COMPILATION OF WATER POWER REPORTS 651 



When circumstances render it inadvisable to visit the upper 

 waters of the basin for the purpose of personal inspection, a review 

 of the storage situation, as far as it can be gathered from existing 

 maps and from local information, should be included. 



The surface area and capacity of all storage reservoirs consid- 

 ered, together with the area of the drainage basins adjacent to the 

 same and their sufficiency to fill the reservoirs, should be fully 

 covered; the beneficial effect of such storage on the flow of the 

 river should be discussed. 



(6) Prior Water Rights. Any existing or projected schemes of 

 municipal water supply, irrigation or water power, which have 

 diverted or may in the future permanently divert a portion of 

 that river flow, thus reducing the water available at the site, 

 should be investigated and reported on. 



(7) Ice Conditions. The general conditions in winter along the 

 river as a whole, covering time of freeze up, conditions in mid- 

 winter, and time and manner of break up in the spring, should be 

 secured from whatever local sources may be available, or, if pos- 

 sible, from personal observation. The question of anchor and 

 frazil ice under present conditions should be considered carefully, 

 also that of ice jams in the spring, both above and below the site. 

 The possible formation of ice jams below the site and the conse- 

 quent effect on the tail-water and floor elevation of the power- 

 house, should be particularly noted. 



The frazil and anchor-ice conditions, to be anticipated at the 

 site after the construction of the plant, should be discussed. In 

 this connection a careful study covering the winter conditions and 

 troubles experienced in the operation of any existing plants on the 

 river, together with methods of remedying the same, is advisable. 



The probable effects on ice conditions of the development of 

 storage for the purpose of increasing the winter flow, should also 

 be covered. 



V. Description of Existing Power Plants 



Existing power developments along the river should be dealt 

 with under the following general heads: Ownership of plant and 

 when constructed; description of layout and structures (dam, 

 intake, penstocks, tunnels, canal, forebay, power-house, founda- 

 tions, transmission, substations, etc.), and present conditions of 

 the same; head at different seasons; installation (electrical and 



