other plants. Other predicted effects of 

 the discharge on the kelp forest include a 

 reduction in nearshore fish stocks due to 

 mortality of various life stages during 

 intake and/or passage through SONGS, a 

 reduction of mysid shrimp in and around 

 the kelp forest (Murdoch et al. 1980), and 

 an increase in fouling organisms on kelp 

 blades (Murdoch et al. 1980, Dixon et al. 

 1981). The kelp forest has been exten- 

 sively studied by the Marine Review 

 Committee (Murdoch et al. 1980), and 

 Southern California Edison Co. (reviewed 

 in McGrath et al. 1980), and before-after 

 discharge comparisons for the new units 

 should provide comprehensive information 

 on the effects of the power plant on the 

 kelp forest community. 



Another large nuclear power plant at 

 Diablo Canyon near San Luis Obispo has not 

 yet gone into full operation. This plant 

 has an intertidal discharge that will 

 release large volumes of heated water 

 directly into a small cove with a stand of 

 bull kelp ( Nereocystis luetkeana ) . Ele- 

 vated temperatures may eliminate bull kelp 

 and other cold water species in the cove, 

 and may affect populations in the vicinity 

 of the cove. Comprehensive baseline 

 studies have been done in the area by 

 Pacific Gas and Electric Company and the 

 California Department of Fish and Game, so 

 changes after discharge begins (assuming 

 the power plant starts operation) should 

 be well documented. It remains to be 

 determined how (or if) biological changes 

 observed at these sites will affect the 

 operation of the plants or the siting and 

 operation of future plants. 



Neither power plant is predicted to 

 cause significant changes in kelp forest 

 communities due to discharge of toxic 

 compounds. Over 1,000 dead abalone were 

 observed, however, in Diablo Cove after an 

 early cold-water test of the Diablo Canyon 

 Power Plant discharge system. Apparently, 

 sea water was held in the cooling system 

 for some time, and then released. The sea 

 water contained high levels of copper from 

 the condenser tubing, and when discharged, 

 caused the abalone deaths (Martin et al. 

 1977). Damage to other organisms was not 

 reported. The copper-nickel tubing has 

 since been replaced by titanium (Martin et 

 al. 1977). 



6.5.5 Sewage Discharge 



Domestic wastes contain nutrients 

 that may increase plankton productivity, 

 and thus turbidity, and may also contain 

 sludge particles that increase turbidity 

 as well as sedimentation rates and sedi- 

 ment thickness on the bottom. Industrial 

 wastes may cause similar effects, and also 

 may contain toxic metals and organic 

 compounds that can directly affect organ- 

 isms. Discharged pathogens may harm man 

 and other organisms. Thus, sewage 

 discharge has the potential of signifi- 

 cantly altering kelp communities and man's 

 use of them (Table 1). 



As discussed in Chapters 2 and 3, 

 there is good indirect evidence that 

 sewage from the Los Angeles area, dis- 

 charged in the vicinity of Palos Verdes, 

 contributed to the decline and eventual 

 complete loss of one of the largest giant 

 kelp forests in California. The decline 

 of the Palos Verdes kelp forest began in 

 the 1940's and 1950 ' s as discharge rates 

 increased. The community did not recover 

 after the warm oceanographic period of the 

 late 1950's (Grigg and Kiwala 1970, Wilson 

 1982). Increased turbidity (Eppley et al. 

 1972), sludge on the bottom (Grigg and 

 Kiwala 1970), toxic substances in the 

 discharge such as DDT (Burnett 1971), and 

 possibly copper (that can inhibit giant 

 kelp gametophyte growth and fertilization 

 at low levels; Smith 1979), and other 

 metals may have all contributed to the 

 decline and lack of recovery. With recent 

 improvements in discharge quality, giant 

 kelp has begun to return to the area 

 (Wilson 1982). 



A similar but less drastic decline 

 occurred in the Point Loma kelp forest, 

 one end of which is near discharges from 

 San Diego, and the other near the entrance 

 to heavily developed Mission Bay. As for 

 Palos Verdes, the decline at Point Loma 

 began near the sewer discharge area (see 

 figures in North 1976). Smaller, primari- 

 ly domestic waste outfalls appear to have 

 quite localized effects, and no general 

 adverse impacts have been reported. 



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