Both sites had heavy clay soils and are busily used public parking lots.
Tualatin Hills Parks & Recreation District (THPRD) Redevelopment
The THPRD site was a complete redevelopment. At the point that we presented our idea to incorporate trees into parking lots, a plan was already underway to remove all the existing asphalt in the parking lot and replace it with pervious concrete. We added our Parking Forest as an overlay onto the project, adding 15 trees to the new parking lot.
Portland Community College (PCC) Retrofit
The site at PCC was an existing conventional asphalt parking lot, but most of it was left in place. Only a small 12' wide by 34' long piece of pavement was disturbed and 8' of that width of pavement was replaced to ensure that the final parking stall would be adequate.