Photo: Tamanoeconomico · CC BY-SA 4.0Living in Caldwell, ID: what to set up and who to call
Caldwell spans 4 ZIP codes; 83605 holds the most residents (62%). The closest ER is West Valley Medical Center, 1.9 miles away.
I’m new in town
What to set up in Caldwell, 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 Caldwell.
Power comes from Idaho Power
Idaho Power (Idaho Power Co), an investor-owned utility, serves all of Caldwell. Its homes paid an average of 11.8¢ per kWh in 2025, about $106 a month (its average across Idaho).
Start or move service: idahopower.com · (800) 488-6151
Service territory: HIFLD Electric Retail Service Territories (map dated Aug 2023). Prices and customers: EIA-861, 2025.
Water comes from City of Caldwell water system
The City of Caldwell water system supplies Caldwell: about 91% of residents live in its service area. About 8% 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 74,000 people in all.
No health-based violations reported to EPA in the five years to October 2026, like 90% of the 597 systems serving 50,001–100,000 people.
The latest lead result on file, the 90th percentile of homes sampled in Jan 2024–Dec 2026, 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. ID3140013.
8 home internet providers serve Caldwell
100% of 21,067 addresses can get 100/20 Mbps; 51% can get fiber.
| Provider | Technology | Addresses | Fastest (Mbps) |
|---|---|---|---|
| Sparklight | Cable, Fiber | 100% | 1,000/50 |
| CenturyLink | DSL, Fiber | 58% | 140/20 |
| TDS Telecom | Fiber | 41% | 8,000/8,000 |
| Quantum Fiber | Fiber | 26% | 2,000/1,000 |
| Rise Broadband | Fixed wireless | 89% | 300/60 |
| Anthem Broadband | Fixed wireless | 86% | 1,000/1,000 |
FCC National Broadband Map, as of December 2025. Availability as providers report it, not speeds people get.
We don’t have Caldwell’s trash rules yet
Pickup rules, the dump and recycling in Caldwell.
Where your child goes to school
Public school districts and the school path by grade.
Most of Caldwell (50%) is in Vallivue School District 139; parts are in Caldwell School District 132 (50%).
CSchool gradeSee 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 Nov 2025; jurisdictions: EAC EAVS 2024. Registration rules and links: vote.gov, updated Sep 12, 2025.
Caldwell spans 4 ZIP codes
ZIP codes where Caldwell residents live, with the share of the town in each.
| ZIP | Post office name | Share of Caldwell | ZIP’s residents in Caldwell |
|---|---|---|---|
| 83605 | Caldwell, ID | 62% | 96% |
| 83607 | Caldwell, ID | 30% | 50% |
| 83687 | Nampa, ID | 7% | 11% |
| 83651 | Nampa, ID | 1% | 2% |
83606 is P.O. box or single-organization ZIP with no homes.
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 Caldwell
Who supplies Caldwell’s drinking water, and has it had violations?
The City of Caldwell water system (EPA ID ID3140013). It reported no health-based violations to EPA in the five years to October 2026; 90% of systems its size had none. Its latest lead 90th percentile was 0.0 ppb (Jan 2024–Dec 2026), against a 15 ppb action level.
Who provides electricity in Caldwell?
Idaho Power (Idaho Power Co), an investor-owned utility. Its homes paid about 11.8¢ per kWh in 2025 (EIA).
What internet providers serve Caldwell?
Sparklight, CenturyLink, TDS Telecom, Quantum Fiber, Rise Broadband, Anthem Broadband (FCC, as of December 2025).
What ZIP codes are in Caldwell?
83605 (62%), 83607 (30%), 83687 (7%), 83651 (1%), by share of residents. Census 2020 ZIP Code Tabulation Areas.
What school district is Caldwell in?
Vallivue School District 139. Parts of the city are in Caldwell School District 132.
How do I register to vote in Caldwell?
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 Canyon 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 National Broadband Map, as of December 2025.