The Service has determined that the new water quality measures which are an optional addition to the Texas Commission on Enviromental Quality's (TCEQ) Edwards Aquifer rules will also serve to protect four Federally-listed endangered and threatened species and one candidate for listing.

These water quality measures are now an option for developers going through the TCEQ authorization process. The optional measures include a variation of current "best management practices" (BMP) performance requirements, which are practices implemented to reduce the impact of developer activities on water quality in and upstream of the aquifer. They also include measures to address stream channel erosion resulting from increased impervious cover, sensitive feature protection practices, guidelines for sealing sensitive features, and methods to improve BMP maintenance documentation. These new measures will be an appendix to the technical guidance document for Edward Aquifer rules issued by the TCEQ.

In addition to the optional water quality measures, the agencies will join forces with other agencies such as the U.S. Geological Survey to operate a more elaborate water quality monitoring network in order to continually evaluate both the short and long-term water quality in the Edwards Aquifer. If the monitoring data raises concerns regarding water quality, the agencies will analyze the data and review the water quality control measures.

The Service believes the optional TCEQ measures add a level of security that protects the Barton Springs salamander, San Marcos salamander, Georgetown salamander (a candidate for listing), San Marcos gambusia, and the fountain darter from adverse water quality impacts. Other species may be added later.

Currently, development projects must receive a water quality authorization from the TCEQ, and also demonstrate to the Service that there is no impact to an endangered species in the area of the proposed development. Under the new process, developers who opt to comply with the new TCEQ measures will receive a water quality authorization through the TCEQ deemed by the Service to comply with endangered species requirements in some cases. Some situations will still warrant direct consultation with the Service, including projects requiring a federal permit,impacting listed species which are not water quality related, and impacting other listed species not covered by the measures.