Perc and Soil Testing, Northern California

Shasta County requires a passing perc test before any septic permit can be issued. Lee One Construction performs professional percolation and soil testing and handles the permit application that follows.

Available 24 hours a day. Call 530-227-3478

A Perc Test Is the First Step Every Septic Project Requires

Lee One Construction is a licensed excavation and septic contractor serving Anderson, Redding, and communities across Northern California since 2020, with 25 years of hands-on field experience. A percolation test, commonly called a perc test, measures how quickly water drains through the soil on a given parcel. Shasta County Environmental Health requires a passing perc test before they will approve any septic system permit. Without it, a property cannot legally install a new system and cannot move forward with development. The test is not optional, and the results determine the entire system design.

This is the most misunderstood part of the process. A failing result does not automatically mean a lot is unbuildable. It means the soil in the tested area cannot support a conventional septic field at that location. In some cases, the lot can be retested in a different area or the system design can shift to an alternative type, such as a mound system or pressure-dosed field, that the county will approve. The risk of a failed result grows sharply when testing is done by someone who does not also handle the permit application, because they have no incentive to identify the best testable area or document results in a way that supports the design that follows. Incomplete or poorly executed testing costs weeks of project time and delays the permit that cannot start until results are accepted.

How Lee One Construction Performs a Perc Test

The perc and soil testing process begins well before any equipment arrives on site. We review the parcel's soil survey data, identify candidate test areas, and coordinate the testing schedule with Shasta County Environmental Health so results are documented in the format the county requires. A test that produces results the county won't accept is time and money spent for nothing. We plan every step to avoid that outcome before work starts.

Site Evaluation and Area Selection

We walk the lot and identify the best candidate areas for testing based on soil survey data, slope, and the planned system footprint before a single test hole is dug.

Test Hole Excavation

We excavate test holes to the depth specified by Shasta County, typically between 24 and 72 inches, using equipment sized for the site conditions.

Pre-Saturation Period

We pre-saturate each hole according to county protocol, allowing water to soak in over the required period so the measurement reflects worst-case soil conditions, not a dry-day result.

Timed Water Absorption Measurement

We fill each hole to a set level and record the drop in water level at timed intervals. This is the percolation rate that determines whether the lot passes or fails.

Soil Profile Assessment

Alongside the perc test, we log the soil profile, identifying clay layers, restrictive horizons, seasonal high water tables, and rock that would affect system design.

Documentation and County Submission

We prepare a complete test report in the format Shasta County Environmental Health requires and submit it on your behalf, so the results are accepted without back-and-forth.

Perc Results Feed Directly into Your Septic Permit Application

A perc test produces two critical outputs: the percolation rate, which is how fast water moves through the soil, and the soil profile, which shows what the ground layers look like at depth. Together, these determine the system type the county will approve, the minimum leach field size required, and the setback distances that the permit application must document. A contractor who hands you a test report and walks away has left you with data you cannot use without another professional to interpret it. The translation of perc results into a permitted system design is where most projects stall when two separate companies are involved.

When we conduct the perc test, we are already designing the system in our heads. We know which areas tested well, what the soil profile shows at depth, and how Shasta County's current reviewers expect the data to be presented. That means the permit application we submit reflects the test results exactly. No interpretation errors, no missing documentation, no requests for clarification that push your approval date back by three weeks. We have submitted permit applications through Shasta County Environmental Health enough times to know what gets approved on the first submission and what doesn't.

If your perc test produces a passing result, the next step is the permit application and system design. Lee One Construction manages both, from the first test hole to the stamped permit in your hands. Learn more about how we handle the full permit application and design process on our Septic System Permit Application and Design page.

Common Questions About Perc and Soil Testing in Northern California

Schedule Your Perc Test Across Shasta County and Northern California

Lee One Construction performs perc and soil testing across Anderson, Redding, Shasta County, and surrounding Northern California communities, seven days a week, including weekends. We handle the full process from the first test hole to permit submission, so your project moves forward without waiting on multiple contractors. CSLB #1063228.

Call 530-227-3478 now to schedule your perc test or ask about combining testing with a full septic permit application. No appointment needed.