What to Check on Water and Septic Before Buying Acreage Near Billings

Last reviewed October 5, 2026. Rules are linked to the agencies that publish them.

What should you check on water and septic before buying acreage near Billings?

Before buying acreage near Billings, check four things: whether the well produces enough water, whether a legal water right or groundwater filing backs it, whether the septic system was permitted for the home's bedroom count, and what condition the septic system is in today. A well on the land and a septic tank in the yard do not answer any of those questions on their own.

I have seen every one of these go wrong on rural properties around Billings: septic systems that had failed, systems that were permitted for fewer bedrooms than the house has, systems that were never permitted at all, and wells that could not produce enough water without adding a cistern as a holding tank. Each one is expensive to fix after closing and much cheaper to find during inspection.

Key takeaways

• Have the septic system pumped, the lines inspected with a camera and the system flow tested before you remove your inspection contingency.
• In Yellowstone County, septic permits come from RiverStone Health, and permits are sized by bedroom count. Compare the permit to the actual number of bedrooms.
• A well log is a construction record, not a water right. Pull both from the Montana DNRC.
• Since January 1, 2026, Montana requires a Notice of Intent (Form 602I) before using groundwater under the exempt-well exception, plus a Notice of Completion (Form 602) within 60 days after use begins.
• A well that tests low on flow may still work with a cistern, but budget for it before you make an offer final.

How do you inspect a septic system on rural property near Billings?

A full septic inspection has three parts, and I recommend all three on every rural purchase because a septic system is typically one of the most expensive components on the property to repair or replace:

• Pump the tank. Pumping lets the inspector see the tank's condition, baffles and liquid levels instead of guessing from the surface.
• Camera the lines. A camera run shows cracks, root intrusion, collapses or separations between the house and the drainfield.
• Flow test the system. Running a measured volume of water through the system shows whether the drainfield can still accept and absorb wastewater.

Then compare what you found to the paperwork. In Yellowstone County, RiverStone Health's Environmental Health Services issues septic permits and inspects new and repaired systems. Permits are tied to bedroom count, and RiverStone Health counts an unfinished basement as one bedroom. Ask for the permit, the approved design and any repair records, and check them against the house as it stands today.

What septic problems show up most often?

• Failed systems. A drainfield that no longer absorbs wastewater usually means replacement, not repair.
• Undersized permits. A home that has added bedrooms since the system was permitted may be over its approved capacity. That can matter for financing, for resale and for any future permit you need.
• No permit at all. Some older or owner-installed systems were never permitted. Find out before closing what it would take to bring the system into compliance.

How far must a septic system be from the well?

Under Montana DEQ's minimum setbacks for subdivision review in ARM 17.36.323, a drainfield must be at least 100 feet from a private drinking water well, a septic tank at least 50 feet from one, and a drainfield at least 100 feet from the 100-year floodplain unless a waiver applies. County rules for individual permits can add requirements, so confirm the numbers with RiverStone Health for a specific parcel. Ask for a site map that shows the well, tank, drainfield, replacement drainfield area and property lines together.

How do you check the well and the water right?

Check the well's production and the legal record separately, because one does not prove the other.

Production and water quality

Ask for a flow or production test, the well depth, the static water level and the pump and pressure tank details. A well that produces too little water at peak demand is a common rural problem. Sometimes the fix is a cistern that stores water between pump cycles, which adds cost and maintenance but can make a low-producing well usable. Find out during inspection, not after you move in.

Test the water itself. At minimum, test for bacteria and nitrate, and consider a broader panel if the land has a history of livestock, fuel storage or farming nearby.

The legal record

A well log is a construction record. It shows when and how the well was drilled, but it does not create a water right. The Montana Department of Natural Resources and Conservation (DNRC) keeps water-right records separately, so pull both and confirm the water right covers the uses you plan, such as a second home, livestock or irrigation.

What changed for exempt wells in 2026?

Most household wells on rural acreage fall under Montana's exempt-well exception: 35 gallons per minute or less, not to exceed 10 acre-feet per year. Starting January 1, 2026, anyone using that exception must file a Notice of Intent to Appropriate Groundwater (Form 602I) with DNRC before putting the water to use, then a Notice of Completion of Groundwater Development (Form 602) within 60 days after use begins, according to DNRC's permit exceptions page. If the well on a property you are buying was drilled recently, confirm those filings were made.

What if the property has a cistern or city water?

Cistern. Confirm the tank's capacity, material and age, where it sits, how it is refilled, whether delivery trucks can reach it in winter, and how it is protected from freezing. Compare the tank size with how much water your household actually uses.

City or district water. A Billings mailing address does not mean the City of Billings provides water. Get written confirmation from the provider that the parcel is connected, along with meter status and any connection fees. My guide to utilities in Billings compares city water and private wells across the area.

Does lot size guarantee you can add a shop, guest house or second home?

No. Whether a parcel can support more septic capacity depends on soil conditions, setbacks, floodplain location and whether there is room for a replacement drainfield, not on acreage alone. The water right also has to cover the added use. If you plan to build a shop with a bathroom, a guest house or another dwelling, confirm both the septic and water questions during your contingency period.

Which county is the property in?

Confirm the county of record and legal description before relying on any rule. Properties with a Billings or Laurel mailing address can sit in Yellowstone, Carbon or Stillwater County, and each county has its own sanitation authority and records. RiverStone Health handles septic permits in Yellowstone County only.

Frequently asked questions

Should I get a septic inspection when buying a rural home near Billings?

Yes. Have the tank pumped, the lines inspected with a camera and the system flow tested, then compare the results to the county permit. Septic systems are typically among the most expensive parts of a rural property to repair or replace.

Who issues septic permits in Yellowstone County?

RiverStone Health's Environmental Health Services issues septic permits in Yellowstone County and inspects new and repaired systems before they are put into use. Permits are based on bedroom count, and an unfinished basement counts as one bedroom.

Is a well log the same as a water right in Montana?

No. A well log documents how a well was built. The water right is a separate record kept by the Montana DNRC, and buyers should pull both and confirm the right covers their planned uses.

What changed for Montana exempt wells on January 1, 2026?

Anyone using the exempt-well exception, 35 gallons per minute or less and no more than 10 acre-feet per year, must now file a Notice of Intent to Appropriate Groundwater (Form 602I) with DNRC before using the water, and a Notice of Completion (Form 602) within 60 days after use begins.

What if a well does not produce enough water?

A low-producing well can sometimes be made workable with a cistern that stores water as a holding tank, but that adds cost. A flow test during inspection tells you whether you need one before you commit to the purchase.

Is property near Billings in the Yellowstone Controlled Groundwater Area?

No. The Yellowstone Controlled Groundwater Area covers communities next to Yellowstone National Park, such as West Yellowstone, Gardiner and Cooke City-Silver Gate, under a water compact with the National Park Service, according to DNRC. It does not include Billings or Yellowstone County.

If you are relocating to Billings and looking at acreage, my guide to moving to Billings covers the rest of the move, and the Moving to Billings resource page has my relocation resources. To talk through a specific property, call or text me at 406-861-4844.

Gene Hauck is a Real Estate Broker and REALTOR® with The Morales Group at Engel & Völkers Billings, 1921 1st Ave N, Billings, MT 59101. He works with buyers relocating to Billings, real estate investors and Billings-area homeowners selling their homes. Call or text 406-861-4844.

This article is general information, not legal or engineering advice. Confirm water rights, septic permits and setbacks with the Montana DNRC, the county sanitation authority and qualified inspectors. Equal Housing Opportunity.