Lake Berryessa Resort Improvement District Wastewater Storage and Disposal Expansion
2014 / 2015
Approx. Contract Value:
This project expanded the storage and disposal facilities at the Lake Berryessa Resort wastewater treatment plant near Lake Berryessa in Napa County, CA. Two existing storage ponds were drained prior to mass grading that created three new ponds. Approximately 150,000 cubic yards of excavation to embankment was performed to create three ponds. At embankment alignments, excavation was performed to expose underlying bedrock upon which the embankments were founded.
Two new pump stations were installed to pump wastewater between the new ponds. Approximately 3,400 lf of 4" and 8" ductile iron pipe was installed for wastewater conveyance. An existing sprayfield pump station was modified by adding a new pump, valves, chlorine injection, flow meters, and automated controls. The existing electrical service was relocated and upgraded to include a new emergency generator.
An existing sprayfield disposal area was expanded and two new sprayfields were added with installation of 250 sprinklers fed by over 13,000 lf of galvanized steel pipe. A tailwater collection system was installed consisting of 2,400 lf of concrete-lined ditches and 1,200 lf of 12" PVC drain pipe. 300 lf of 24" RCP was installed as overflow relief piping between the new ponds.
Embankment slopes were seeded and covered with erosion control mats, and approximately 3,000 tons of aggregate base rock was placed as road surfacing.