Montana water data · Community in Hill County
Rocky Boy's Agency: well depth, groundwater and water rights
What the public record says about water in Rocky Boy's Agency: how deep wells go, where the water table sits, what wells produce, which water rights are on file, and which documented environmental sites are nearby. Area statistics orient you; a property report analyzes the records around one specific parcel.
Updated September 2026 · Based on 118 public records from MBMG GWIC, Montana DNRC, Montana DEQ, EPA SEMS, EPA UST Finder, US Census (place boundary)
Wells on record
111
12.9 per sq mi
Median well depth
79 ft
half of wells 48–115 ft
Median static water level
19 ft
70 measurements
Median tested yield
10 gpm
75 pump tests
Well depth
How deep are wells in Rocky Boy's Agency?
Of 93 wells with a recorded total depth, the median is 79 feet. Half were drilled between 48 and 115 feet; one in ten went deeper than 180 feet and one in ten found water shallower than 28 feet. Depth is set by local geology and position on the landscape, both of which change over short distances, so the spread matters as much as the median.
Static water level
19 ft
median depth to water at rest · half between 12 and 25 ft
The static level is how far below ground the water stands before pumping, measured by the driller at completion. It affects pump setting and operating cost, and it moves with season and with neighbouring use.
Well yield
10 gpm
median tested yield · half between 7 and 16 gpm
17% of tested wells produced under 5 gallons per minute and 24% produced 20 or more. These are short completion tests, not sustained-capacity tests; a household typically needs 3 to 5 gpm with storage.
Drilling activity
Recent well drilling in Rocky Boy's Agency
1 wells have been completed here since 2016. The newest log on file was completed April 14, 2024. Records run back to 1960.
What the wells are for
- Domestic78
- Unused10
- Monitoring7
- Irrigation1
- Public Water Supply1
How they were drilled
- Rotary26
- Cable18
- Forward Rotary17
- Unknown9
Drillers filing well logs in Rocky Boy's Agency
- Hickel & Tooke Drilling Co27 all-time · 2008
- Hi-line Drilling Inc23 all-time · 2002
- Parker Drilling13 all-time · 1977
- Billmayer Drilling12 all-time · 1961
- Briggs Drilling Co10 all-time · 1970
- Simpson Drilling Co.4 all-time · 1964
- Maxim Technologies4 all-time · 2001
- Chen-northern3 all-time · 1991
Ranked by well logs filed with GWIC, public record only. Not an endorsement, a referral or a paid listing; we have no business relationship with these companies. Verify licensing with the Montana Board of Water Well Contractors before hiring.
Water rights
Water rights on file in Rocky Boy's Agency
Montana DNRC lists 2 water rights with a point of diversion inside this area: 2 groundwater and 0 surface water, 2 of them active. The median priority date is 1992, and the oldest claim dates to 1980.
Types of right
- Ground Water Certificate2
Purposes
- Domestic1
- Irrigation1
DNRC basins
- 40H2
Area totals describe the neighbourhood, not any one parcel. Montana publishes no authoritative link between a parcel and a water right; whether a right attaches to a specific property is a property-level question that our reports answer with the DNRC abstract linked.
Environmental groundwater screening
Documented environmental sites in Rocky Boy's Agency
Petroleum releases
3
0 open · 3 resolved
Superfund program sites
1
none on the National Priorities List
Registered tank facilities
1
underground storage tanks, current and historical
A documented release or site in the area is not evidence that any particular well is affected. Whether a release reaches a well depends on groundwater flow direction, geology, well depth and construction, the extent of the plume and the cleanup performed. The most recent release reported here dates to 2001. A property report screens the sites within a quarter, half and one mile of a specific parcel and links the agency records.