Arkansas - Ark Headwater Diversion Structure Improvement_Water Activity Summary

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is operated by the Colorado Department of Corrections; 3) the Hydraulic Diversion Structure at Canon City; and, 4) the Oil Creek diversion structure at Canon City. Each ofthese diversion structures currently provides dangers for recreational boaters at certain flows. The design drawings, modeling and design reports would provide the background necessary to ultimately reconstruct these diversions in a manner that improve boaters' recreational experience. Water-based recreation within the Arkansas River basin is important to the economy of the Arkansas River basin and the entire state of Colorado. As such, any improvements to river access and the recreational experience of visitors will improve non-consumptive uses of water in the Arkansas River basin. In addition, this project could result in improved efficiency of current diversions from the Arkansas River for consumptive uses. Discussion: The work will address issues with four different diversion structures. With regard to the Granite Diversion Structure at Granite, this area is unpassable to rafts and kayaks year-round and if accidentally boated under the current conditions, it could result in fatalities. The second structure, the Helena Diversion structure is extremely dangerous due to portions of the structure that have shifted over time that has resulted in a dangerous spillway. The third diversion structure is the Hydraulic Diversion Structure at Canon City just upstream from the main takeout at Canon City and this structure causes the reach to be unpassable to rafts and kayaks during low water time periods. Finally, the Oil Creek Diversion Structure at Canon City currently has exposed metal and creates a safety issue at this location. The Applicant has indicated that these structures also prevent aquatic species from passing upstream and downstream of the structures at certain time periods. This fact was not documented, but improvement of these structures could have incidental benefits to the Arkansas River fish passage. The Scope of work includes four tasks. Task 1 involves base mapping and surveying of three of the structures. The Granite diversion structure has already been surveyed by CH2M Hill. Task 2 will be to create one draft design plan for each structure. Task 3 will be to complete HEC-RAS computer flood modeling for each diversion site. There will be no negative impact to the regulatory flood at each site. It is represented that the model runs will show that the diversion capability will be maintained or improved and that there will be no reduction in flood carrying capacity at each site. Task 4 will be to create an associated design report for each diversion describing improvements, requirements for implementation, and cost estimates. Issues/Additional Needs: 1. The Application does not reference the specific SWSI water supply needs that this application would address. In addition, the application indicates that this application could address the safe passage aquatic species both up and down the river corridor during critical time periods such as the spawning season, but the application does not reference any study or information demonstrating that this is an issue. 2. The application does not provide any infonnation regarding how the potential design improvements would be implemented and funded if this grant is approved. Without a plausible plan for implementation of potential design improvement there is little justification for investing state funding for a project that may never be implemented. The applicant must provide a description of how future work would be accomplished and funded and the likely timeframe to implement future work. 3. The Application did not appear to provide a schedule for this work, but it was merely a problem with the printing. A copy of the anticipated schedule is attached to this summary. - 2 -