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APPENDIX F. NOTES ON PULSE FLOW WORK,SHEET Oct. 1, 2007 • Purpose of worksheet This worksheet may be used to generally illustrate potential pulse flow release scenarios from the Environmental Account (EA) m Lake McConaughy on a daily time-step, assuming known system inflows, river gains, and how gains are anticipated to fluctuate with increases and decreases in river flow. Transit losses (or conveyance factors) for the NPPD and CNPPID canals and river are also assumed to be known and specified by the user. Two-day travel times are assumed between Lake McConaughy and the North Platte/South Platte confluence, and between the confluence/CNPPID diversion and Overton, whether via the Platte River or through the CNPPID system. Therefore, the worksheet is not intended to be a real-time simulation tool, but may be used to gain insight as to how to sequence EA releases with the Districts operations, given the above assumptions, to produce a pulse flow at the Platte River near Overton gage. General Description of EA Operations Utilizing Johnson Lake Rere2ulation and Intentional EA Bvpass at the CNPPID Diversion 1) EA releases are increased at the conservative ramp rate of 300 cfs per day from Lake McConaughy. No other releases of CNPPID or NPPD project water are planned for the non-irrigation season of water year 2008, due to operation in "conservation mode" to maximize storage in Lake McConaughy. No EA diversions are anticipated due to "conservation mode" operation by NPPD in 2008. Total flow at the North Platte River at North Platte gage should remain at or below the NWS flood-level of 1,980 cfs (stage = 5.7 ft). ? 2) Prior to the flow rate at the North Platte River gage reaching its maximum, EA water is delivered to Johnson Lake for temporary reregulation. 3) EA water is also bypassed at the CNPPID diversion to "wet up" the main Platte River channel. The maximum EA Bypass at the CNPPID diversion occurs when flows are greatest at the North Platte River gage. 4) As EA water bypassing the CNPPID diversion nears its peak value at the Overton gage, EA water previously routed to the Johnson Lake reregulating starage and CNPPID's "hydrocycling water" is released via the J-2 Return to time and match up with other water arriving at Overton. Following is a description of the worksheet computations and how to generally specify hydrocycling and EA operations: SOUTH PLATTE RIVER Column l: Shows estimated South Platte River inflow at the South Platte River at North Platte gage. Far reference, the 1995-2004 median March flow was 261 cfs. These cells should be adjusted using the anticipated South Platte River inflows anticipated prior to and during the EA pulse. NORTH PLATTE RIVER Column 2: EA release from Lake McConaughy. Entered manually, and should not increase more than 300 cfs/day for the initial pulse release test. There is no limit on the rate of daily decrease in the release. ? In the worksheet, the first day of EA release should be on "day 3" to minimize adjustment of other time- Water Year 2008 EA AOP 37 October 15, 2007