Download Full Text (900 KB)

Document Type

Book Chapter


Virginia Institute of Marine Science

Publication Date


Book Title

Chlorine - Bane or Benefit? Proceedings of a Conference on the Uses of Chlorine in Estuaries


Chesapeake Bay Foundation, Chesapeake Research Consortium and Citizens Program for Chesapeake Bay


CRC Publication No. 104


Two primary uses of chlorination in estuarine systems are disinfection of sewage effluent and fouling control in condensor tubes of electric power generating plants. The intent in both uses is to apply sufficient chlorine to kill certain target organisms. At the same time, however, efforts are made to control both the application rate and effluent release so that non-target species in the receiving waters are not affected. To accomplish such control, the effluent is usually retained, which permits the decay of the residual chlorine and rapid dilution with ambient water to reduce further the residual. The residual concentration continues to decay in the ambient water through a series of reactions outlined in Dr. Helz's paper. If all goes well, no adverse impacts can be expected in the receiving waters.

However, ·at least two disquieting instances of chlorination's possible impact in the Chesapeake Bay have been observed.

Acute Toxicity Potential of Chlorination in Estuarine Waters