Due to development downstream since 1975 when the dam was constructed, and the potential impacts of a failure, the dam was reclassified as a high hazard structure and no longer complies with state and NRCS dam safety and performance criteria. The proposed rehabilitation is intended to to maintain flood control benefits, augment water supply, and meet state and NRCS requirements.
Schnabel’s feasibility report—the first step in development of a supplemental watershed plan and environmental assessment to address rehabilitation—revealed that the auxiliary spillway did not meet capacity, stability, and integrity criteria. Schnabel developed design alternatives that addressed both dam safety deficiencies and raised the pool to increase water supply, per the city’s request.
The preferred alternative includes a fuse gate system in the auxiliary spillway, addresses increased water supply storage, and raises the embankment.
- Construction Management
- Conservation Planning
- Hydrology and Hydraulics
- Geotechnical Analysis