Finance Committee Meeting 2007 - Laserfiche WebLink

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One method developed by the Committee to achieve its goals is the release of water from storage reservoirs above the target reach of St. Vrain Creek during winter months, for ultimate delivery to Union Reservoir and subsequent use. Earlier efforts resulted in satisfactory stream flows from Ralph Price • Reservoir (Button Rock Dam) down to the calling ditches near the Town of Lyons. However, at that point, it was not possible to continue the program as insufficient bypass facilities and measurement capabilities prevented delivery of the water beyond outdated diversion structures. The Project The Committee proposes to deliver water past the diversion structures of the Highland, Rough and Ready/Palmerton, and Oligarchy Ditches by installing FlumeGates manufactured by Rubicon Systems adjacent to those structures. These gates allow for both lower flow bypass control as well as accurate measurement of those flows, and will eliminate the primary obstacle to adequate streamflows lower on St. Vrain Creek. Due to the gates, water that has been released from storage that previously was diverted from the Creek below the Town of Lyons will be measurable and allowed to flow down the Creek. Once carried through the corridor, this water will either be diverted at the recently installed St. Vrain Creek Pump Station #1 (operated by the City of Longmont) or continue down the Creek for subsequent beneficial uses or to the South Platte River to meet delivery obligations. The FlumeGates typically normally are installed for control purposes only(either upstream level control or flow measurement only purposes). This project, using a moderately priced flow control and measurement device, will demonstrate a device that can be used on most streams in the State of Colorado where there is a need for low flow bypass capabilities at ditch diversion structures. In addition, since most devices of this type are for control of water in the summer irrigation season, the 410 need for a control device useable in typically freezing winter periods for low flow bypass is necessary. The Committee is working with Rubicon Systems to demonstrate the installation of either a heat strip or bubblers to ensure effective winter time operation of these control devices. These devices must uniquely be able to both measure and bypass flows while preserving upstream water levels for normal operation of the diversion structures. The Committee intends to install a FlumeGate at the Oligarchy Ditch headgate in winter 2008, which will provide the opportunity to move winter flows into an important reach of St. Vrain Creek. Water that would otherwise be diverted at the Oligarchy Headgate that is designated for delivery to Union Reservoir will be allowed to continue to flow down the Creek to be diverted at the Pump Station for delivery to Union Reservoir. While this will help move flows to an important reach of the Creek, the Committee believes it is necessary to install two additional FlumeGates higher in the Creek (at the Highland and Rough and Ready/Palmerton head gates) to ensure that flows move through the entire critical reach of the Creek and reach the lower section described above. The Committee has discussed the FlumeGate installations with the three ditch companies that own the subject diversion structures (Oligarch Ditch Company, Highland Ditch Company, Palmerton Ditch Company, and Rough & Ready Ditch Company). The companies support the installations, and the Committee intends to enter into a formal agreement with each company regarding the FlumeGates prior to proceeding with the installation. The Committee also is working with CWCB staff to discuss and develop legal mechanisms to protect the water provided under its program through the ISF Program. The Committee hopes to retain local Flood Protection•Water Project Planning and Financing•Stream and Lake Protection Water Supply Protection•Conservation Planning