July 17, 2013
By Don Rissmeyer, P.E. CFM
New and innovative stormwater management approaches are appearing every day through the creativity and experience of stormwater professionals. One of the technologies gaining traction with our clients is permeable pavement, especially in urban areas where land is unavailable and costs are at the highest. Permeable pavement eliminates the need for a stormwater management tract by placing the treatment system under roadways and parking lots. Runoff drains through the wearing surface into the reservoir stone underneath where it is stored and infiltrated in the soils below. Depending on the extent of the rainfall, the amount of storage volume, and the underlying soil conditions, the result can be significantly reduced amounts of runoff with greatly improved water quality. The biggest drawback to permeable pavement right now is the high cost of the paving system and the underlying reservoir stone which are consistently among the costliest of stormwater management solutions. This leaves us asking: What innovations are available to make a permeable pavement system both high performing and low cost, to encourage more widespread implementation?
Do you believe that if a high-performing permeable pavement system were to take over our public and private roadways, we could virtually eliminate the negative effects of urban runoff? And how do we reduce the cost? Do we choose permeable asphalt, concrete, interlocking blocks, or grid systems? Do we need underdrains in low infiltration soils, and how do we enhance infiltration on sites? Are there other innovations being made to lower costs without sacrificing performance? The gauntlet has been thrown to the most insightful and creative reading this blog… can permeable pavement be the path ahead at a lower cost?