Showing significant signs of age, the spillway at Lake Ogletree Dam was in dire need of short-term and long-term fixes so it could continue to help provide the citizens of Auburn reliable, safe drinking water. The city’s Water Works Board hired Schnabel to develop alternatives for temporary repairs that would prolong the service life of the spillway, and later called on us to develop a more permanent solution.

Created in the early 1940s, the 48-foot-high Lake Ogletree Dam impounds a 300-acre reservoir. By 2009 the auxiliary spillway had greatly deteriorated. Seepage issues associated with voids beneath the concrete slabs and open joints between slabs had become apparent. To help remedy these deficiencies, we provided construction documents for a grouting and joint-sealing operation, as well as construction administration and observation services.

The temporary repair measures gave the city time to plan for the future. The city wanted a more-permanent solution for the high-hazard dam’s spillway that would also increase the reservoir’s drinking water storage capacity. We designed a 218-foot-wide labyrinth-crested concrete chute spillway and raised the crest of the new structure by six inches, which enabled the city to increase water supply volume by 50 million gallons. Construction on the spillway began in November 2015 and was completed two years later.

© Propex GeoSolutions

Related Projects