Appendix I 



Techniques and Sources of Data for 

 Determining Pre- and Post-Construction 

 Agricultural Output from Reservoir Areas 



Soil Capabilitie:^ Classes 



The productivity of the land in the site can be rated according to its best 

 usage in terms of soil type, slope, and erosion. I See Appendix Table I.) 

 Output can then be derived under prevailing and optimum management 

 conditions. (See Appendix Tables IV and V.) 



Estimates of this type were derived for the present ( pre-construction) 

 ])eriod in an analysis of the effects of the proposed Hopkinton-Everett project 

 on agriculture. In this particular study, it was indicated that no attempt was 

 laade to estimate the value of production in the reservoir site during the 

 post-construction period under either prevailing or optimum management 

 conditions. The report indicated such a determination would require reli- 

 able predictions of the frequency, depth, and duration of inundation: the 

 character and size of farms immediately surrounding the site; and the re- 

 sponses of farm operators and management policies.^ 



The principal drawbacks to deriving estimates from soil capability classes 

 are as follows: 



(a) If the technique is applied in an aggregative sense to all the land, 

 ownership boundaries are ignored. 



(b) Use of average yields will not allow for management variations 

 from farm-to-farm. 



(c) Results for the individual units might be impractical if individual 

 fields were parcelized into a number of capability classes. 



(dl Soil capability data is not available for all the existing and potential 

 reservoir areas. Hence, until such information became available, the tech- 

 nique could not be used universally. 



( e ) Goals established strictly from the conservation approach are not 

 necessarily the same as would be derived from the totals of unit planning 

 wherein maximization of producer returns and/or reductions in food costs 

 to consumers are reflected. 



(f) Soil capability data are most useful in planning programs for existing 

 or potential reservoir areas. Together with photointerpretation data and 

 data on the expectations of flooding and a pattern of land use consistent 

 with the requirements of efficient farm enterprises in the area, such data 

 can become the basis of management policies. However, soil capability data 

 of itself does not directly involve specification of land use and/or type of 

 cover. 



^ "Social and Economic Impacts, Proposed Hopkinton-Everett Reservoir, Merrimack 

 River Basin. New Hampshire,"" edited and published by Planning Division, N. H. State 

 Planning and Development Commission, March, 1955, p. 17-18; Appendix II, table K. 



47 



