City of Surrey constructs parking lot with pervious concrete to infiltrate and capture rainwater
In summer 2008, City of Surrey – Parks, Recreation & Culture Department began construction of the Clayton Dog Off-Leash Park, located at the northwest corner of 188 Street and 70 Avenue in Surrey, BC.
The park design includes a separate small and large dog area, with separate entrances and green buffers and fencing dividing the two dog areas. The project also includes a parking lot of approximately 1570 m2 (16,880 ft2) in size.
“To provide first flush pollution control and rainwater management, the decision was made to utilize pervious concrete as the pavement surface for the construction of the parking lot,” reports David Hislop, City of Surrey Drainage Engineer.
“By incorporating a base course (open-graded crushed rock) layer of 250 mm beneath the pervious concrete, the total storage capacity provided by the pavement system is calculated to be 137 m3 of rainwater. This exceeds the required storage volume of 128 m3 based on the 5-year 24 hour rainfall event.”
“One of the most important lessons learned during the demonstration placements and the construction of the pervious concrete parking lot is that creating pervious pavements is not as simple as it looks.”
“The use of water reducing admixtures in combination with viscosity modifying admixtures significantly reduced or eliminated most of the previous difficulties experienced placing pervious concrete pavements. Much of the hard physical labour was eliminated and the quality of the finished product was improved. This is a major milestone in facilitating successful placement of quality pervious concrete pavements,” concludes David Hislop.
For complete details, click on City of Surrey Pervious Concrete Project Report – April 2009. The report provides technical information on design principals used, materials, properties, construction methods, testing and inspection. Also included is a discussion regarding material and installation costs, as well as, maintenance requirements when using this material.
Posted June 2009