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<br />. <br /> <br />. <br /> <br />. <br /> <br />Reservoir capacity is determined from USGS Quad map topography if <br />not available otherwise, e. g. Division Engineer' s office. The <br />reservoir volume is estimated assuming a straight line increase in <br />area between known areas at specified elevations. There is likely <br />to be a large error if Quad map topography is all that is <br />available. <br /> <br />The annual reservoir yield was generally assumed to be the <br />reservoir capacity. In most cases this is a very safe assumption, <br />but for some sites this would not be true; these cases are noted. <br />Also, an evaluation of the annual yield is recommended for further <br />study for some dam sites. <br /> <br />Cost Information <br />A reconnaissance level cost estimate is prepared for each dam site. <br />The cost estimate is plus or minus 25% and is included to generally <br />determine which sites may be feasible and which sites are clearly <br />not feasible. For purposes of this Study, "feasible" means the <br />sponsoring entity can repay the amortized construction cost. <br /> <br />The construction cost is the total of the embankment, outlet pipe, <br />and spillway costs. An amount of 30% is added for contingencies, <br />which is greater than the normal 20% because of the low level of <br />detail. The engineering and administration cost varies from 5% to <br />15% depending upon the difficultly of the design and the amount of <br />detailed data that is needed. For instance, if materials testing <br />has been performed in the past, the percentage can be decreased. <br /> <br />A mobilization cost is included for each darn site. The cost varies <br />considerably from nearly nothing to significant. The higher <br />mobilizations costs indicate access problems, particularly where an <br />access road must be reconstructed. <br /> <br />The embankment quantity is the largest factor in the cost estimate <br />and the cost per cubic yard to place material is the most difficult <br />to determine. Three costs per cubic yard were assumed depending-- <br />upon: (1) the difficulty of construction, (2) from previous studies <br />and (3) contractor estimates. Also, two of the entities have <br />contacted contractors in their local area, as noted for those <br />sites. The assumed cost per cubic yard are explained: <br /> <br />$2 per cubic yard - Used at sites with minimal difficulty <br />and the borrow area nearby or where the sponsoring entity <br />has data to support the cost. <br /> <br />$4 per cubic yard - Used at sites with average difficulty <br />where the borrow area is within a half mile and there are <br />no major problems with placement. <br /> <br />Small Dam Site Recon. Study <br /> <br />11 <br />