Arizona ยท county water record
Water in Maricopa County
What the state and federal record says about water here, before you look at any particular piece of ground. Every finding names the agency it came from.
- 50,870 Wells on record across 9,283 square miles
- 570 ft Well depth middle value across 2,647 of 9,283 square miles
- 246 ft Depth to water middle value across 294 of 9,283 square miles
Point at any square mile to read what is on it. Hover the maps below to compare them.
Maricopa County by the square mile
Every finding on this page is one number for the whole county. These are the same records placed on the ground they came from.
Wells on record. Every well ADWR has a record of, exempt and non-exempt together.
- none on record (bare ground)
- up to 1
- 2
- 3 to 4
- 5 to 10
- 11 to 40
- over 40
9,283 surveyed sections, drawn 3 by 3 miles to a square. The shading is scaled against every county in Arizona, so a colour means the same thing on any of these pages. The outline is the county boundary from the Census Bureau: ground inside the line and outside the shading is ground nobody has drilled, filed on or addressed. Aerial imagery is the USGS National Map.
Stands out
Water rights here are still being decided in court
100% of the county falls inside a general stream adjudication that has run for decades and is not finished. Until it ends, who holds what is formally unsettled.
Arizona general stream adjudications 1 of 14 counties
100% here 1st of 14 One bar per Arizona county from lowest to highest. Point at one to name it.
Stands out
A lot of well registrations here have been cancelled
32% of well records are cancelled, against 20% across the state. A cancelled registration is not a well you can use.
ADWR wells registry 1 of 15 counties
32% here 1st of 15 One bar per Arizona county from lowest to highest. Point at one to name it.
Stands out
Water systems here are under enforcement
18% of the county is served by a system with a formal EPA or ADEQ enforcement action on record, against 3% across the state. An enforcement action is the step after a violation that was not fixed.
EPA Safe Drinking Water Information System 1 of 15 counties
18% here 1st of 15 One bar per Arizona county from lowest to highest. Point at one to name it.
Worth knowing
Wells here have to go a long way down
The typical well is 570 feet deep, against 332 ft across the state, across 50,870 wells on record. Drilling is priced by the foot and the casing with it, so depth is the first line of any estimate for putting water on raw land, and it is the number a seller is least likely to volunteer.
ADWR wells registry 2 of 15 counties
570 ft here 2nd of 15 One bar per Arizona county from lowest to highest. Point at one to name it.
Worth knowing
A lot of this county is in a mapped floodplain
39% of the county intersects a FEMA special flood hazard area, against 25% across the state. In Arizona that is usually a wash rather than a river, dry for most of the year and the reason the insurance is required anyway.
FEMA National Flood Hazard Layer 2 of 15 counties
39% here 2nd of 15 One bar per Arizona county from lowest to highest. Point at one to name it.
Worth knowing
Water sampled here comes back over a federal limit more often than it should
11.5% of groundwater samples in this county exceeded a federal drinking water standard, against 4% across the state, across 49,500 samples. In Arizona the usual culprit is arsenic, which is natural, invisible, and a treatment cost rather than a reason not to buy.
Water Quality Portal (USGS and EPA) 2 of 15 counties
11.5% here 2nd of 15 One bar per Arizona county from lowest to highest. Point at one to name it.
Worth knowing
Much of this county is inside an Active Management Area
53% of the county sits in Phoenix AMA. Inside an AMA the state limits new groundwater pumping and a subdivision must prove a hundred-year assured water supply before it can sell lots. Outside one, almost none of that applies, and which side of the line a property falls on changes what can be built there.
ADWR Active Management Areas 3 of 9 counties
53% here 3rd of 9 One bar per Arizona county from lowest to highest. Point at one to name it.
Worth knowing
A lot of this county is within five miles of a federal cleanup site
11% of the county lies within five miles of a Superfund site. Five miles is proximity rather than contamination, and it is the distance at which a groundwater plume stops being somebody else's problem.
EPA Superfund national priorities list 3 of 13 counties
11% here 3rd of 13 One bar per Arizona county from lowest to highest. Point at one to name it.
Worth knowing
The water here stands a long way below the surface
The water table sits 242 feet down in the typical square mile. That is not the depth of the hole, it is where the water stands in it, and it sets the pump, the lift and the power bill for as long as the well runs.
ADWR groundwater level change 4 of 15 counties
242 ft here 4th of 15 One bar per Arizona county from lowest to highest. Point at one to name it.
Worth knowing
Most of the parcels here have nothing built on them
38% of the county holds parcels with no situs address, meaning no building with a number on the door. This is raw land country, which is the market, and it also means few neighbours to share a road, a line or a well with.
County assessor parcel records 4 of 15 counties
38% here 4th of 15 One bar per Arizona county from lowest to highest. Point at one to name it.
Worth knowing
The land here is sinking where the aquifer was drawn down
2,021 mapped subsidence features and no confirmed fissures yet. Subsidence is what precedes a fissure, and it is worth knowing about before it becomes one.
AZGS earth fissure and subsidence mapping 1 of 9 counties
2,021 here 1st of 9 One bar per Arizona county from lowest to highest. Point at one to name it.
Worth knowing
Ground here has cracked open where the water was pumped out
507 confirmed earth fissures and 2,021 mapped subsidence features. Fissures open when an aquifer is drawn down and the land above settles unevenly. They swallow fences, roads and foundations, and no ordinary policy covers them.
507 here The bar is the whole county and the fill is this county's share.
Worth knowing
Buying here can come with a CAGRD bill attached
3.9% of the county is inside a CAGRD service area. Membership means an annual charge that replenishes the groundwater a property pumps, it runs with the land, and it rises.
3.9% here The bar is the whole county and the fill is this county's share.
Worth knowing
The irrigation water here is already spoken for
20,300 grandfathered irrigation rights are recorded in this county. Inside an AMA, ground that was already being irrigated in 1980 kept the right to go on doing it and no new irrigation right can be created. New ground does not get water by asking for it.
20,300 here The bar is the whole county and the fill is this county's share.
Worth knowing
This county is being platted into subdivisions
41,419 platted subdivisions are recorded here. Inside an AMA each one had to prove a hundred-year assured water supply before a lot could be sold; outside one, it did not, and the developer only had to disclose that fact.
41,419 here The bar is the whole county and the fill is this county's share.
This is the county. Your question is probably a property.
None of the above is about a particular parcel. Water is not parcel-shaped: the ditch serving the ground runs through other people's land and the senior right that curtails it sits somewhere else, which is why the state files by survey section rather than by property. Check an address and you get the square mile it sits in, with the wells, the rights and what was actually diverted.
Check a property in Maricopa County