Perc Tests & Septic Permits in Santa Barbara & SLO Counties
New septic systems and most replacements start with soil testing and a county OWTS permit. Here is how the process works in both counties we serve — in plain language.
- Licensed C-42 contractor — license shown in writing
- County-permitted installations & replacements
- Free on-site evaluation before you commit
What a perc test is
A percolation (“perc”) test measures how quickly your soil absorbs water. Holes are dug in the area proposed for the drainfield, prepared and saturated, then timed as the water level drops. Combined with soil profile pits — which reveal layers, hardpan, and the depth to groundwater or bedrock — the results decide what kind of system your lot can support and how large the drainfield must be.
Perc results are the fork in the road for cost: good-draining soil usually allows a conventional system; poor results can mean a larger field, a mound or pressure-distribution design, or advanced treatment. That is why serious quotes wait for perc data.
The general permit process
Site evaluation
Property review: proposed field location, setbacks from wells, water lines, structures and property lines, plus the required reserve area for a future replacement field.
Soil & perc testing
Test pits and percolation testing, documented for the county application. Wet-season testing or groundwater data may be required in some areas.
Design & application
A system design matched to the soil data and home size is submitted to the county’s Onsite Wastewater Treatment System (OWTS) program for review.
Permit, install, inspect
Once the permit issues, a licensed contractor installs the system; the county inspects at required stages before the system is covered and approved for use.
Santa Barbara County
In Santa Barbara County, septic systems are regulated through the county’s Environmental Health Services under its OWTS program, which implements California’s state OWTS policy along with local requirements. New systems, replacements and significant repairs need county review and permitting, and areas near impaired water bodies or with known groundwater concerns can carry additional requirements. Our Santa Maria, Orcutt, Lompoc and Santa Ynez Valley work all falls under this program.
San Luis Obispo County
San Luis Obispo County also administers septic permitting through its Environmental Health Services OWTS program, with local rules layered on the state framework. Parts of the county — including areas over the Paso Robles groundwater basin and Los Osos-adjacent zones — have their own histories and requirements; Nipomo, Arroyo Grande, Atascadero and Templeton properties are reviewed with those local conditions in mind.
Deliberately general: permit fees, exact setback tables and ordinance specifics change and vary by parcel — we don’t publish numbers that could be wrong for your lot. Your quote process includes confirming the current county requirements for your specific property before work is designed or priced.
Who does what
Your contractor coordinates testing, design submittal and inspections as part of the job — you should not have to shepherd paperwork between offices. What the county requires of you directly (signatures, access for inspectors, recording documents where applicable) is explained before the application goes in. Work performed must be by a contractor holding a CSLB C-42 Sanitation System license, or a C-36 plumbing or Class A engineering license where the work falls within that license’s scope.
Get a free, no-pressure septic quote
Tell us what’s going on with your system. A licensed local septic contractor reviews your request, and their license is verified and shown to you in writing before any work starts. No obligation.
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