Why this reaches associations rather than only developers

Montana subdivisions outside municipal service run on § 85-2-306 exempt wells — the 35 gallons-per-minute, 10-acre-feet exception. That is the authority behind a great many association water uses:

• irrigation of common area, entry landscaping and homeowners' parks
• a clubhouse, pool or bathhouse supply
• a replacement domestic well where the original has failed
• stock or fire-suppression water on a shared parcel

An association drilling for any of those now files a Notice of Intent before use and pays $400, plus $250 if it needs an extension. Budget the fee and DNRC's review time into the project rather than the drilling contract.

The constraint that bites hardest, and it is not the fee

It is the 10 acre-feet ceiling, which is a combined appropriation shared across a development's lots. In a subdivision where every lot has its own exempt domestic well, the association's new irrigation well is drawing on the same statutory allowance. That is the provision most likely to stop a phased build-out or an expansion of common-area landscaping — not the paperwork.

Two questions worth answering before the project, not during it:

• What is already appropriated under the exception in your development, across all lots and all association wells?
• For developments still handing over infrastructure: do the Notices of Intent exist, and have they been transferred? A declarant transition that moves the pipes and not the paperwork leaves the association operating a well whose authorisation sits with someone else.

Water and subdivisions: two recent court decisions worth knowing

Montana's appellate courts produced two 2026 rulings that bear directly on shared water and shared access in subdivisions.

In Dolan v. Ceartin, 2026 MT 73 (April 7, 2026), the Supreme Court affirmed that homeowners in the five-lot Cobb Hill Minor Subdivision near Four Corners held no implied easement in a feeder irrigation ditch crossing a neighbour's lot — because the subdivision's own DEQ certificate of subdivision approval required that the small feeder ditches across the lots “be abandoned.” The category-level lesson is that subdivision-approval conditions are part of the governing regime, alongside the declaration, and can defeat later easement claims among lot owners. The Water Court had separately found the plaintiffs had not abandoned their water right, noting that “water rights and ditch rights are separate and distinct rights.” The fee exposure is the other lesson: § 70-17-112(5), MCA imposes prevailing-party fee shifting on ditch-interference claims, and the stipulated award in that case was $145,000 before the appeal even began.³

In Vicevich v. Kultgen, 2026 MT 168 (July 28, 2026), the Court held a platted 60-foot private road easement in a five-lot minor subdivision was not extinguished by abandonment — non-use of an unimproved loop was insufficient, and abandonment of an express easement requires clear and convincing evidence. A later plat aggregation and a 2021 side agreement among some owners did not relocate or extinguish it. But the Court reversed the part of the judgment ordering removal of unidentified obstructions: an amended judgment must precisely identify the fence at issue and clarify that no other structure has been adjudicated. Fees there ran to $106,209 plus appellate fees.⁴

Read together: a platted road easement is durable and does not lapse from disuse, but injunctive relief has to name the specific encroachment — a catch-all “remove any obstructions” decree is not sustainable. And private-road and shared-irrigation disputes in small Montana subdivisions carry six-figure fee exposure on either side.

A sourcing caveat we are not going to bury

We read the proposed DNRC notice in full. We could not open the adoption notice — the department's document and news paths returned errors on repeated attempts. So the adoption facts specifically — Register Issue 18, September 26, 2025, the October 1, 2025 effective date, and “New Rules 1 through 7” — rest on the text of that DNRC page as indexed rather than a document we opened, and the final fee figures could in principle differ from the proposed ones. Treat the effective date and the fees as proposed-text-verified and adoption-unverified until the adoption notice is retrieved.

Separately, a requirement reported elsewhere that subdivision applicants must demonstrate an existing water right, a completed DNRC technical analysis, or an authorised Notice of Intent at the start of local review, with a January 1, 2026 trigger, is unverified. We did not find it in a document we opened.