Jefferson County septic permits and inspection rules

Permit requirements

New installations, repairs, and expansions of onsite wastewater treatment systems in Jefferson County require an OWTS permit from Jefferson County Public Health before work begins. Applications include a system design, soils information, and a site plan, and complex sites need a Colorado professional engineer.

What triggers an inspection

The county's Use Permit program is the main inspection trigger: any property sale involving a septic system installed more than five years before the sale date requires an inspection by a county-certified inspector. Repairs, expansions, and complaints can also bring the system under county review.

Transfer of title rules

Jefferson County requires a Use Permit before the sale of a property with a septic system installed more than five years prior to the sale. A county-certified inspector evaluates the system, the tank is typically pumped as part of the inspection, and the permit is generally valid for six months or until the title transfers. Confirm current fees and validity with the county; the filing fee has been about 75 dollars.

Required pumping frequency

Jefferson County does not set a fixed statutory pumping interval for every home. Most Front Range households need pumping every three to five years, and the Use Permit inspection at sale usually includes a pump-out, which resets the clock.

• Pump when combined scum and sludge approach a quarter of tank volume
• Garbage disposals and high occupancy shorten the interval

Setback rules

Jefferson County enforces at least the Colorado Regulation 43 minimums: 100 feet from a well to the soil treatment area, 50 feet from a well to the septic tank, 50 feet from surface water, 10 feet from property lines, and 5 feet from a dwelling to the tank. Mountain lots and wells can push these further, so confirm before any excavation.

Soil and percolation testing

New and replacement systems need a soil evaluation with profile test pits, and percolation testing where used, performed by a qualified professional. Steep slopes, shallow bedrock, and high groundwater common in Jefferson County foothills frequently require an engineered design.