkland, and advocate for parks.  Recently, they redid the parking lot with “permeable pavers”: in this case, pink, red, and gray bricks that let water sink through the cracks to a layer of sand below. 

Permeable pavers are more eco-friendly than your typical black cement for two reasons: Number 1, they cut down the amount of water rushing through the streets, by returning it directly to the ground.  Number 2, they help clean the water.  Here’s Chairman of the Board of the Bayou Preservation Association, Kevin Shanley:

“When you park your car, it will probably drip a little oil, or you put your brakes on, and every so often you have to replace your brakes.  Well guess where all that brake stuff goes? It goes onto the road. And so when it rains, if it’s just on an ordinary solid concrete driveway, the rain will wash all that stuff off your driveway, which is nice, but guess where it goes? It goes into the bayou where the fish are, and it goes into Galveston bay, where we got the shrimp, and oyster, and other things that are drinking that water.”

With permeable pavers, water gets filtered by the sand on its way to the dirt; and it doesn’t collect as much junk running through the streets.

But these pavers are not ordinary bricks.  Green construction company VAST Pavers makes them out of 95% recycled tires and plastic.  Here’s Director of Sales Scott Sester:

“We chose those materials because rubber and plastic are two of the materials that sit in our landfills the longest.  And we wanted to have a product that we thought was also going to last a very long time.  So by taking these out of the landfill and putting them into a product that is aesthetically pleasing and incredibly durable, that’s how we feel green construction should be handled.”

Some might worry that the pavers won’t hold up to traffic.  But Sester says the bricks are engineered to withstand a fully loaded semi, or even a snow plow.  They’re not ready for roadways, but work on sidewalks and driveways.  Though they cost a little more than regular pavers, Rondot hopes others will use this new way to go green.

From the KUHF NewsLab, I’m Melissa Galvez.