provfsion, and then they convert the points into a net annual benefits score 

 using $70 as the base figure for a 100% score. 



They use a similar methodology for estimating visual amenity values 

 conferred by wetlands. They examined the prices paid by 29 municipalities for 

 various land parcels to establish the baseline price of a wetland scoring 100% 

 on a visual-cultural score point system. The water supply and flood , control 

 benefits were established in more conventional fashion. They used U.S. 

 Geological Survey data to estimate a cost differential between water produced 

 from yields produced by aquifers recharged by wetlands, and water produced from 

 well fields in the north Atlantic region. This cost differential wasjused to 

 estimate a capitalized and a net discounted annual benefits estimate. The water 

 supply point scoring system distinguishes a high ($2,800), medium' ($1,400) , and 

 low ($400) benefits level. 



A three-tier point scoring system was established for the flood prevention 

 function using U.S. Army Corp of Engineers data for the Charles River basin. 

 Gupta and Foster suggest that the total preservation benefits of any wetlands 

 can-be estimated by use of the point scoring systems. Whenever the preservation 

 benefits of some wetlands are higher than the benefits conferred by some project 

 involving drainage of the wetlands in question, the project should be abandoned. 



12. Larson, J.S. 1975. Evaluation models for public management of freshwater 

 wetlands. Pages 220-226 In K. Sobel , ed. Transactions: Fortieth North 

 American Wildlife and Natural Resources Conference. Washington, DC. 



» 



The author provides a framework for imputing various (levels of) 

 qualitative preservation benefits of the Nation's wetlands. This has meaningful 

 operational content from a management perspective because of the prohibitive 

 cost of a close examination of the preservation benefits of any particular 

 wetland. Larson offers a three-tier management-oriented wetland assessment 

 format. The first tier deals with distinguishing between "outstanding wetlands" 

 and those wetlands that do not fall into the exceptionally noteworthy category. 

 The defining characteristics of the exceptional wetlands are highly variegiated; 

 they include habitat provision for rare flora and fauna, habitat provision for 

 exceptionally beautiful flora, outstanding and unusual geomorphological features, 

 and the use of the wetlands as habitat by large numbers of water-, marsh-, or 

 shore-birds. 



The other two tiers provide an economic model for imputing wetlands 

 preservation benefits, and a qualitative framework for assessing the nonmarket 

 outputs of wetlands that do not belong in the exceptional category. The economic 

 model imputes benefits to groundwater recharge and reviews the acquisition costs 

 of various wetland types. The qualitative assessment model covers a variety of 

 outputs, including habitat provision for wildlife, potential for groundwater 

 recharge, and visual impact. The author restricts his discussion to the 

 glaciated inland freshwater wetlands of the northeastern U.S. 



13. Batie, S.S., and W.E. Cox. 1976. Economic implications of environmental 

 legislation for wetlands. Virginia Polytechnic Institute and State 

 University. Dept. of Agricultural Economics Research Report No. 29, 

 Blacksburg. 16 pp. 



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