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SECTIONFOUR Formulation of Alternatives <br /> 4-1 <br />4. Section 4 FOUR Formulation of Alternatives <br />4.1 OVERVIEW <br />Several nonstructural and structural alternatives were considered to meet the Project’s <br />needs. These alternatives also included a No Action alternative. The No Action alternative for <br />the Project was deemed not viable due to the loss of the system operation. <br />The spillway alternatives ranged from complete replacement of the spillway to <br />rehabilitating the existing spillway in place. It was decided that rehabilitating the spillway in <br />place was acceptable and would provide SMRC a structure that would safely pass the required <br />design flood for the lowest cost. <br />Several alternatives were reviewed to control the seepage from the embankment that <br />included grouting the left abutment, grouting the dam embankment, and constructing an internal <br />seepage collection system along the downstream dam face. It was determined that it would not <br />be cost effective to grout the left abutment and embankment due to the uncertainty that the <br />grouting program would reduce the seepage to an acceptable level. The internal seepage <br />collection system was selected as the preferred alternative based on technical merit and cost. <br />4.2 NO ACTION <br />Potential failure of the embankment could occur in the future due to the present condition <br />of the concrete spillway and the uncontrolled seepage from the embankment. If the embankment <br />fails, the irrigation water will not be delivered to the shareholders along with the high probability <br />of the loss of life downstream of the dam. <br />The Continental Reservoir provides water to the Santa Maria Siphon and canal system <br />conveys which in turn conveys water to the Santa Maria Reservoir. Santa Maria Reservoir stores <br />irrigation water and also stores water for the Rio Grande Compact, the San Luis Valley Water <br />Conservancy District, Colorado Division of Wildlife (CDOW) a.k.a. Colorado Parks and <br />Wildlife, and Trans-Mountain diversion. If Continental Dam fails, these water deliveries will be <br />disrupted and could become a legal issue. The No Action alternative was not judged to be a <br />viable alternative and was not considered further.