126 • Wetlands: Their Use and Regulation 



throughout the marsh. Draining and clearing of a 

 significant number of small, isolated wetlands for 



cropland have contributed to the decline of water- 

 fowl in the Central and Mississippi flyways (35). 



PREDICTING IMPACTS OF DEVELOPMENT 



ACTIVITIES 



Limitations 



According to U.S. Army Corps of Engineer reg- 

 ulations, "the decision whether to issue a permit 

 wlU be based on evaluation of the pro6afa7e impact, 

 including cumulative impacts of the proposed ac- 

 tivity . . . ." Under the Corps' public interest 

 review, the impacts of a proposed project must be 

 weighed against its other costs and benefits to deter- 

 mine if the project will be allowed. While there are 

 certain characteristic impacts associated with par- 

 ticular activities, it is clear that the actual impacts 

 of any project will vary with each site and project 

 and will depend on the time at which they are con- 

 ducted. This suggests that in most cases similar ac- 

 tivities or projects cannot necessarily be regulated 

 in a uniform way; the potential impacts of major 

 projects that might generate significant impacts 

 must be evaluated on an individual basis. 



Guidelines established for the 404 program rec- 

 ognize the variability that exists from site to site 

 and project to project. The 404(b)(1) guidelines, 

 for instance, require that the "permitting author- 

 ity .. . shall determine in writing the potential 

 short-term or long-term effects of a proposed dis- 

 charge of dredged or fill material on the physical, 

 chemical, or biological components of the aquatic 

 environment." This includes determinations of the 

 nature and degree of effect that a proposed dis- 

 charge will have on the following: physical sub- 

 strate, water circulation, fluctuation and sadinity; 

 suspended particulates/turbidity; contaminants; the 

 aquatic ecosystem and organisms; and cumulative 

 and secondary effects. 



Even under conditions of very careful site-specific 

 and project-specific examination, however, the abil- 

 ity to assess potential impacts accurately often is 

 limited. In general, the immediate effects of an ac- 

 tivity are easier to predict than long-term impacts; 

 physical-chemical impacts are more predictable 



than biological impacts; direct effects are more ap- 

 parent than secondary effects; and the impacts of 

 each project individually are much easier to predict 

 than the cumulative impact of many individual 

 projects. The short-term turbidity caused by dredg- 

 ing, for instance, is predicted relatively easily and 

 precisely; predictions of most cumulative impacts 

 are merely speculative. A study of the impacts of 

 deepening navigational channels on fish and wild- 

 life concluded that: 



Assessing the impacts of navigational dredging 

 and the disposal of dredged material is a controver- 

 sial exercise; the viewpoints and approaches are 

 endless. Without question, dredging can devastate 

 fish and wildlife resources; however, in the absence 

 of definitive information, impacts are sometimes 

 more imagined than real (1). 



It is well recognized that the routine application 

 of section 404(a) authority to issue individual per- 

 mits for the discharge of dredged or fill material 

 cannot provide for the assessment of cumidative im- 

 pacts on wetlands or other aquatic resources from 

 many individual projects that are evaluated sepa- 

 rately. The Corps' proposed general policies for 

 evaluating permit applications makes a clear dec- 

 laration: 



Although a particular alteration of wetlands may 

 constitute a minor change, the cumulative effect 

 of numerous such piecemeal changes often results 

 in a major impairment of the wetland resources.'' 



The separate examination of potential effects at 

 different but interrelated wetland sites cannot, by 

 itself, account for the cumulative effects. The 

 Corps' Environmental Advisory Board concluded 

 that: 



Individual permit processing in specific regions 

 is costly and ineffective in addressing the cumula- 

 tive impacts of existing and future similar permit 



^Federal Register, vol. 45, No. 184, pp. 62, 740. 



