Record Details
page 99
Digital Collections at BYU
| Field | Value |
|---|---|
| Title | page 99 Central Utah Project, Bonneville Unit : Diamond Fork Power System : final Environmental Impact Statement, page 99 |
| Coverage | Electronic reproduction; |
| Format | 99 text/PDF |
| Rights | Brigham Young University; http://lib.byu.edu/about/copyright/generic.php Public Domain Public |
| Language | English; eng; en |
| Relation | Central Utah Project; Western Waters Digital Library; CHAPTER 111 III ili alternatives other alternatives in terms of dissolved oxygen all of the alternatives are basically equal in impact except the no power alternative which would have greater impacts at times As explained in footnotes 14 and 15 of table 20 surging f flows lows in diamond fork under the 1964 DPR alternative would cause a slight increase in relative background turbidity and the other power alternatives would significantly decrease existing turbidity because reservoirs function as traps for suspended sediment and excess flows are placed in pipe reservoir water temperatures would largely be a function of the depth from which water is drawn from the enlarged strawberry reservoir As explained in chapter IV during the june through september period when temperatures in strawberry reservoir would vary with depth water would come from warmer water layers about 5 to 15 percent of the years during 60 to 80 percent of the years water would come from deeper colder layers and during the remainder of the years from somewhere in between to compare alternatives estimated temperatures for the most prevalent expected conditions are tivenin givenin gi venin table 20 the recommended plan would provide the greatest temperature variation from present con editions ditions as explained above conditions in sixth water and syar reser doirs voirs would be similar in all alternatives hayes reservoir would be similar to monks hollow reservoir under the recommended plan and sixth water pumped storage alternative all reservoirs would be classified as eutrophic eutroph eutrophy ic because of high nutrient loadings however significant eutro autro phication plication phi cation problems are not expected because of water level fluctuations and short detention times particularly in the smaller reservoirs the operation of strawberry reservoir would not vary significantly with any of the five alternatives the maximum difference in reservoir surface elevation would be about 8 feet between alternatives all of the power alternatives would have limitations on reservoir value for recreation the extent of daily and seasonal changes in res ervoir water levels largely determines the value of the impoundment for recreation use the greater the fluctuation the lower the value for recreation A key factor in relating reservoir fluctuation to recrea reccea tion value is whether the daily water level changes occur on weekdays or on weekends when recreation use would be heaviest for the diamond fork power system a meaningful comparison of alternatives is limited be cause the plans have different features the downstream reservoir for the flow through alternatives would be operated as a regulating reser voir serving a demand which is predominantly for irrigation for this reason the reservoir would be drawn down considerably during the irrl gation period and recharged by the transbasin trans basin diversion during the non irrigation period in the winter the forebay and afterbay terbay af reservoirs for the pumped storage alternatives would fluctuate daily and weekly as the result of the daily movement of relatively large volumes of water between them this movement of water however would also eliminate the seasonal drawdown effect on the downstream reservoir under the fifth water pumped storage alternative weekend fluctuations of both reservoirs would be substantially less than what would occur on weekdays with the 99 |
| Identifier | http://cdm15999.contentdm.oclc.org/cdm/ref/collection/WesternWatersProject/id/3998 |
