Laserfiche WebLink
Districts' Fall Maintenance Activities - Kerkman described the Districts' fall maintenance <br />activities, to be done in two phases. These activities would limit the amount of water Central <br />will be able to divert at North Platte to about 1,400 cfs. The inspection of the Kingsley hydro <br />penstock would prevent any discharge from Lake McConaughy for about 24 hours. Maintenance <br />on Kingsley hydro will prevent releases from the hydro for about one week however water can be <br />released through the bypass tube. NPPD will be dewatering their siphon which will prevent them <br />from diverting water for about one month. NPPD will also be repairing a gate structure on the <br />Keystone diversion dam in October which will require Lake Ogallala to be lowered. Webster <br />said they would start decreasing Lake Ogallala in Sept. to dry-up NPPD's supply canal and <br />would divert S. Platte flows if available to compensate. RCC/EAC members had numerous <br />questions about flow requirements during that time and discussed how the District's should allow <br />some releases during that period, if necessary. Kerkman said instream flow requirements were <br />junior to most other storage rights so didn't foresee any problems in meeting those needs. He <br />indicated that Lake Ogallala will be drawn down but river gates will still be operational. How <br />the maintenance activities might affect the ability to release EA water in the fall (e.g., pulse flow <br />test) was discussed. Kerkman indicated that if EA releases were requested, the water could be <br />sent down the North Platte River. <br />EA Pulse Flow Test <br />Whitmore explained the Preproposal Discussion Draft for a possible pulse flow test using EA <br />releases and asked for input from the group. She indicated that the operational scenario <br />described in the draft was developed by Tim Randle using an unsteady flow model to predict <br />how a pulse would move through the system. One purpose of the test would be to test how <br />accurate the model predictions were. Various concerns were voiced including: <br />- Who will be accountable for damages that may occur? <br />There is not enough time to get monitoring in place which is described as the number one <br />goal in the draft proposal. <br />- Should consider flood stage in the North Platte River at North Platte. <br />- Doing this test is premature as there are too many unknowns right now. <br />- The scale of the test is too small to really see any effects. <br />- There is no ramping included in the flow regime described in the draft proposal. <br />- The test could violate long-standing limits on operations. We should be very cautious <br />about doing something outside current operations, established through long-term <br />management of the river and canal system. <br />- Losses in the predicted flow amounts, described in the draft proposal, could result from <br />bank storage and river spreading. <br />After the discussion, Whitmore indicated that even though there were concerns and the potential <br />effects were questionable, it appeared there was general support for "testing" the ability of the <br />system, using the EA, to route water through the system to create/augment a pulse flow at some <br />point in the future. Several suggestions for the draft proposal were provided including: <br />- Incorporate acceptable ramping into the release scenario. <br />2