Tinemaha Dam

In 2020 LADWP, working with the Department Safety of Dams, proposed a geotechnical investigation in the vicinity of the Tinemaha Dam near Big Pine, CA. The Tinemaha reservoir is part of the Los Angeles Owens River Aqueduct system which supplies over 80% of the water to Los Angeles. Built in the 1920s, there were several issues with the dam that will eventually require replacement. The geotechnical work was needed to investigate the geology and hydrogeology surrounding the dam and reservoir and will be used to inform how the dam will be replaced as a future project. The investigation involved borings, seismic cone penetration testing and monitoring well installations.

Highlights:

• 16 Seismic CPTs and 20 additional CPTs up to 110ft bgs
• Multiple dissipation tests conducted at each location
• 4 Stainless steel wells installed to 70ft
• 2 PVC wells totalling 235ft
• Continuous soil sampling using sonic drilling methods
• Contract value of $500k

Download the full project profile in PDF