In San Marcos, Texas Code of Ordinances, Chapter 94 Development Standards, Edwards Aquifer Protection Regulations. The purpose of this ordinance is to protect the Edwards Aquifer from pollution. The aquifer has significant environmental, economic, and recreational values. The ordinance regulates development over the aquifer in order to protect health and environmental features such as endangered species. It functions by limiting impervious coverage in the recharge and transition zones of the aquifer.