Where a Colorado report gets its records

Every record behind a Water Table report is public. That is not the moat and it was never going to be. Anyone can query the Division of Water Resources. What is genuinely hard is that the answer to "is the water on this listing real" is spread across agencies that do not share an identifier, publish on different schedules, and in several cases do not publish a statewide layer at all.

The counties that are not in the statewide layer

Colorado has no single authoritative parcel layer. There is a statewide composite, and it is thin or absent in exactly the counties where rural land actually trades. Costilla County, the county with the largest concentration of cheap subdivided rural parcels in the state, and the one where a buyer is most likely to be sold ground with no water, contributes tens of thousands of parcels that have to be pulled from the county assessor’s own service.

One of the source lines in the provenance table reads "Fremont County Assessor GIS, and Chaffee County published by the City of Salida". That is what this work looks like at the edges: a county whose parcels are served by a municipality inside it, found by looking, not by a directory. Nobody builds that from an API catalogue.

The joins neither agency publishes

The Division of Water Resources publishes structures and the rights filed against them. It separately publishes an irrigated-lands mapping: parcels, the crop on them, the irrigation method, and which structures supply each one. Nobody publishes the two joined, and the join is where the useful sentence lives.

That is the shape of most of the work here. Almost nothing in a report comes from a single query against a single agency: it comes from putting a structure beside a parcel, a well beside a scanned log, a court filing beside a survey section, and keeping every one of those joins honest about how confident it is.

Some of the record was never typed up

The state images the driller’s own completion report for wells and the scanned page often carries values the tabular record does not. Those images are catalogued and read page by page by a vision model, and the extracted values are set against the API’s, field by field, with the disagreements kept rather than resolved.

The same principle runs through the water court resumes, which are prose rather than data. Every filing carries its case number and a legal description of the ground, written the way a clerk wrote it in 1974 or last month. Turning that into "this filing is about this square mile" is a parsing problem with no specification, and it is tested against the corpus rather than against an assumption about the format.

What we refuse to do

• No averaging a sentinel. Agencies write -9999 and 0 to mean "not recorded". Those are nulled, never treated as measurements, and never clamped into range.
• No arbitrary pick. Where a record could supply several values, the report does not take the first one it finds and print it as the answer.
• No silent gap. A subject with nothing on record is printed as having nothing on record, in words, rather than being left out so the page looks fuller.
• No inference dressed as a record. Every finding is marked as one or the other, and the ones that are inferences say what they were inferred from.

Those four are not aspirations. Each of them is there because it was got wrong once, found, and fixed, and each has a test that fails if it comes back.

Everything is dated

Every source carries when it was last loaded and how far behind the publisher it is. Some of these move on a decade timescale, and irrigated-lands mapping is redone every few years, while others land weekly. A report that presents a decade-old irrigation map and a Tuesday well permit with the same confidence is lying by omission, so the report prints the age of what it read.

This is general information about Colorado law and records. It is not legal advice and not a title opinion. What applies to a particular piece of ground is settled by the documents filed against it.