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needs of the plan for augmentation. Smith Geotechnical on behalf of OAC has talked with the Office <br />of the State Engineer. regarding the construction of a non jurisdictional dam. Anon jurisdictional <br />dam has a storage capacity less than 100 acre-ft, a spillway embankment height less than 10 ft, and a <br />maximum water surface area less than 20 acres. The Office of the State Engineer conveyed that a <br />non jurisdictional dam could be constructed however the State may require that a hazard study be <br />completed to show the potential hazard the dam may have on the public. Based on the size and <br />location of the proposed reservoir Smith Geotechnical feels that the proposed reservoir will have low <br />to no hazard potential. <br />The proposed general location of the storage reservoir site is near the end of the Ogilvy ditch system. <br />Figure 2 shows the proposed general location of the reservoir site. The proposed general layout of <br />the reservoir allows for the reservoir to be constructed in place of a small detention reservoir that was <br />recently constructed by OLIC for ditch operations. The proposed general reservoir layout is shown <br />in Figure 3. <br />A range of alternatives were considered for the reservoir including: 1) A 50-Acre-Ft Reservoir with <br />an HDPE liner, 2) A 50 Acre-Ft Reservoir with a clay liner, 3) A 50 Acre-Ft Reservoir with an <br />HDPE liner on the embankments and a clay liner along the base, and 4) A 100 Acre-Ft Reservoir <br />with an HDPE liner. To facilitate the reservoir site assessment, Smith Geotechnical performed soils <br />investigations at the proposed reservoir site. A copy of the geotechnical report is enclosed in <br />Appendix G. <br />8.4.1 Reservoir Alternative 1- SO Acre-Ft Reservoir with an HDPE Liner <br />Alternative 1 is for the construction of a new ~50 acre-ft reservoir near the end of the Ogilvy Ditch <br />system. The new reservoir will use the existing ditch outlet that was installed on the ditch to feed the <br />small detention reservoir built by the OLIO. The side slopes for the new reservoir will be set at <br />3H:1 V for the upstream and downstream slopes. A geotechnical investigation of the reservoir site <br />found the site soils to be granular and fairly permeable; due to the granular nature of the soils the <br />reservoir will require an impermeable liner. For alternative 1 the reservoir liner was assumed to be <br />an HDPE liner, the HDPE liner has the benefit of being both resistant to UV desiccation and suitable <br />for protection against wind/wave erosion. One negative to the HDPE liner is that the liner can be <br />damaged if gas pressures build up below the liner and cause the liner to deform. <br />The estimated total project cost for this alternative is $ 460,000 as show in Table 5. A complete <br />breakdown of the work proposed and expected costs are included in Table 5. <br />Feasibility Study of the Ogilvy Augmentation Company Page 8 <br />Well Augmentation Project <br />