Septic Design & Consulting in Longview

Septic Design & Consulting Experts Serving Longview

When you need septic system planning in Longview, WA, McNair Septic Design & Consulting is your trusted local partner. We provide comprehensive services including site and soil evaluations, perc testing, and complete septic system designs. Our team works with homeowners and builders across Longview, Kelso, Castle Rock, and the greater Cowlitz County area, ensuring systems are efficient, reliable, and fully compliant with county regulations.

With three generations of experience, we know how to navigate every detail of the design and permitting process. Whether you’re building a new home or upgrading an existing property, our septic design and consulting services help you avoid delays, reduce costs, and install a system that will serve your property for decades. We handle the paperwork, communicate with county officials, and design for long-term performance.

At McNair Septic, we don’t offer one-size-fits-all designs. Instead, we tailor every system to your property’s unique features—whether that requires a conventional gravity system, a pressure distribution system, or a more advanced solution like a sand filter or mound system. By working with us, you’ll gain clear communication, cost-conscious recommendations, and designs approved faster than most competitors.

From initial planning to final as-builts, we’re here to make septic design simple. Longview homeowners choose McNair Septic because we combine decades of local knowledge with modern, property-specific solutions. Let us guide you through the process with confidence and expertise.