Are We Still In "Hot Water" Over Thermal Discharges?

Thermal ecology research and analysis are far from passé. Despite use of closed-cycle cooling at new thermal power stations, thermal effects remain important for the electric power industry and others with thermal discharges. Once-through cooling at existing facilities must meet water temperature standards in the water body or obtain a Clean Water Act §316(a) alternative thermal limitation (variance). Thermal modeling and biological assessments are needed even though the discharges (e.g., from cooling-tower blowdown) are small and meet standards. Temperature standards in many states need better scientific basis in thermal-effects information for aquatic species. Demonstrations for §316(a) variances face increasing scrutiny for showing a Balanced Indigenous Community that would have been there in the absence of the thermal discharge and for “no prior harm” that includes long-term trends in aquatic populations. Repeated biological surveys for permit renewals need to improve understanding of the local thermal ecology as well as tally current populations. The science of community aquatic ecology has yet to mesh well with the regulatory criteria for “balanced.” Innovative approaches are needed for scientific research, impact analysis, and translation of scientific understanding into regulatory standards and procedures.  Enhanced understanding of thermal ecology in relation to thermal discharges needs to be more effectively communicated among relevant parties: regulators, educators, consulting firms, company personnel, and opposing groups.