Over the past three years, the University of California (UC) Santa Cruz installed five Truegrid permeable paver parking lots with a sixth on the way, totaling more than 150,000 sq ft. UC Santa Cruz chose the pavers after vetting several permeable paving options for their new Marine Biology Campus on the Santa Cruz, Calif., coastline.
Truegrid was selected due to its ability to handle the heavy traffic and loading required for a primary parking lot on a college campus. The patented design is a combination of vertical load strength and built-in S-Flex joints engineered to handle any subgrade movement from below and extreme surface loading from above.
The parking lots at UC Santa Cruz were permitted as 100% pervious cover and eliminated the need for detention that would have been required for these areas had the parking lots been concrete or asphalt. Each parking lot has a cross section that totals 10 in. deep. The base depth is 8 in. of clean, angular limestone and the permeable paver is infilled with a 3/8-in. crushed granite to complement the aesthetic of the coastline and architecture of the new UC Santa Cruz Marine Biology Campus.
Within the permeable parking lot’s cross section of 10-in. clean, washed, angular stone there is an additional 50,000 cu ft of storm water detention space that can be used to capture runoff from other hardscapes constructed during the project. The material was chosen for its surface performance ability and the campus’ need to reduce impervious cover, as well as its ability to assist in removing pollutants from vehicles and surrounding runoff.
The high flow-through rate of a Truegrid permeable parking lot, along with the bioremediation process of storm water filtering through the infill and base aggregate, is a best management practice for storm water quality. The storm water filters through the system into vegetated swales and then into the ocean several yards away. The system’s U.S. manufacturing and 100% post-consumer recycled material also were factors in UC Santa Cruz’s decision.