Laserfiche WebLink
Final <br />Memorandum <br />To: Ray Alvarado and Ray Bennett <br />From: LRE, Erin Wilson <br />Subject: CRDSS Variable Efficiency Evaluation -Task 1.5, Compare StateMod Variable <br />Efficiency and Soil Moisture Accounting Historic Model Results to Previous <br />CRDSS Model Results and Historic Measurements <br />Date: November 5, 2001 <br />Introduction <br />The purpose of this task was to run the monthly Historic Yampa River Basin model with the <br />irrigation requirement file (*.ddc) created in Task 1.2 and the baseflows developed in Task 1.3. <br />The "Enhanced" simulation was performed with StateMod's variable efficiency and soil <br />moisture options set to "on" for the period 1909 through 1996. The results were compared to the <br />previous CRDSS Historic Yampa River Basin model results and historic measurements, <br />concentrating on the recent period from 1976 through 1996. <br />The Historic model data set is used to develop baseflows and calibrate parameters such are return <br />flows and reservoir operations. Its results allow the modeled hydrology, reservoir contents, and <br />diversions to be compared to recorded streamflows, reservoir end-of--month contents, and <br />diversions. <br />Approach <br />The following approach was followed for Task 1.5: <br />Run Historic Monthl~pa River Basin StateMod Model. The "Enhanced" monthly <br />Historic Yampa River Basin model was simulated with the variable efficiency and soil <br />moisture options "on" using the input files created in Task 1.2, the irrigation water <br />requirement file created in Task 1.2, and the baseflow file generated in Task 1.3. The <br />simulation log file was reviewed for errors and warnings, and no problems were identified. <br />2. Hand-check the variable efficiency calculation. The variable efficiency calculation was <br />hand-checked for two representative structures, 440694 Maybell Canal and 440509 Wilson <br />Ditch for the period 1976 through 1996. These results were also compared to the StateCU <br />results. The variable efficiency and soil moisture accounting methodologies were operating <br />VariableEff Taskl-5 1 of 17 November 5, 2001 <br />