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Data sources

Where each number comes from, and what it cannot tell you.

Places to get water

Our own directory, compiled from public records and research

Standpipes, refill stations and water haulers. No Arizona agency publishes a statewide list of these, which is the gap this site exists to fill. Entries come from company records, utility announcements, news coverage and local knowledge, and each one shows where its details came from and when.

Limits: businesses close, phone numbers change and service areas shift. Distances are measured from a company's registered address, not from the edge of where it will actually drive, so a hauler further away may still deliver to you and a close one may not. Call before you count on any listing, as with any directory.

Water haulers

Federal Motor Carrier Safety Administration (FMCSA) census

Arizona licenses potable water hauling county by county (A.A.C. R18-4-125), and those permit lists are not published online. Haulers do drive trucks, though, and trucks are registered federally, so we search the FMCSA carrier census for Arizona carriers whose business names indicate water hauling: 74 companies across 36 cities.

Limits: matching on names is imperfect in both directions. A hauler named something like "Sunrise Transport" won't be found, and lookalikes have to be excluded by hand: "Winston Water Cooler" is a plumbing supplier, "Buckeye Water Conservation & Drainage District" is an irrigation district. Companies listed may haul only construction or dust-control water rather than potable.

Public water points

OpenStreetMap, ODbL

962 mapped drinking-water points across Arizona, contributed by volunteers. These fill the gap outside the communities the directory covers in detail, so that a search anywhere in the state returns something.

Limits: most are drinking fountains, park taps and campground spigots. They are useful for filling bottles or a jug and are not a way to fill a household storage tank. They are also unverified by us, and a volunteer-mapped tap may have been removed years ago.

Your water provider

ADWR Community Water System service areas

The official boundaries of Arizona's community water systems, used to answer who serves a given address: 846 mapped service areas. Each carries an ADEQ ID, which is the same identifier the EPA calls a PWSID, and that is what links your provider to its federal compliance record.

Limits: 113 systems in the source data have no mapped boundary at all, so they can never match an address and are excluded. A provider may also serve customers slightly outside its mapped area. If the site says no provider serves you but you receive a water bill, believe the bill. For much of rural Arizona, though, "no provider" is the true and important answer: no utility is obligated to bring water to that parcel.

Safety violations

EPA Safe Drinking Water Information System, via ECHO

Federal drinking-water compliance records for every active Arizona public water system, refreshed quarterly. Health-based violations are reported separately from total violations, violations that are still unresolved are counted on their own, and anything since 2021 is flagged as recent.

Limits: a violation is not automatically a health emergency. Many are monitoring or reporting failures, meaning a system did not test or file on time rather than that anything was found in the water. Records also run back decades, which is why raw totals are shown alongside recency rather than on their own. No violations on record does not guarantee your water is safe today. Private wells are not covered at all: they fall outside EPA and ADEQ drinking-water rules, so nobody tests them but you.

Wells

ADWR Wells55 registry, combined with the GWSI monitoring index

Wells55 is Arizona's well registration database: every well drilled in the state must be registered, including exempt domestic wells. That is roughly 218,000 records. GWSI, the Groundwater Site Inventory, is a much smaller network of about 46,800 sites where water levels are physically measured. The two are combined, treating points within 60 metres of each other as one well, for about 257,000 in total.

Limits: GWSI on its own is a monitoring sample, not a census, and undercounts real wells roughly ninefold, which is why it is not used alone. GWSI also includes springs and sites predating the 1980 registry, so not every point is a registered well. Depths and drill years are recorded inconsistently and are often blank. The Wells55 data reaches us through a public mirror published by the Arizona Association of Conservation Districts rather than directly from ADWR, so its refresh date is not something we can confirm.

Regulatory context

ADWR AMA/INA boundaries and Assured Water Supply determinations

Active Management Areas and Irrigation Non-Expansion Areas are the parts of Arizona with real groundwater regulation: all 11 are included. Assured and Adequate Water Supply determinations record where a subdivision had to prove a 100-year water supply before it could be approved: 5,594 of them.

Limits: this is background, not a verdict on your water. Being inside an AMA does not mean your supply is secure, and being outside one does not mean it is not. Rio Verde Foothills sits inside the Phoenix AMA and still lost its water access in 2023, because the problem there was the absence of a provider and of supply determinations on split lots, not the AMA boundary.

Turning an address into a location

U.S. Census Bureau geocoder, with Photon for suggestions

Addresses are matched by the Census Bureau's public geocoder, which knows US address ranges. Type-ahead suggestions come from Photon, which is built on OpenStreetMap. All of it runs in your browser: your address is never sent to us and nothing is stored.

Limits: the Census geocoder does not know every rural address, and rural addresses are much of the point of this site. When it cannot find one, the site falls back to the coordinates of the suggestion you picked and labels the result as approximate.