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I I I I I I I I I I I I I I I I I I I _n-.i__ CHAPTER V PLAN OF DEVELOPMENT A. Physical Plan As a part of the Colorado Dam Safety program, Ish Reservoir was inspected by the State Engineer's Office. Seepage was observed below the southeast dam adja- cent to Boulder County Road 3 (North 115th Street). To correct this problem the Ish Reservoir Company removed the existing rip-rap on the upstream side of the dam, excavated a trench, filled the trench with selected material, compacted to 95% proctor density, and replaced the rip-rap, all according to the plans and specifications shown in Appendix D, page D-2. Boulder County then rebuilt the road. Improvements were also required on the northwest dam as described in the copy of the letter from the Office of the State Engineer, shown in Appendix A, page A-24. It was agreed that the seepage problem noted in the inspection report could be resolved by the installation of a toe drain. The approved design for the toe drain is included in the plans and specifications in Appendix D, page D-2. The financial strain on the ditch company prevented the completion of both projects at the same time, so the toe drain construction was delayed. Additionally, it was determined that the length of the toe-drain needed to be extended to approximately 4000 feet, as opposed to the approximately 680 feet originally proposed in the design. The State Engineer's Office will restrict storage if the toe drain is not constructed, thus affecting both irrigation and fish and recreation uses. B. Geologic Investigations Test holes were drilled at both the southeast and northwest dams. The boring logs are shown in Appendix D, page D-8, as a part of the specifications for the "Ish Reservoir - 1985 Proposed Improvements". -1'- I . iJt