Photo: J.B. Chandler · CC BY-SA 3.0Living in Big Sandy, MT: what to set up and who to call
Tap water in Big Sandy comes from the Town of Big Sandy water system, which has a clean five-year EPA record (about 22% of systems its size had a health-based violation) and a latest lead result below detection. Big Sandy Branch Library, at 60 Johannes East, is the library in town.
I’m new in town
What to set up in Big Sandy, and who provides it. Tap an answer for the details and where they come from.
Power, water and internet
Who to call to start service at a new address in Big Sandy.
Power comes from NorthWestern Energy
NorthWestern Energy (NorthWestern Energy LLC - (MT)), an investor-owned utility, serves all of Big Sandy. Its homes paid an average of 14.4¢ per kWh in 2025, about $102 a month (its average across Montana, for customers on its standard service). Montana lets you buy power from another supplier; 0% of NorthWestern Energy’s home customers do, and NorthWestern Energy still delivers it.
Start or move service: northwesternenergy.com · (888) 467-2669
Service territory: HIFLD Electric Retail Service Territories (map dated Aug 2023). Prices and customers: EIA-861, 2025.
Water comes from Town of Big Sandy water system
The Town of Big Sandy water system supplies almost all of Big Sandy. It draws ground water and serves 608 people in all.
No health-based violations reported to EPA in the five years to October 2026, like 78% of the 5,327 systems serving 501–1,000 people.
The latest lead result on file, the 90th percentile of homes sampled in Jan 2023–Dec 2025, was 0.0 ppb, below the 15 ppb action level that applied. Results below detection are reported as 0, so 0 doesn’t mean no lead at any tap.
The system’s full record: EPA ECHO report
EPA SDWIS via Envirofacts (violations pulled Oct 9, 2026) and ECHO (lead samples, 2026Q3); service area: EPA Community Water System Service Area Boundaries v3.0 (EPA’s estimate). Violations are counted by the start of their compliance period. MT0000150.
1 home internet providers serve Big Sandy
100% of 369 addresses can get 100/20 Mbps; 100% can get fiber.
| Provider | Technology | Addresses | Fastest (Mbps) |
|---|---|---|---|
| Triangle Communications | Fiber | 100% | 100/20 |
FCC National Broadband Map, as of December 2025. Availability as providers report it, not speeds people get.
We don’t have Big Sandy’s trash rules yet
Pickup rules, the dump and recycling in Big Sandy.
Where your child goes to school
Public school districts and the school path by grade.
Big Sandy is in Big Sandy K-12 Schools.
Test scores and every school: see Schools →U.S. Department of Education, NCES Common Core of Data, 2024–25. Enrollment rules and registration are the district’s.
Town hall and registering to vote
Who to call, and how to register.
Election office: FVAP local election office directory, updated Jan 2025; jurisdictions: EAC EAVS 2024. Registration rules and links: vote.gov, updated Nov 18, 2024.
Big Sandy is in ZIP code 59520
ZIP codes where Big Sandy residents live, with the share of the town in each.
| ZIP | Post office name | Share of Big Sandy | ZIP’s residents in Big Sandy |
|---|---|---|---|
| 59520 | Big Sandy, MT | 100% | 55% |
Census 2020 ZIP Code Tabulation Areas, by census block; post office names: GeoNames (CC BY 4.0). ZIPs created since 2020 are missing.
Getting around, the ER and the library
One line each; the subject pages have the rest.
ER: CMS hospital data. Library: IMLS Public Libraries Survey, FY2024.
Questions about living in Big Sandy
Who supplies Big Sandy’s drinking water, and has it had violations?
The Town of Big Sandy water system (EPA ID MT0000150). It reported no health-based violations to EPA in the five years to October 2026; 78% of systems its size had none. Its latest lead 90th percentile was 0.0 ppb (Jan 2023–Dec 2025), against a 15 ppb action level.
Who provides electricity in Big Sandy?
NorthWestern Energy (NorthWestern Energy LLC - (MT)), an investor-owned utility. Its homes paid about 14.4¢ per kWh in 2025 (EIA).
What internet providers serve Big Sandy?
Triangle Communications (FCC, as of December 2025).
What ZIP codes are in Big Sandy?
59520. Census 2020 ZIP Code Tabulation Areas.
What school district is Big Sandy in?
Big Sandy K-12 Schools.
How do I register to vote in Big Sandy?
Montana has no online registration; you can register in person up to and including Election Day or by mail (postmarked 30 days before). Elections here are run by the Chouteau County Election Administrator. Check your registration at prodvoterportal.mt.gov.
Sources & dates
Every answer above names its source. Here they are with their dates.
- Water: EPA SDWIS (Envirofacts, pulled Oct 9, 2026), ECHO SDWA 2026Q3, EPA CWS Service Area Boundaries v3.0.
- Power: HIFLD Electric Retail Service Territories (map Aug 2023); EIA-861 final 2025.
- Trash: OpenStreetMap, Geofabrik extract of Oct 9, 2026. © OpenStreetMap contributors (ODbL).
- ZIP codes: Census 2020 ZCTA relationship files; GeoNames postal codes (CC BY 4.0).
- Schools: NCES Common Core of Data, 2024–25.
- Registration: vote.gov, updated Nov 18, 2024 (read Oct 10, 2026). Official sites and area codes: Wikidata.
- Election office: FVAP local election office directory (fetched Oct 10, 2026; each record dated), EAC EAVS 2024 jurisdictions; registration and lookup links from vote.gov’s state data, checked Oct 10, 2026.
- Internet: FCC National Broadband Map, as of December 2025.