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COORS B4

Structure dossier · WDID 0703407 · RESERVOIR · CLEAR CREEK · DWR record

Coors B4 is a reservoir on Clear Creek in Colorado. This page is its public record: the water it has a right to, whether it may take it today, and its history, compiled from the Colorado Division of Water Resources.

Source DWR administrative record · verify at DWR structure ↗ Source DWR administrative record · verify at DWR diversion records ↗ Source Our computation, scored against a reference · scored against DWR's call analysis, see /methods

Where this page's figures come from

Generated 2026-10-14 16:57 by Hydrohistorian. Sources: DWR HydroBase snapshot HydroBase_CO_20260928 (history) + CDSS REST (current), USGS NWIS cross-checks. Engine v0.5.0 (c7f5ca1) — every figure regenerates from this named code version and data image.

The record and the river

Download this structure

Everything on this page as data you can work with — and a README that makes it citable: the HydroBase snapshot it was built from, the build commit, what every column means, the method behind each derived figure, and that method's stated limits.

⇩ Full record (.zip) Print / save as PDF

Or one table at a time: rights.csv · annual_use.csv · curtailment_now.csv · court_cases.csv · co_parties.csv · call_climatology.csv

What is in the bundle
  • rights.csv — every decreed right, most senior first, with admin numbers, dates, amounts, uses and case numbers.
  • annual_use.csv — recorded diversion by year, with releases accounted separately.
  • curtailment_now.csv — each right's current priority status and how often it was out across analog years.
  • court_cases.csv — the cases attached to its rights.
  • co_parties.csv — the other structures that were parties to those cases. Not available anywhere else.
  • call_climatology.csv — how often each right has been out of priority by week of season, with confidence intervals and the seasons the record could actually judge.
  • README.txt — provenance, methods, limits, disclaimer, and links back to DWR's own records for verification.

Where it sits

Location as DWR records it (storage). Faint dots are the neighbouring water; click any to open it.

Current administration

● Fully called out — call at WANNAMAKER DITCH (CLEAR CREEK, priority 1870-05-23).

Which of its rights are out of priority?

Under today's controlling call (WANNAMAKER DITCH, priority 1870-05-23): 4 of this structure's 4 rights are out of priority now. (7 call(s) state no district and sit outside this one — not judged, not assumed.) In the 5 past years most like this one (2023, 2022, 2024, 2018, 2019), 4 of the rights shown below were out at least one week in at least one analog year.

Right (priority)NowAnalog years outMajority out by
1902-03-04 19055 ● out 5 of 5 2026-10-01
1965-10-31 43829 ● out 5 of 5 2026-10-01
1968-03-22 43829 ● out 5 of 5 2026-10-01
2017-11-22 61322 ● out 5 of 5 2026-10-01
How this table is built, and what it is not

“Now” compares each right's admin number with today's most senior applicable active call. The outlook uses flows at COORS B4 LAKE FROM ROCKY MOUNTAIN DITCH around 2026-10-01 (the newest reading on file) — currently 269% of that gage's own median for this window — to pick the 5 most similar past years with complete administration records (2004–2026). Only calls that verifiably apply count: DWR's own district statements in the call's set comments, a caller located in this district, or — on the same stream, where DWR records both stream miles (measured from the mouth) — a caller DOWNSTREAM of this structure. An upstream senior cannot demand water this diversion never deprives it of. Calls that state nothing and sit elsewhere are counted as unjudged rather than assumed, which also means the verified record is shorter than the raw one: early calls rarely state districts. For each week it finds the most senior call then in force; a right is out in that week exactly when that call is senior to it, which is why one line prices every right and juniors can be out while seniors keep diverting. “Majority out by” is the first week out in more than half the analog years. A frequency among named historical years, not a probability from a model, and not a forecast of what the division engineer will do. It says how often years whose flow resembled this one were under a call senior to this right in a given week. Snowpack, storage, and the actual administrative decisions of a given season are not modelled. Check the analog years listed: if they do not resemble this year to you, the outlook does not either.

Where it sits in line

Priority 1902-03-04 — 160th most senior of the 1815 structures with decreed rights in this water districtDWR's administrative subdivision of a river basin; the unit calls are usually stated in..

Under prior appropriationColorado's rule for sharing water: first in time, first in right. Age decides, not proximity or need., everything ahead of it in this line is satisfied in full before it receives any water. Immediately ahead: COORS B3(THUET MAUZ RES) (1902-03-04). Immediately behind: COORS B5 (1902-03-04).

On MAINSTEM at river mile 51.4, it is 63rd of 107 down the reach. Immediately upstream: COORS AUG STATION NO 1. Immediately downstream: COORS B3(THUET MAUZ RES).

Position on the modelled network, not a claim about whose water this is — a stream carries water from many rights at once, and diverted water returns to it.

Decreed rights (4)

Admin noDWR's numeric encoding of a water right's seniority. Smaller is more senior; the integer part counts days from 1849-12-31 to the date that ranks the right. AppropriatedWhen water was first put to beneficial use. It sets seniority unless a prior adjudication date is later. AdjudicatedWhen the water court confirmed the right. A use decreed in 1975 was not a decreed use in 1955, however old the appropriation is. AbsoluteA right actually put to use, as opposed to conditional -- a placeholder for a use not yet made. ConditionalA right reserving a place in line for a use not yet made; it must be diligently pursued or it lapses. Alt-pointAn absolute amount decreed at another structure that may be diverted here instead -- an alternate point of diversion or an exchange. DWR calls this the APEX amount; a right showing 0.0 absolute but an alt-point amount is exercised here under another structure's decree. Decreed forWhat the court said this water may be used for -- irrigation, municipal supply, augmentation and so on.Case
19055.00000 1902-03-041936-05-13 0.0 AF 0.0 6735.938 AF Irrigation, Municipal +8 96CW1117
43829.42307 1965-10-311970-12-31 1090.0 AF 0.0 — Irrigation, Municipal +8 88CW0206, 98CW0222
43829.43180 1968-03-221970-12-31 2645.0 AF 281.0 AF — Irrigation, Municipal +8 88CW0206, 98CW0222 +2
61322.00000 2017-11-222017-12-31 0.0 cfs 0.0 4.38 cfs Irrigation, Municipal +7 17CW3177

Amounts marked cfs are flow rates; AF are stored volumes (storage rights are decreed in acre-feet). An absolute amount of 0.0 beside an alt-point amount is not a dead right: the water is decreed at another structure, and that row records permission to divert it here instead (an alternate point or exchange). A case listing several numbers reflects the original decree plus later change cases.

Water-court filings naming this structure

1 application in the monthly water-court resumes explicitly reference this WDID. The resume is the earliest public notice of a new claim (C.R.S. 37-92-302) — years before anything reaches the decree record below. Most applications name structures by name rather than WDID, so absence here is weak evidence of absence.

MonthCaseWhat it asksOppose byExcerpt
2026-08 2026CW3134 reasonable diligence, exchange 2026-10-31 (17d left) CASE NUMBER 2026CW3134 (17CW3177). COORS BREWING COMPANY (“Coors”), PO Box 4030, 5th Floor BOC, Golden, Colorado 80401 -0030, (303) 277 -3342. April D. Hendricks and Peter D. Jaacks, Jewell Jimmerson Natural Resources La…

Source: Judicial Branch combined monthly resumes (archive), indexed nightly; WDIDs attached only when a 7-digit token in the filing matches DWR’s structure inventory.

How often is it out of priority?

Across the 11 seasons whose call record is complete enough to judge this structure (2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024, 2025, 2026), week by week from April.

most senior right · admin 19055.00000 · peaks at 11 of 11 seasons
AprMayJunJulAugSep
middle right · admin 43829.43180 · peaks at 11 of 11 seasons
AprMayJunJulAugSep
most junior right · admin 61322.00000 · peaks at 11 of 11 seasons
AprMayJunJulAugSep

Snow sets the clock here. In the driest third of snow years (3 seasons), the call was on all season, every season. In the middle third (5 seasons), the call settled in for the season around May 27; in 4 of them it never lifted at all. In the wettest third (3 seasons), the call settled in for the season around June 24 (June 17 to July 8 across those years).

Snow years ranked by the district’s April 1 snow-water percentile across 1 SNOTEL site; 11 seasons carry both a snow reading and a judgeable call record. How the past played out, not a forecast.

Why only 11 seasons, and what the bars mean

Each bar is one week: how many of those seasons that right was out of priority under a call this site can lawfully attribute to this structure. Green is never, red is every season on record.

The short record is a property of DWR's data, not of the river. A call only counts against a structure when we can establish it applies — by the districts named in its set comments, or by stream mile on the same source. DWR did not begin stating affected districts routinely until about 2015: fewer than one call in ten can be judged before then, against roughly two in three since. A season we cannot judge is not a season without calls, so it is dropped rather than counted as quiet — 12 seasons dropped here.

This is a frequency over past seasons, not a forecast. It says nothing about what the division engineer will do this year.

Recorded use (last 15 years on record)

Years far under the decreed amount? That gap has a name — paper water vs. wet water, explained on this structure.

In a median year this structure has a recorded diversion of 5,225 AF. Its most recent year on record, 2025, came in at 4,662 AF — 89% of that, and 3rd lowest of the 15 years with a recorded volume.

This structure records both diversions and reservoir releases — they are separate water movements and are accounted separately below.

YearDiverted (AFA volume: one acre covered a foot deep, about 326,000 gallons -- roughly a suburban household's outdoor use for a year.)Compared with its own recordReleased (AF)Days recordedPeak (cfs)
2011 7,443 15th lowest of 15 · 142% of median 1,944 302 62.5
2012 5,048 6th lowest of 15 · 97% of median 1,957 366 15.4
2013 5,565 13th lowest of 15 · 106% of median 1,538 365 78.4
2014 4,485 2nd lowest of 15 · 86% of median 1,922 364 45.3
2015 4,253 1st lowest of 15 · 81% of median 1,302 292 64.3
2016 4,679 4th lowest of 15 · 90% of median 1,732 293 81.8
2017 5,817 14th lowest of 15 · 111% of median 1,259 343 55.6
2018 5,387 10th lowest of 15 · 103% of median 1,503 365 57.0
2019 5,532 12th lowest of 15 · 106% of median 997 362 50.9
2020 4,722 5th lowest of 15 · 90% of median 804 359 44.3
2021 5,166 7th lowest of 15 · 99% of median 986 365 70.2
2022 5,225 8th lowest of 15 · 100% of median 1,031 365 20.3
2023 5,275 9th lowest of 15 · 101% of median 1,064 365 56.8
2024 5,484 11th lowest of 15 · 105% of median 1,131 359 67.7
2025 4,662 3rd lowest of 15 · 89% of median 1,055 295 52.4

How good is our record of it?

Grade A (10/10 points) — the components below are the finding; the letter alone is not.

The rubric, component by component
CheckStateDetail
identity complete name, type, and water source all on file
decreed rights on file 4 right(s), seniority decoded
diversion record current 6463 measured days, newest 335 day(s) before the data's end (DWR publishes ~1 year in arrears)
record continuity continuous 82% of the irrigation seasons in 1988-2025 carry measured days
published-record stability stable no upstream revisions recorded against this structure

Advisory reading aid on public data — not an administrative or legal conclusion, not a title opinion, and not a substitute for DWR administration or an engineer's analysis. Methodology review status is disclosed at hydrohistorian's basin pages.

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