An interior berm within the 215,000 square foot existing reservoir was removed and replaced with a vertical shotcrete wall supported by 40,000ft. of soil anchors.


  • Excavation Volume: ~78,500 cubic yards
  • Shotcrete Fill Anchors: 1,020 ea x ~30’ = 30,600 Ft
  • Shotcrete Till Anchors: 481 ea x ~20’ = 10,200 Ft
  • Shotcrete Shoring Wall Area: 49,000 sq. feet
  • Seismic Shotcrete Slab/Beam: 7,700 sq. feet


This fast-track project required critical deadlines to be met.

Other elements of the project included a 65”-diameter emergency drain-down pipe from the center of the reservoir to an outflow chamber.

A reinforced structural shotcrete slab/beam integrating the floor and perimeter wall over an old rock quarry was required to transfer seismic loads and to prevent water intrusion.

SWC met all of the milestones, despite site congestion and very difficult drilling conditions through fill materials.


Little Mountain Reservoir Little Mountain Reservoir Little Mountain Reservoir