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State guide

Septic companies in Wyoming

Wyoming does the opposite of what you would expect: the state keeps the septic permit in only a handful of counties and hands the rest to the counties themselves, under a statute written to do exactly that. So the first question here is not what the rule says, it is which office holds your county's authority. This guide covers that split, the size of system the state general permit covers, the engineer and sanitarian sign-offs, and the Cheyenne quirk that catches people out.

Companies
31
Counties
13
With Google reviews
17

Who Regulates Septic Systems in Wyoming

Sources: Wyoming Department of Environmental Quality; Teton County, Wyoming. Checked 2026-09-21.

Wyoming hands most of this work to the counties. The state environment department keeps the permit in a short list of counties and delegates everywhere else, under a statute written for that purpose. So the first thing to establish is which office holds the authority where you live.

DEQ authorises permits to construct for small wastewater facilities located in Campbell, for commercial systems only, plus Carbon, Niobrara, Platte and Weston counties, where DEQ is the permitting authority opens in a new tab. For other jurisdictions the permitting authority may require different forms or additional information opens in a new tab. That leaves most of the state with a local office rather than a state one.

The delegation is statutory rather than informal. Wyoming statute 35-11-304 provides that, to the extent requested, authority to enforce and administer the relevant permit provisions shall be delegated to qualifying municipalities, water and sewer districts or counties opens in a new tab, and Teton County's small wastewater regulations are an integral component of the delegation agreement in effect with its Board of County Commissioners opens in a new tab. Where a county has taken the authority, the county's rules are the ones that bind you.

Licenses and What to Check Before You Hire

Sources: Teton County, Wyoming; Wyoming Department of Environmental Quality. Checked 2026-09-21.

Wyoming's rules lean on an engineer and a sanitarian rather than on a septic trade licence. In Teton County the design engineer must certify, before or coinciding with the Sanitarian's final inspection, that the installation conforms to the approved design opens in a new tab. Two sign-offs, one from your side of the table and one from the county's.

The general permit also tells you the size of job it covers, which is worth checking before a designer starts. It covers the installation, repair or replacement of individual or commercial sewage disposal systems that treat less than 2,000 gallons of domestic sewage per day opens in a new tab. Above that figure you are into a different permit and a longer process.

The tank itself is not a free choice either. DEQ publishes a list of approved septic tank models and providers to help you select your tank opens in a new tab, so ask whether the tank in your quote is on it. We hold no Wyoming register of our own, so no listing on this site carries a verified credential for this state.

Permits, Inspections and Selling a Home

Sources: Wyoming Department of Environmental Quality; Teton County, Wyoming. Checked 2026-09-21.

Start by working out who issued the permit, because it may not be who you assume. DEQ is the permitting authority in Campbell for commercial systems only, plus Carbon, Niobrara, Platte and Weston opens in a new tab, and elsewhere the local authority may want different forms and additional information opens in a new tab. Ask the seller which office holds the file on the property.

In a delegated county the rules are local and often recent. Teton County's small wastewater regulations were adopted on 21 December 2021 and took effect on 1 January 2022 opens in a new tab, so an older system there was permitted under a different version of them. Ask which rules applied in the year yours went in.

One Wyoming quirk catches buyers around Cheyenne. All applications for water distribution systems or sewage collection systems within the Cheyenne Board of Public Utilities district must be submitted to the BOPU for approval opens in a new tab. If the property sits in that district, that is an extra desk in the chain rather than an alternative to the others.

Keeping a System Working

Sources: Teton County, Wyoming; U.S. Environmental Protection Agency. Checked 2026-09-21.

Wyoming's county rules are specific about the end of a tank's life: an abandoned tank must be pumped and the septage hauled to a licensed facility approved to receive the waste opens in a new tab. For the years before that, the EPA's guidance is an inspection at least every three years, with household tanks typically pumped every three to five opens in a new tab.

Help Paying for Repairs

Sources: Wyoming Department of Environmental Quality; U.S. Environmental Protection Agency. Checked 2026-09-21.

We found no Wyoming state programme that pays a household towards a septic repair, so this section is short and honest. The state's role here is the permit itself, and only in a handful of counties opens in a new tab. Ask your county, because a county that runs its own programme sometimes has its own arrangements too.

That leaves the federal programmes, and they are worth a call before any borrowing. The USDA runs grants and low-interest loans to repair, improve or modernize rural single-family homes opens in a new tab, and separately grants to elderly very-low-income homeowners to remove health and safety hazards, including septic systems opens in a new tab. The age and income tests decide which of the two you are asking about.

Find Your County's Septic Office

Wyoming delegates small wastewater permitting to counties that ask for it, so most counties issue their own permits and the state covers the rest. DEQ says it is the permitting authority in Campbell for commercial systems only, plus Carbon, Niobrara, Platte and Weston. The rows below name the office we could verify for each county; where a county runs its own programme, its rules are the ones that bind you even though the standards come from the state. Checked 2026-09-21.

CountyEnvironmental health office
CampbellWyoming Department of Environmental Quality, Water Quality Division opens in a new tabThis county has no delegated local authority for small wastewater systems, so the state is your permitting office. The general permit covers installation, repair or replacement of systems treating less than 2,000 gallons of domestic sewage per day, and DEQ publishes a list of approved septic tank models to choose from. Campbell is the partial case: DEQ is the permitting authority here for commercial systems only, so ask the county about a house system.
CarbonWyoming Department of Environmental Quality, Water Quality Division opens in a new tabThis county has no delegated local authority for small wastewater systems, so the state is your permitting office. The general permit covers installation, repair or replacement of systems treating less than 2,000 gallons of domestic sewage per day, and DEQ publishes a list of approved septic tank models to choose from.
NiobraraWyoming Department of Environmental Quality, Water Quality Division opens in a new tabThis county has no delegated local authority for small wastewater systems, so the state is your permitting office. The general permit covers installation, repair or replacement of systems treating less than 2,000 gallons of domestic sewage per day, and DEQ publishes a list of approved septic tank models to choose from.
PlatteWyoming Department of Environmental Quality, Water Quality Division opens in a new tabThis county has no delegated local authority for small wastewater systems, so the state is your permitting office. The general permit covers installation, repair or replacement of systems treating less than 2,000 gallons of domestic sewage per day, and DEQ publishes a list of approved septic tank models to choose from.
TetonTeton County Engineering Division opens in a new tabTeton County holds delegated authority from the Wyoming Department of Environmental Quality and runs its own Title 9 Small Wastewater Facility Regulations, adopted 21 December 2021 and effective 1 January 2022. Those rules are adapted from WYDEQ Water Quality Rules chapters 3 and 25, so the standards are the state's and the administration is the county's. The design engineer has to certify that the installation conforms to the approved design, before or alongside the county Sanitarian's final inspection.
WestonWyoming Department of Environmental Quality, Water Quality Division opens in a new tabThis county has no delegated local authority for small wastewater systems, so the state is your permitting office. The general permit covers installation, repair or replacement of systems treating less than 2,000 gallons of domestic sewage per day, and DEQ publishes a list of approved septic tank models to choose from.

Questions People Ask

Who issues a septic permit in Wyoming?

Usually your county. DEQ is the permitting authority in Campbell for commercial systems only, plus Carbon, Niobrara, Platte and Weston, and for other jurisdictions the local permitting authority may require different forms or additional information. Find the office before you fill in anything.

What does the state general permit cover?

Ordinary house systems and small commercial ones. It covers the installation, repair or replacement of individual or commercial sewage disposal systems treating less than 2,000 gallons of domestic sewage per day. Larger than that is a different permit.

Why does my county have its own septic rules?

Because Wyoming law lets it. Statute 35-11-304 provides that, to the extent requested, the authority to enforce and administer these permit provisions shall be delegated to qualifying municipalities, water and sewer districts or counties. Teton County's own regulations, for example, are an integral part of its delegation agreement with the state.

Do I need an engineer?

In a delegated county, expect to. In Teton County the design engineer has to certify that the installation conforms to the approved design, before or alongside the county Sanitarian's final inspection. The system also has to sit inside the general permit's 2,000 gallons per day limit to use that route.

Is there help paying for a replacement?

Nothing state-level that we could find. The realistic routes are federal: USDA grants and low-interest loans for repairing or modernizing rural single-family homes, and grants for elderly very-low-income homeowners to remove health and safety hazards including septic systems. Check which of the two your household fits.

Sources

Cities in Wyoming

Counties in Wyoming

How these are ranked

By verification score, out of 100, across six checks published in full on how we rank. No company paid to appear and none can pay to rank higher. The score counts records and is not a judgment about workmanship.