How DitchBook is built

This page documents the pipeline behind the directory, the map, and the statistics — what the sources are, how records are joined and verified, what we refuse to publish, and where the gaps are. It exists because a good question deserves a public answer: the numbers below are computed from the same data, in the same build, as the pages they describe.

The pipeline

1. Seed. The census began from the Open Water Foundation's Colorado ditch and reservoir companies dataset — open data, gratefully credited.
2. Census. 1,123 of today's 1,387 companies are that original OWF seed, carried over row for row and not individually re-verified by DitchBook beyond the reconciliation below. DitchBook has added 264 more since — each one checked individually against a Secretary of State record before inclusion, never bulk-imported, with ambiguous candidates left out rather than guessed in. The full list, seed and additions alike, is reconciled monthly against the Colorado Secretary of State's business-entity data for current standing (see below). Current census: 1,387 companies.
3. Monthly SoS refresh. A monthly pull of the SoS dataset re-joins standing, principal office address, registered agent, and formation date by entity ID. Snapshots are kept, and the published "standings as of" date derives from the newest snapshot's own date (currently August 3, 2026) — never from the build clock, so a rebuild cannot dress stale standings up as fresh.
4. Water-rights matching. Companies are matched to their structures (WDIDs) in Colorado DWR's CDSS records. Only tier-1 matches are published — see the standard below. Currently 643 published matches (published August 20, 2026), each carrying its water source, earliest decreed right, and a citation link to the state record.
5. Full Administrative Structures census. DWR's full Administrative Structures dataset also contains records that do not appear in its current Net Amount water-right export. DitchBook reviews those separately rather than discarding them or treating them as decreed rights. Currently 6 independently verified administrative links appear on company pages in a separate panel. Each requires a DWR structure row plus primary evidence connecting the company to that physical asset or operational system. These links do not enter earliest-right dates, flow amounts, tier-1 match totals, or the map.
6. The map. Most pins use coordinates from Colorado DWR's structure records. 1 additional point uses an exact digitized coordinate from the cited DWR water-right record where the separate structures export omits that WDID. 4 named reservoir points currently use a labeled approximate interior location derived from an exact-name official USGS NHD waterbody polygon because DWR's coordinate is blank. These are never presented as surveyed dams, outlets, or legal diversion points, and DitchBook never substitutes a town centroid. 643 of the 643 matched companies are pinned; the remainder have no publishable structure coordinates. The optional Satellite toggle shows USDA/USGS National Map orthoimagery (public domain) through zoom 16, then hands off to Esri World Imagery (licensed; credited on the map to Esri, Vantor, Earthstar Geographics, and the GIS User Community) from zoom 17 to 19, where USGS has no sharper native pixels left to show.
7. County pages. Two separately-labeled county relationships are built from this same data, never blurred together: “operates structures in,” from the DWR water-structure county field above, and “registered in <city>,” from the Secretary of State's principal-address city, joined through a Colorado city-to-county crosswalk built from U.S. Census Bureau TIGERweb place-polygon geometry, corroborated by the USGS GNIS Domestic Names extract and the Colorado DOLA Municipal Boundary layer (full citation and manual corrections: see Sources below). A city that straddles a county line places its companies on every county it touches, never one guessed “primary.” Currently 905 companies carry a registered-address county placement; 482 don't (see Known gaps below).
8. Water-court résumé matching. Monthly, DitchBook runs each of Colorado's seven water courts' newly posted résumés through the same disciplined entity-name matching as the rest of the pipeline: the automated matcher found the company's name in the filing's raw text under strict rules: every word of the registered name, in order, with only spaces or commas between them — matching is case-insensitive, treats “&” and “and” as the same, treats punctuation inside the registered name (hyphens, apostrophes, periods) as word breaks, and ignores a leading “The” — never a fuzzy match. When the registered name ends in a legal-form word, that word is required too (“Park Ditch Company” requires the word “Company”; a bare “Park Ditch” mention can never trigger it) — with one abbreviation family: where the name ends in “Association” or “Assn”, the filing may use any of “Association”, “Assn”, or “Assoc”. Beyond that, the matcher's remaining guards only ever remove listings, never add them. DitchBook publishes which companies were named: a “Water court activity” section on the company's own page, and the resume watch page itself. Currently 16 companies carry a mention across 3 month(s) of coverage.
9. Public-notice matching. Newspaper notices and company advertisements are captured with their publication date, newspaper page or indexed record locator, URL, retrieval date, and SHA-256 capture hash. Full registered names or separately sourced one-entity aliases may enter review; fuzzy, short-name, ambiguous, and privacy-sensitive hits do not publish. A human decision is required for every event. The current Notice Watch contains 81 approved event(s) across 71 company page(s), from 2 source registry with actual captures. Registered sources with zero captures are reported as not yet crawled, not counted as coverage.
10. One-pass publication. Every company page, basin index, the map data, the stats, and this page are generated from the same joined dataset in a single build. A number quoted anywhere on the site cannot disagree with the page it links to, because they are the same data. Builds hard-fail if a data source comes up short (a sparse map or a standings join covering less than half the census refuses to ship).

What "tier 1" means

A company-to-WDID match is published only when the state's own records assert it. The match key is the DWR structure record's associated-contacts field — the state's note of which organization is tied to the structure — which must equal the company's registered name exactly after mechanical normalization (case, punctuation, generic legal words; no fuzzy matching in anything published). Three guards then apply: the normalized name must map to exactly one registered company in the census (name collisions demote both candidates), all of a match's structures must sit in a single county (multi-county spread is the signature of a generic name conflating unrelated entities), and only ditch/reservoir-type structures are eligible (a company appearing as a secondary contact on a well must not be credited with the well's rights — a guard added after our own audit caught precisely that failure). The single-county guard belongs to the automated tier. A match promoted by individual verification is not subject to it, because a real irrigation company can and does cross a county line: 25 of the 643 published matches span adjacent counties — Larimer and Weld, Delta and Gunnison, Bent and Kiowa and Prowers among them — and each of those was individually verified against the state record before it was published. A fuzzy name-similarity tier exists in the pipeline for review purposes and is never published. Every published row carries a citation URL to the underlying state record. When post-publication review finds a conflict, the match is demoted and unpublished: on July 21, 2026 an internal audit demoted three previously published matches over basin conflicts. We treat the demotions as part of the record — a verifier with no public refusals is a rubber stamp.

See the full picture: how companies are matched to their ditches →

The numbers right now

Companies in the census

1,387

Matched to a current SoS record

1,376 (99%) — standings as of August 3, 2026

Published tier-1 water matches

643 — published August 20, 2026

Company pages with sourced contact details

327

Approved public-notice events

81 across 71 company page(s)

Companies pinned on the map

643

Company profiles

Some company pages carry a fuller profile: the water rights decreed to the company's structures, how much land the state has mapped as irrigated by them, what the diversion records show, and where that land sits. These panels appear only where the underlying public data exists and has been assembled for that company — a page without them is not a company without a history, only one whose records we haven't compiled yet. Every panel carries its own source and date, and every figure is shown as the state records it.

• Company contact census — phone, email, and mailing details are published only when they appear in an official public directory or filing, on the company's own site, in a public notice placed under the company's name, on its administrator's company-specific page, or in multiple corroborating public records. Every card states which evidence lane it uses, the source's update year, the date DitchBook checked it, and the exact source listing name. A public contact does not mean the company claimed or approved its page. Older records are labeled as older rather than made to look current, and every card links to a correction/removal path.
• Public-notice activity — dated newspaper notices and company advertisements are published only after exact-entity matching and human review. The company page shows the reviewer-written event summary, source page or record locator, and an explicit historical limitation; the raw transcription and private shareholder, estate, or lienholder names do not enter the public site. A notice proves what was published on that date, not today's contact, owner, value, meeting schedule, or operating status. Current source-by-source coverage is reported on the Notice Watch coverage table.
• Water-right portfolio — DWR's Water Rights Net Amounts, by structure (WDID): priority, appropriation and adjudication dates, decreed amount, whether the right is absolute or conditional, and the decreed uses. Each panel is stamped with the date the rows were pulled. Amounts are never converted, combined, or divided. DWR also records some net amounts only as alternate-point or exchange (APEX) entries; those are not listed in the table, so the panel says how many exist rather than letting the table imply it is the whole file.
• Irrigated acreage history — the Colorado Decision Support System's Irrigated Lands snapshots, which map irrigated parcels in particular years rather than every year. The parcels are mapped by the state. Where a parcel is served by more than one structure, or is also linked to a well, the acres are not all attributable to one company's ditch, and the panel says so in plain language.
• Recorded diversions — DWR's annual diversion records, labeled as the state labels them: published records are final; provisional records are not, and are drawn and marked differently so an unfinalized number never looks settled. Annual totals follow the DWR water year, November through October, not the calendar year — and the water year still in progress is marked partial, because a year that is only part-recorded would otherwise read as a collapse in supply. Diversions are never summed across a company's structures: structures on one system can feed each other, so the same water may appear on two records, and because each structure's record begins and ends in a different year a combined series would show a drop that is an artifact of the recordkeeping rather than anything that happened to the water. The chart shows one structure; the table shows them all. A diversion record shows what ran through a headgate. It is not a share, an entitlement, or a company allocation.
• Share counts — published only when a document states one, cited to that document with its date, and quoted where the wording matters. A count is what that record said on that date, not a certification of the company's present share structure, and the page says so on its face. Where we have not verified a count, the page says so rather than estimating. DitchBook does not calculate water per share, and no page divides a decreed amount by a share count. Where a court has found a per-share figure, that finding is quoted with its case number, the shares it examined, and the study period it covered — a court's finding speaks to the case in front of it, not to the whole company.
• Irrigated land linked to this company — the state-mapped irrigated-parcel footprint for the company's structures, drawn on a map. A service-area outline is sometimes shown behind it, dashed and labeled as context only; it is never used for any figure on the page.
• Ditch/canal alignment — a verified alignment between the company's own DWR structure and a named feature in the USGS National Hydrography Dataset (NHD), drawn on the map above (where a footprint exists) or, for a company with no footprint on file, on its own lines-only map instead. Every structure DitchBook reviews for a possible alignment is individually checked — never published on a name-comparison score alone — and recorded, whether or not a line results, in a never-delete decision ledger, so a “no line” is a checked and logged outcome, not silence. The coverage figures shown (“shown for N of M reviewed structures”) count only that reviewed roster, never a company's full structure list. Currently 160 of 215 reviewed ditch structures across 155 companies carry a published alignment; this expands in batches, each individually reviewed before publication. Reservoir structures — a dam or pool, as opposed to a ditch's own intake or headgate — are matched separately, against the water body the structure impounds rather than a named canal feature: currently 139 of 197 reviewed reservoir structures across 74 companies carry a published pool, reviewed under the same individual-check discipline as the alignments above.
• 6 of 26 Boulder County lines use county-verified alignment (Boulder County Parks and Open Space, CC0-1.0) instead of USGS NHD — see water/evidence/2026-08-09-boulder-alignment/ for the comparison.
• “Follow the water” — on 144 structures across 141 companies, drawn from 62 traced rivers, a “Follow the water” button on the structure's map popup, its company page, and an address-search result draws that structure's own headgate back along its water source to the river's headwaters, continuing onto the company's own reviewed canal alignment where one is published. River journeys follow the mapped watercourse, which may pass through reservoir pools en route; the journey names the watercourse, not every water body it crosses. It traces mapped hydrography, not a water right or a delivery guarantee — the same caveat accompanies every journey on the page itself.
• Rivers — a separate, optional map layer (default off; a “Rivers” toggle on the statewide map) draws 62 source rivers traced back from a verified headgate to their own headwaters. It shows only the rivers that feed a verified company's structure — not every Colorado waterway — and clicking one lists the companies DWR records show diverting from it.
• Basins — a separate, optional map layer (default off; a “Basins” toggle on the statewide map) paints the 9 CWCB/IBCC Basin Roundtable boundaries (the 2005 statutory roundtables, C.R.S. 37-75-104(3)(b); CDSS shapefile edition 11/9/2020) as translucent, colored fills in the same 9 basin colors the map's own pins already use. The shapes are simplified for display, not survey-grade, and clicking one filters the map to that basin — the same filter a pin's own basin color already offers. These polygons are for orientation and click-filtering only: a company's recorded basin is never determined, overridden, or corroborated by them, at build time or runtime. A small number of companies (38 of 643 published map pins with a recorded basin today) are recorded under a different basin than the one this map's boundary shows for their pin. These are individually reviewed as corrections come in — see the “Basin assignment” gap below.
• Map accuracy — the published ditch/canal alignments and reservoir pool outlines above come from the USGS National Hydrography Dataset, compiled at 1:24,000 scale; the optional satellite imagery layer (past zoom 17) carries its own, separate positional variability. When a drawn line or pool and the satellite image appear to disagree at close zoom, that is not evidence the published geometry is wrong — imagery georegistration is not more authoritative than the surveyed record it's being compared against, and the map itself says so at that zoom.
• Evapotranspiration — satellite evapotranspiration estimates are not shown on company pages. The renderer exists and stays switched off. An ensemble estimate covers all water reaching a field, including precipitation, wells, and shallow groundwater, so it is not a company's water use and could be badly misread as one. If it is ever published, it will carry that limit on its face.

These panels are a compilation of the public record, offered so a volunteer secretary can see the company's water history in one place without a records request. They are informational, accuracy is not guaranteed, and they are not a determination of historical consumptive use — quantification for water court requires a licensed engineering analysis. The corrections address applies here as it does everywhere else on the site.

Why a mapped ditch may not be visible on the ground

Ditch and canal alignments on our maps come from the USGS National Hydrography Dataset, matched to DWR structures as described above. The mapped course records where the channel runs — not whether water is visible there. Many Colorado ditches, especially through towns and newer development, flow in underground pipe or culvert for part of their course, carry water only during irrigation season, or sit beneath tree cover. A line on our map asserts the record's alignment; it does not assert open water at any particular spot or on any particular day.

Known gaps, stated plainly

• 11 census companies have no row in the current SoS pull — typically a name or registration mismatch still being reconciled, not a judgment about the company.
• Roughly 1,100 further SoS entities are candidates for the census and await individual verification before inclusion; the census understates the true population until that triage completes.
• The SoS status "Exists" is displayed as the state records it — it is not the same as "Good Standing," and we don't conflate them.
• Water matching is deliberately conservative: many true company-to-structure relationships remain unpublished because they haven't yet cleared the tier-1 bar. The backlog is verification time, not missing data.
• A DWR Administrative Structures record can exist without a current Net Amount water-right row. When independent evidence verifies the company relationship, DitchBook may show it in a separately labeled administrative panel; that panel does not establish a current decree, flow amount, or ownership of every component in an operating system.
• Basin assignment prefers the census's IBCC basin field; where blank, it derives from the DWR water division of the matched structure, and companies with neither appear under "Other."
• The "registered in <city>" county relationship isn't available for every company: of 1,387 census companies, 11 don't join to the current Secretary of State pull at all, 461 have no principal address on file, and 10 list an out-of-state address — none of these are guessed at, they're simply not shown by county.

Corrections

If anything on this site is wrong, tell us — corrections ship same-day, and material ones are noted rather than silently overwritten. Missing companies are added the same day they're verified.

On August 5, 2026, three Title 37 irrigation districts — Riverside Irrigation District, Orchard Mesa Irrigation District, and Palisade Irrigation District — were removed from the census. An irrigation district is a statutory taxing/assessment authority, not a shareholder-owned mutual ditch company, and doesn't meet the census's own admission rules; their presence in the original OWF-derived seed was an oversight this correction fixes. One of the three, Palisade Irrigation District, had carried a published water-rights match (WDID 7200817); that match is withdrawn with this correction.

Maintainer, disclaimer, and citing this work

This registry is maintained by Nick Davis (DitchBook, Loveland, Colorado — nick@getditchbook.com). It is a compilation of public records offered in good faith, with citations so any claim can be checked at its source; DitchBook is not affiliated with any listed company, the State of Colorado, or DARCA, and nothing here is a warranty — verify against the cited state record before relying on a row for any consequential purpose. Suggested citation: “DitchBook, Colorado ditch company registry, getditchbook.com/methods/, records as of August 3, 2026.”