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<br />000428 <br /> <br />. <br /> <br />. <br /> <br />the modified version and help develop additions and modifications necessary to <br />have an acceptable tool. The review of the NPRSM began by discussing the <br />approach used to develop this model, for example; this OPSTUDY program <br />contains 3 computational subroutines instead of one. They were broken into 1) <br />natural flow and storage flow, 2) reservoir operation, and 3) ownership. The <br />sequence they run is OPRES which operates the reservoirs based on demand <br />working upstream, O~N~'LOW sorts based on water rights and ownership, and OPSOA <br />which balances storage ownership accounts. The study team discussed how the <br />model checked between the three computational subroutines to obtain a balance <br />between total reservoir storage and storage ownership water accounted for in <br />the reservoirs a It was noted that storage and ownership do not balance when <br />there is excess water in the system and the program iterates from the <br />ownership routine back to the reservoir storage routine to make additional <br />releases from storage until there is a balance. This iterative process is <br />used to spill excess water on downstream. As discussion continued on the <br />model's computational steps, it was explained that if you start at the state <br />line the program adds up water use demands (modified model is using historic <br />diversion with some adjustments in dry years as demands) and accounts for <br />gains as it works upstream. After the program has made computations up to <br />Serninoe reservoir for the OPRES subroutine and all demands are met, it then <br />computes how much of the releases are natural flow and storage flow in the <br />OPNFLOW subroutine. Knowing the storage flow release the program then <br />computes the new ownership accounts in the BOA subroutine and checks the total <br />reservoir storage with total water in the ownership accounts. If the <br />ownerships are full and there is excess water in storage, a new demand is <br />created to release the water from storage so the storage and ownership <br />balance. It takes several iterations to balance because reservoir evaporation <br />continues to change with each iteration. The question was asked if a priority <br />system was built into the model. The answer is yes but it needs a good r~view <br />to make sure it is right. <br /> <br />The question was asked if the model ran on a pc. Rich Kern with Nebraska <br />Natural Resources commission said he had worked on converting it to a PC and <br />can provide input, output, and source code but no documentation has been <br />written. He noted there weren't a lot of changes to convert it from VAX <br />FORTRAN 77. <br /> <br />Based on the discussion copcerning the operation of the NPRSM, the following <br />questions where raised, some required further checking of the model while <br />others highlighted model input decision that need to be made. <br /> <br />1. Does model use Pan Evaporation rates or Lake Evaporation rates when <br />computing Reservoir Evaporation? <br /> <br />2. Will the model use preliminary or final monthly runoff records as <br />inflows, and will they be lagged? <br /> <br />3. What are the computations made to computed gains and losses, and for <br />what reaches of river are they made? <br /> <br />4. Does the model provide flows at different sections of the river, such as <br />those sections which would pertain to endangered species? <br />