Davis Lift Station Design

The City of Davis Lift Station Design project included upgrades to existing Sewer Lift Stations (SLS) #1 and #3 and relocation of another SLS to the existing City corporation yard. The SLS’s include:

• new wet wells,
• valve vaults,
• control panels,
• odor control units, and
• hot mix asphalt pavement improvements.

Blackburn Consulting completed subsurface exploration and laboratory testing, and prepared geotechnical reports for each lift station that included recommendations for:

• foundation subgrade support,
• buoyancy resistance,
• pipe loading and deflection evaluation,
• excavation support and backfill,
• site grading, and
• pavement design.

Our site reconnaissance revealed the evidence of long-term settlement issues of the existing pavement and structures at SLS #1.  We completed subsurface exploration to determine the cause of the settlement and discovered over 20 feet of poorly compacted fill presumably placed during construction of the original pump station. We provided several mitigation alternatives to avoid potential damage to the new, proposed SLS improvements including:

• overexcavation and re-compaction of the fill,
• installation of helical anchors to support the existing structures, or
• installation of rammed aggregate piers to support the structures and pavement.