Twenty-One Ranchhouse · Photo: Jon Roanhaus · CC BY-SA 4.0Living in Sweetwater, ID: what to set up and who to call
Sweetwater has no town government of its own, so Nez Perce County runs its elections and most services, and its children attend Lapwai School District 341. For a library card, the closest branch is Prairie-River District, 2.6 miles out.
I’m new in town
What to set up in Sweetwater, 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 Sweetwater.
Power comes from Avista
Avista (Avista Corp.), an investor-owned utility, serves all of Sweetwater. Its homes paid an average of 11.8¢ per kWh in 2025, about $107 a month (its average across Idaho).
Start or move service: avistacorp.com · (509) 489-0500
Service territory: HIFLD Electric Retail Service Territories (map dated Aug 2023). Prices and customers: EIA-861, 2025.
Water comes from South Lapwai water system
The South Lapwai water system supplies Sweetwater: about 33% of residents live in its service area. About 67% of homes are outside any mapped community water system, most likely on private wells, which EPA doesn’t regulate. It draws ground water and serves 235 people in all.
No health-based violations reported to EPA in the five years to October 2026, like 77% of the 15,074 systems serving 101–500 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. 101600003.
Which providers serve Sweetwater
This card will list the home internet providers the FCC’s National Broadband Map shows in Sweetwater, the share of addresses that can get 100/20 Mbps and the share with fiber, with the map’s “as of” date.
Source to come: FCC Broadband Data Collection.
We don’t have Sweetwater’s trash rules yet
Pickup rules, the dump and recycling in Sweetwater.
Where your child goes to school
Public school districts and the school path by grade.
Sweetwater is in Lapwai School District 341.
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.
No town hall: the county runs things
Sweetwater is unincorporated, so Nez Perce County is the local government.
Election office: FVAP local election office directory, updated Jun 2025; jurisdictions: EAC EAVS 2024. Registration rules and links: vote.gov, updated Sep 12, 2025.
Sweetwater is in ZIP code 83540
ZIP codes where Sweetwater residents live, with the share of the town in each.
| ZIP | Post office name | Share of Sweetwater | ZIP’s residents in Sweetwater |
|---|---|---|---|
| 83540 | Lapwai, ID | 100% | 7% |
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 Sweetwater
Who supplies Sweetwater’s drinking water, and has it had violations?
The South Lapwai water system (EPA ID 101600003). It reported no health-based violations to EPA in the five years to October 2026; 77% 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 Sweetwater?
Avista (Avista Corp.), an investor-owned utility. Its homes paid about 11.8¢ per kWh in 2025 (EIA).
What ZIP codes are in Sweetwater?
83540. Census 2020 ZIP Code Tabulation Areas.
What school district is Sweetwater in?
Lapwai School District 341.
How do I register to vote in Sweetwater?
In Idaho you can register online until 11 days before Election Day, in person up to and including Election Day, or by mail (received 11 days before). Elections here are run by the Nez Perce County Clerk. Check your registration at elections.sos.idaho.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 Sep 12, 2025 (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): pending.