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Liquid waste disposal as a restriethe impact 



Although not generally regarded as a beneficial use, the discharge 

 of liquid Avastes to estuarine waters is and is likely to continue to be 

 one of the major universal uses of the estuarine zone. The present dis- 

 cussion considers liquid waste disposal as one of many uses of the 

 estuarine environment which has the potential of conflicting with 

 other uses but which will probably have to be accommodated within 

 the overall use patterns of nearly all estuarine environments. 



The major restrictive impacts of liquid wastes arise from the dis- 

 posal of untreated or inadequately treated wastes in massive quantity 

 to estuarine waters. The discussion in part IV, chapter 5, pointed out 

 the various pollutional effects different types of municipal and indus- 

 trial wastes can have, and presented some typical examples of pollu- 

 tional effects. Six types of impacts tend to restrict other uses: 



1. Floating or settleable materials make the system unpleasant or 

 destroy bottom-living organisms. 



2. Decomposable organic materials deplete oxygen necessary for 

 aquatic life and may cause nuisance conditions. 



3. Toxic materials destroy living organisms by killing them di- 

 rectly, damaging their reproductive ability, or poisoning their food 

 supply. 



4. Nutrient materials cause over-production of some ecosystem com- 

 ponents causing adverse effects on others. 



5. Pathogens create public health hazards. 



6. Heated waste discharges reduce available oxygen and cause other 

 adverse effects on the ecosystem. 



These kinds of impacts adversely affect the living resources or aes- 

 thetic quality or create a public health hazard. The damage to living 

 resources can be catastrophic when waste discharges are large in vol- 

 ume, strong in concentration, or prolonged in time. Such discharges 

 are restrictive rather than prohibitive, however, in that removal or 

 significant reduction of the waste discharge will permit a healthful 

 ecosystem to slowly reestablish itself with consequent full reestablish- 

 ment of the formerly restricted uses. San Diego Bay, discussed earlier, 

 is an excellent example of this. Commercial fishing, recreation, and 

 water supply are the major uses restricted by pollution ffom liquid 

 waste discharges. 



GoTmnercial fisMng as a restrictive impact 



Fisheries may be affected adversely either by damage to fishery re- 

 sources or by imposing a public health hazard which makes the harvest- 

 able product unsafe. The fishery resource, whether finfish or shellfish, 

 may be damaged by the direct killing of marketable species, by the 

 killing or poisoning of a necessary food supply, or by damage to the 

 reproductive capability of any part of the food chain. Any or all of 

 these may occur, depending on the waste discharge characteristics. 



Oysters, mussels, and clams are susceptible to these damages: in 

 addition, their meats may be made unsafe for human consumption by 

 the suspected present of wastes containing pathogenic organics or 

 toxic materials which such animals tend to concentrate in their tissues. 

 It is important to recognize that the conflict in use arises from the 

 inability to market the shellfish product because of necessary public 



