Living in Grenville, SD: what to set up and who to call
Tap water in Grenville comes from the Grenville 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 of 1.0 ppb. For a library card, the closest branch is Waubay Public Library, 10.4 miles out.
I’m new in town
What to set up in Grenville, 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 Grenville.
Power comes from NorthWestern Energy
NorthWestern Energy (NorthWestern Energy - (SD)), an investor-owned utility, serves all of Grenville. Its homes paid an average of 13.3¢ per kWh in 2025, about $125 a month (its average across South Dakota).
Start or move service: northwesternenergy.com · (800) 245-6977
Service territory: HIFLD Electric Retail Service Territories (map dated Aug 2023). Prices and customers: EIA-861, 2025.
Water comes from Grenville water system
The Grenville water system supplies almost all of Grenville. It buys treated surface water (EPA lists WEB Water as seller) and serves 48 people in all.
No health-based violations reported to EPA in the five years to October 2026, like 78% of the 11,392 systems serving <=100 people.
The latest lead result on file, the 90th percentile of homes sampled in Jan–Dec 2023, was 1.0 ppb, below the 15 ppb action level that applied. That’s higher than 55% of similar systems’ latest results.
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. Violations are counted by the start of their compliance period. SD4600146.
2 home internet providers serve Grenville
100% of 51 addresses can get 100/20 Mbps; 100% can get fiber.
| Provider | Technology | Addresses | Fastest (Mbps) |
|---|---|---|---|
| Venture Communications | Fiber | 100% | 1,000/1,000 |
| Verizon | Fixed wireless | 6% | 300/20 |
FCC National Broadband Map, as of December 2025. Availability as providers report it, not speeds people get.
We don’t have Grenville’s trash rules yet
Pickup rules, the dump and recycling in Grenville.
Where your child goes to school
Public school districts and the school path by grade.
Most of Grenville (93%) is in Webster School District 18-5; parts are in Langford School District 45-5 (7%).
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 Jul 2023; jurisdictions: EAC EAVS 2024. Registration rules and links: vote.gov, updated Aug 3, 2026.
Grenville spans 2 ZIP codes
ZIP codes where Grenville residents live, with the share of the town in each.
| ZIP | Post office name | Share of Grenville | ZIP’s residents in Grenville |
|---|---|---|---|
| 57239 | Grenville, SD | 96% | 18% |
| 57274 | Webster, SD | 4% | 0% |
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 Grenville
Who supplies Grenville’s drinking water, and has it had violations?
The Grenville water system (EPA ID SD4600146). 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 1.0 ppb (Jan–Dec 2023), against a 15 ppb action level.
Who provides electricity in Grenville?
NorthWestern Energy (NorthWestern Energy - (SD)), an investor-owned utility. Its homes paid about 13.3¢ per kWh in 2025 (EIA).
What internet providers serve Grenville?
Venture Communications, Verizon (FCC, as of December 2025).
What ZIP codes are in Grenville?
57239 (96%), 57274 (4%), by share of residents. Census 2020 ZIP Code Tabulation Areas.
What school district is Grenville in?
Webster School District 18-5. Parts of the city are in Langford School District 45-5.
How do I register to vote in Grenville?
South Dakota has no online registration; you can register in person until 15 days before Election Day or by mail (received 15 days before). Elections here are run by the Day County Auditor. Check your registration at vip.sdsos.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 Aug 3, 2026 (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.