What a well registration does not tell you

Arizona keeps a registry of wells, and it is one of the better public records in the country: hundreds of thousands of rows carrying location, depth, casing, pump capacity, intended use and the driller’s log. It is also read wrongly more often than any other source we handle, because several of its columns look like measurements and are not.

A fifth of the registry is canceled or superseded, and another large block is monitoring and observation holes, drilled to watch an aquifer rather than to take water from it. Counting rows and calling the result "wells nearby" overstates the neighborhood by a wide margin, and it is the first thing a naive read gets wrong.

The exempt well

A well pumping no more than thirty-five gallons a minute for non-irrigation use sits in a lighter category, which is how a single household on rural land gets water without a withdrawal permit.

A well with a pump capacity of not more than thirty-five gallons per minute, withdrawing groundwater for non-irrigation use, is an exempt well and is not subject to the withdrawal permit requirements that apply to other wells.

A.R.S. 45-454

The category is defined by pump capacity and by use, not by how much is actually taken, and it is narrower than the phrase "exempt well" suggests. It does not authorize irrigating a field, and inside a management area the surrounding rules still apply to the land even where they do not apply to the pump.

Zero is not a measurement

Tens of thousands of registrations carry no drilled depth at all, and in several of the published extracts an absent value arrives as a zero rather than as a blank. Averaging those in produces a figure that is wrong by hundreds of feet and looks entirely reasonable on a page. Every one of them is nulled here, never clamped and never counted, and the report says how many wells the distribution is actually built from.

The same applies to the use column, which arrives as several uses concatenated into one string. Split it wrongly and a stock well becomes a domestic one.

Read carefully, with canceled registrations removed, monitoring holes removed and absent depths excluded rather than zeroed, the neighboring registrations answer the question the listing never does: how deep drillers have had to go around here, and what they found when they got there.

Which questions answer this

• Land report, "Can I get a household well, and what will it cost all in?": whether a household well needs only a notice here, and the depth, yield and cost of wells within a mile.
• Land report, "Is the groundwater holding up?": water levels measured within a mile, and how many wells nearby were deepened.
• Rights report, "Am I in compliance?": whether a well is registered, and the metering that applies to it.

This is general information about Arizona law and records. It is not legal advice or a title search. What applies to a particular parcel is settled by the documents filed against it.