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P3 Research Project Search
EPA Grant Number: SU831880
Title: Using An "Impervious Permit" Allowance System To Reduce Impervious Surface Coverage for Environmental Sustainability
Current development dynamics and population projections suggest that further decentralized urbanization is likely to proceed into the near future, resulting in the continuing degradation of the physical environment. To begin to address this issue, P3 researchers designed a permit allowance system to reduce impervious surface coverage. The design establishes a "cap" on impervious surfaces on a per lot basis in watersheds of specific sizes. Similar to the Acid Rain "cap and trade" program, this policy design allows developers to trade "impervious surface credits" and offers flexibility in how developers choose to reduce impervious surface coverage. This innovative design applies market-based approaches to reduce pollution, making pervious or permeable surfaces a valued commodity.