C150094 Application (2) - Laserfiche WebLink

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5. Embankment Section, Internal Drains, and Riprap. Alternative embankment sections will be developed based upon the availability of borrow material. Alternatives will be evaluated for the embankment cross sections using earth fill,rock fill and possibly roller- compacted concrete. The embankments will be designed with internal drainage features to control the phreatic surface in the embankment and prevent piping of fine-grained soils through the embankment or foundation soils by seepage forces. Riprap will be provided for slope protection and potentially as a lining in the spillway and energy dissipation structures. Embankment sections will be developed to provide adequate stability for steady-state,rapid drawdown and pseudostatic earthquake loading conditions. Embankment slopes will be determined based upon published literature. Formal stability analysis using a limit equilibrium computer program will be conducted during final design. Alternatives will be evaluated using"Factors for Planning Studies"in Appendix B of the CWCB guidelines. Quantities will be estimated and unit costs will be developed to provide costs of each alternative. This information will be combined with data on the project yields, environmental impacts, financing, regulatory requirements, and any special technical problems to evaluate the alternatives. Study Report(s) A study report or reports will be prepared summarizing the findings for items 1 through 9 shown on Table 2. The final report will also present an updated outline for a water management plan on the La Plata River, and an evaluation of the need for a hydrologic model(s) of the La Plata River. The fieldwork discussed herein and the study report preparation will be conducted under the supervision of a registered professional engineer. Estimated Costs - A breakdown of all estimated costs by major category associated with work for the Red Mesa Ward Reservoir enlargement is included in Table 1. A comprehensive breakdown of the costs associated with each work task is included in Table 2. Total estimated costs for work at the Red Mesa Ward Reservoir are $135,114. The work required to accomplish the outlined data collection and alternatives analysis cannot be absolutely defined in advance and the final costs may differ somewhat from those estimated. However, the maximum estimated fee would not be exceeded without prior written approval. Schedule WWE proposes to initiate the investigation promptly after being given notice to proceed. WWE will report to the La Plata Water Conservancy District(LPWCD) frequently and keep the CWCB staff informed of preliminary information as it becomes available during 9