OCR Text |
Show have indicated that seepages and accretion flows below Unit structures would contribute water to the channels of all the streams to be dewatered and in some cases the recommended minimum flows would be met or exceeded a relatively short distance below the Unit feature. These situations will be described and documented below. The effect of the planned fishery bypasses on the recommended fishery requirements, at the points of diversion and impoundment, is illustrated in Table C- 4. It is apparent that under the proposed plan of operation there would be an average annual unsatisfied fishery demand of about 20,000 acre- feet of water. In interpreting this table, it must be remembered that stream gains below Unit features have not been included and the figures presented cannot validly be applied to downstream locations, but only to the reach immediately downstream from the Strawberry Aqueduct Diversion. Streamflows Under Unit Conditions In order to graphically illustrate the effects of the presently planned Bonneville Unit on streams within the Unit area, several figures and tables have been prepared. Three types of conditions are depicted for the Uinta Basin streams. Upper and Lower Provo River, Sixth Water Creek, Diamond Fork Creek, and the Spanish Fork River. These conditions are: ( 1) the winter flow situation, ( 2) the early irrigation or high runoff period, and ( 3) the late irrigation or low runoff period. The average streamflow conditions depicted for Uinta Basin streams are based upon the historical flow records for the 1920- 60 period. This 40- year period is sufficiently long to represent typical hydrological conditions. For the Provo River, the record for the year 1956 represented a near average set of conditions and data for this year were used to prepare the illustrations presented. Schematic flow diagrams of the Uinta Basin streams affected by diversion or impoundment are presented in Figures C- l through C- 3. Flows within the capacity of the Strawberry Aqueduct intake structures and not required for downstream rights would be diverted into the Aqueduct for conveyance to Strawberry Reservoir. 291 |