A new campus building created the need for additional parking. Based on a Zero Impact Feasibility Study (“Zero Impact” referring to a set of development standards with regard to environmental impact), the college decided to intensify its use of existing parking areas rather than clearing more forest, meaning that the required 350 new parking spaces needed to be added without increasing the existing footprint.
With every maintenance or redevelopment project on the campus, the goal is to reduce the environmental impact wherever practical. The objective with the chosen pavement solution was to handle a 100-year, 24-hour storm without surface runoff. A permeable paving approach was favored because it negated the need to clear and grade surrounding forest areas for detention ponds.
The College was presented with three alternate solutions to choose from: GrassPave2™ – an extrude plastic product, GravelPave2™ – a system of crushed rock with cellular confinement, and Uni Eco-Stone®. Uni-Ecoloc®, a fourth alternative, was approved just prior to bidding because of its mechanical installation efficiency. Uni-Ecoloc was chosen because it offered the College an environmentally responsible choice that was also durable and reasonably economical. The costs were determined to be the same as, or lower than, traditional alternatives using new treatment and detention systems. As the Ecoloc pavers were mechanically installed, additional time and labor savings would be realized.
The system is designed to control stormwater runoff, treat it, and reinfiltrate it into the water table. The innovative design added new parking by removing and reshaping planting islands and reorganizing lanes. The design included infiltration to the subgrade and storage in rock ballast under the pavement. Runoff from the parking lots currently discharges to the nearby East Fork of Houston Creek without treatment or detention; the college felt the ideal solution would reduce the amount of runoff to the Creek. The combination of adding new permeable paving and converting existing paving to permeable surfaces is expected to result in the desired net reduction in runoff.
Ecoloc Pavers provide monitoring and teaching opportunities for students in the college’s environmental studies program since students will be able to observe surface infiltration rates and easily remove a few pavers to examine the base materials and analyze pollutants being leached out of the water.