On-Site Septic Facility

Legacy Engineering provides full-service On-Site Septic Facility (OSSF) design and permitting for residential, commercial, and development projects that are not served by a public sewer system. Our team handles everything from site evaluation through final approval, ensuring your system is properly sized, code-compliant, and built to perform long-term.

What We Provide

Site & Soil Evaluation

We evaluate your property to determine feasibility and system type by analyzing:

• Soil composition and absorption capability

• Groundwater depth and restrictive layers

• Available area for primary and reserve drain fields

• Topography and setback compliance

System Design

We design septic systems tailored to your site and usage needs, including:

• Conventional and alternative systems

• Low-pressure dosing (LPD) systems

• Aerobic treatment units (ATUs)

• Drip irrigation systems

• Commercial and high-flow systems

Each system is engineered to meet local authority requirements and long-term performance standards.

Permitting & Regulatory Coordination

We prepare and submit all required documentation for approval through the appropriate authority, including:

• Site plans

• Soil test reports

• Engineer-stamped design plans

• Compliance documentation

We coordinate directly with regulators and installers to minimize delays and void costly redesigns.

Construction Support

We provide technical support during installation to ensure:

• Correct system placement

• Proper elevations and slopes

• Pressure testing where required

• Final inspection readiness

System Troubleshooting & Upgrades

If you already have an OSSF, we can assist with:

• System failures

• Site changes

• Property expansions

• Capacity upgrades

We also assist with replacement system designs when existing systems are no longer functioning or compliant.

Who This Service Is For

• Rural residential properties

• Commercial buildings without sewer access

• Subdivisions requiring individual or shared systems

• Developers evaluating land feasibility

• Property owners needing system upgrades or repairs

Why Choose Legacy Engineering

• Engineer-designed systems (not cookie-cutter layouts)

• Local regulatory knowledge

• Fast permitting and responsive coordination

• Long-term reliability and compliance built into every design

• Clear, upfront communication throughout the process

Common Client Questions

Do I need an engineer for a septic system?

Not always — but engineered systems are often required for commercial properties, alternative systems, challenging soils, and subdivision developments.

Can you help if my system is failing?

Yes. We specialize in diagnosing problems and retrofitting non-compliant or failing systems.

Do commercial systems require extra land area?

Yes. Commercial systems have higher wastewater loading rates and often require reserve area and enhanced treatment depending on local regulations.