Services

Wastewater & Septic System Design

On-site wastewater systems for parcels without municipal sewer — percolation testing, soil evaluation, and septic system design in one coordinated scope.

What Wastewater & Septic System Design Covers

Not every parcel in the North Bay has access to a municipal sewer system — rural and semi-rural properties across Sonoma, Napa, and Marin Counties rely on individual on-site wastewater treatment systems (OWTS), commonly called septic systems, and a system that’s undersized or poorly sited for the soil fails expensively and can hold up a building permit indefinitely. CCE provides percolation testing, soil evaluation, and septic system design as one coordinated scope — distinct from the municipal sewer connection design covered under Wet Utility Design.

What’s Included

  • Percolation testing and soil evaluation to determine site suitability for an on-site wastewater system

  • Septic system design — conventional, alternative, and engineered systems matched to soil and site conditions

  • Design and permitting coordination with county Environmental Health / LAMP review

  • Septic system replacement and repair design for failing or undersized existing systems

  • Site evaluation for property transactions where an existing septic system’s capacity or condition needs review

  • Coordination with grading, drainage, and wet utility design so the septic system layout is consistent with the rest of the site plan

Wastewater & Septic System Design in Sonoma County and the North Bay

Sonoma County reviews individual septic systems under its Local Agency Management Program (LAMP) through Permit Sonoma, and Napa and Marin Counties apply their own separate standards and review processes through their respective environmental health departments. A design that doesn’t account for the specific reviewing agency’s soil and setback requirements is one of the more common reasons a septic permit stalls. CCE designs septic systems around the specific county’s actual LAMP or equivalent requirements, not a generic statewide standard.

Our Approach

Wastewater and septic system design is performed directly by Andrew Willis, P.E., who has worked in wastewater and soil-based system design since 2007. That experience — evaluating soils and siting systems that actually perform once installed, not just pass a plan check — shapes how CCE approaches percolation testing and septic design: sized to the actual site conditions, not a worst-case assumption borrowed from a different parcel.

Have a septic or on-site wastewater question on a North Bay parcel?

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