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MAPLE GROVE RES

Structure dossier · WDID 0704411 · RESERVOIR · CLEAR CREEK · DWR record · probably CONSOLIDATED MUTUAL MAPLE GROVE’s (matched on DWR’s contact or an EPA intake name; verify below)

Maple Grove Res 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 2026-10-15 20:37 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

In short

MAPLE GROVE RES holds 45 decreed rights on CLEAR CREEK. No call currently reaches it that we can lawfully attribute, so none of its rights are being curtailed by one. 8 further calls state no district and sit outside this one, so they are counted here rather than assumed either way. In a median year over its last 15 recorded years it diverts 4,733 acre-feet. It was a party to 10 court cases that also touched 23 other structures.

Assembled from the figures on this page — every number above is checked against them before it is shown (6 checked). The detail, with its method, is in the cards below.

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

● In priority — no active call senior to this structure's rights affects its district (18 active call(s) checked).

8 further calls state no district and sit outside this one, so they are counted here rather than assumed either way.

Which of its rights are out of priority?

No active call verifiably reaches this structure (18 active call(s) checked), so none of its 45 rights is administratively curtailed today. (8 call(s) state no district and sit outside this one — not judged, not assumed.) In the 5 past years most like this one (2016, 2017, 2022, 2019, 2015), 3 of the rights shown below were out at least one week in at least one analog year.

Right (priority)NowAnalog years outMajority out by
1860-05-15 3788 — 0 of 5 —
1860-05-16 3789 — 0 of 5 —
1860-05-19 3792 — 0 of 5 —
… 39 more rights between these …
1988-11-03 50711 — 5 of 5 2026-10-01
1993-06-28 52596 — 5 of 5 2026-10-01
2009-07-31 58286 — 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 SLOUGH DITCH AUG STATION around 2026-10-01 (the newest reading on file) — currently 1434% of that gage's own median for this window — to pick the 5 most similar past years with complete administration records (2005–2026). 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 1860-05-15 — 23rd 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: FAIRMOUNT RES (1860-05-15). Immediately behind: LEE STEWART ESKINS DITCH (1860-05-16).

On MAINSTEM at river mile 52.7, it is 74th of 107 down the reach. Immediately upstream: SLOUGH DITCH AUG STATION. Immediately downstream: SWADLEY DITCH.

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 (49)

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
3788.00000 1860-05-151884-10-04 0.0 cfs 0.0 0.093 cfs Irrigation, Municipal +7 09CW0107, 13CW0017
3789.00000 1860-05-161884-10-04 0.0 cfs 0.0 0.001 cfs Municipal 12CW0303
3792.00000 1860-05-191884-10-04 0.0 AF 0.0 0.0351 AF Storage, Irrigation +8 02CW0226, 09CW0107 +3
3792.00000 1860-05-191884-10-04 0.0 cfs 0.0 0.1024 cfs Storage, Irrigation +8 02CW0226, 09CW0107 +3
3804.00000 1860-05-311884-10-04 0.0 cfs 0.0 0.2214 cfs Irrigation, Municipal +7 13CW0017, 09CW0107 +1
3818.00000 1860-06-141884-10-04 0.0 cfs 0.0 0.064 cfs Irrigation, Municipal +7 09CW0107, 13CW0017
3835.00000 1860-07-011884-10-04 0.0 cfs 0.0 0.0412 cfs Municipal 12CW0303
3896.00000 1860-08-311884-10-04 0.0 cfs 0.0 0.0065 cfs Municipal 12CW0303
4151.00000 1861-05-131884-10-04 0.0 AF 0.0 2.028 AF Storage, Irrigation +8 13CW0017, 02CW0226 +3
4151.00000 1861-05-131884-10-04 0.0 cfs 0.0 0.3719 cfs Storage, Irrigation +8 13CW0017, 02CW0226 +3
4152.00000 1861-05-141884-10-04 0.0 cfs 0.0 0.006 cfs Irrigation, Municipal +7 09CW0107, 13CW0017
4171.00000 1861-06-021884-10-04 0.0 cfs 0.0 0.064 cfs Irrigation, Municipal +7 13CW0017, 09CW0107
4180.00000 1861-06-111884-10-04 0.0 cfs 0.0 0.022 cfs Irrigation, Municipal +7 09CW0107, 13CW0017
4535.00000 1862-06-011884-10-04 0.0 cfs 0.0 0.041 cfs Irrigation, Municipal +7 94CW0036, 13CW0017 +2
4554.00000 1862-06-201884-10-04 0.0 cfs 0.0 0.0016 cfs Municipal 12CW0303
4896.00000 1863-05-281884-10-04 0.0 cfs 0.0 0.0017 cfs Municipal 12CW0303
4919.00000 1863-06-201884-10-04 0.0 cfs 0.0 0.0028 cfs Municipal 12CW0303
5295.00000 1864-06-301884-10-04 0.0 cfs 0.0 0.096 cfs Municipal 12CW0303
5538.00000 1865-02-281884-10-04 0.0 cfs 0.0 1.3571 cfs Municipal, All beneficial uses 94CW0036, 12CW0303
5592.00000 1865-04-231884-10-04 0.0 cfs 0.0 0.0071 cfs Municipal 12CW0303
5615.00000 1865-05-161884-10-04 0.0 cfs 0.0 0.0592 cfs Irrigation, Municipal +7 94CW0036, 12CW0303 +2
7449.00000 1870-05-241884-10-04 0.0 cfs 0.0 0.0003 cfs Municipal 12CW0303
7712.00000 1871-02-111884-10-04 0.0 AF 0.0 4.056 AF Storage, Irrigation +8 01CW0056, 02CW0226 +3
7712.00000 1871-02-111884-10-04 0.0 cfs 0.0 7.4399 cfs Storage, Irrigation +8 01CW0056, 02CW0226 +3
8127.00000 1872-04-011884-10-04 0.0 cfs 0.0 0.1593 cfs Municipal 12CW0303
9121.00000 1874-12-211884-10-04 0.0 cfs 0.0 5.775 cfs Irrigation, Municipal +7 09CW0107, 13CW0017
10184.00000 1877-11-181884-10-04 0.0 cfs 0.0 0.5981 cfs Municipal, All beneficial uses 94CW0036, 12CW0303
10546.00000 1878-11-151884-10-04 0.0 cfs 0.0 0.6174 cfs Municipal, All beneficial uses 94CW0036, 12CW0303
11647.00000 1881-11-201884-10-04 0.0 cfs 0.0 1.0594 cfs Municipal, All beneficial uses 94CW0036, 12CW0303
12136.00000 1883-03-241884-10-04 0.0 cfs 0.0 2.756 cfs Irrigation, Municipal +7 09CW0107, 13CW0017
13240.00000 1886-04-011895-10-09 0.0 cfs 0.0 0.1976 cfs Municipal 12CW0303
16549.00000 1895-04-231895-10-09 0.0 cfs 0.0 0.3475 cfs Municipal 12CW0303
16718.04932 1863-07-031936-05-13 0.0 AF 0.0 76.75 AF Irrigation, Domestic 99CW0208
16718.08127 1872-04-011936-05-13 0.0 cfs 0.0 0.2626 cfs Irrigation, Municipal 12CW0303
16718.10184 1877-11-181936-05-13 0.0 cfs 0.0 2.3439 cfs Municipal, All beneficial uses 94CW0036
16718.13224 1886-03-161936-05-13 0.0 cfs 0.0 1.2684 cfs Municipal, All beneficial uses 94CW0036
16718.13966 1888-03-271936-05-13 0.0 cfs 0.0 3.128 cfs Irrigation, Municipal +7 09CW0107, 13CW0017
16718.14107 1888-08-151936-05-13 43.6 AF 0.0 — Irrigation, Municipal +8 95CW0248
18415.00000 1900-06-021936-05-13 0.0 AF 0.0 3.744 AF Irrigation, Municipal +8 13CW0017, 81CW0424 +1
18415.00000 1900-06-021936-05-13 0.0 cfs 0.0 1.37 cfs Irrigation, Municipal +8 13CW0017, 81CW0424 +1
19055.00000 1902-03-041936-05-13 0.0 cfs 0.0 4.6196 cfs Irrigation 94CW0036
20281.00000 1905-07-121936-05-13 0.0 cfs 0.0 0.4811 cfs Municipal 12CW0303
43829.37963 1953-12-091970-12-31 621.0 AF 0.0 — Municipal, Domestic W0148
43829.38280 1954-10-221970-12-31 409.0 AF 0.0 — Municipal, Domestic W0147, 85CW0310 +2
48212.00000 1981-12-311981-12-31 0.0 cfs 0.0 5.0 cfs Irrigation, Other 81CW0424
49308.47135 1979-01-191985-12-31 72.0 AF 0.0 — Municipal, Domestic 85CW0417, 91CW0017
50711.00000 1988-11-031988-12-31 965.09 AF 106.91 AF — Irrigation, Municipal +7 88CW0224, 97CW0122 +2
52595.52409 1993-06-281994-12-31 0.0 cfs 0.0 5.0 cfs Storage, Irrigation +8 94CW0197, 03CW0351 +1
58286.00000 2009-07-312009-12-31 0.0 cfs 0.0 5.0 cfs All beneficial uses 09CW0107

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.

Filings that would move water above this headgate

2 water-court applications in the monthly resumes name a structure on CLEAR CREEK upstream of this headgate. A new right, exchange or change of use up there changes what arrives down here — the resume is the public notice, and the opposition window is how anyone affected answers it.

MonthCaseWhat it asksUpstream structuresOppose by
2026-08 2026CW3134 reasonable diligence, exchange COORS B5 (0.5 mi up), COORS B3(THUET MAUZ RES) (1.2 mi up), COORS IND D ALT PT 3 (1.6 mi up), COORS B2 (DUKES LAKES) (1.9 mi up) +2 more 2026-10-31 (16d)
2026-04 2026CW3066 — COORS IND D ALT PT 3 (1.6 mi up), COORS B2 (DUKES LAKES) (1.9 mi up), CROKE CANAL (2.9 mi up), ROCKY MOUNTAIN DITCH (2.9 mi up) +3 more 2026-06-30

Judged on this structure’s own named stream only — a filing on a tributary that joins upstream is not judged here. Filings that name structures only in prose, without a WDID, are invisible to this card. Reading aid, not legal advice; the deadline is computed from C.R.S. 37-92-302(3), and the court’s own notice controls.

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 3788.00000 · never out of priority in these seasons
AprMayJunJulAugSep
middle right · admin 9121.00000 · peaks at 11 of 11 seasons
AprMayJunJulAugSep
most junior right · admin 58286.00000 · 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 4,733 AF. Its most recent year on record, 2025, came in at 2,327 AF — 49% of that, and 2nd 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 5,157 10th lowest of 15 · 109% of median 4,417 359 48.3
2012 4,428 6th lowest of 15 · 94% of median 4,707 352 20.6
2013 4,307 4th lowest of 15 · 91% of median 3,849 365 184.6
2014 4,437 7th lowest of 15 · 94% of median 4,431 365 22.3
2015 5,062 9th lowest of 15 · 107% of median 5,645 364 38.2
2016 4,733 8th lowest of 15 · 100% of median 5,889 342 28.7
2017 2,150 1st lowest of 15 · 45% of median 5,168 275 28.4
2018 4,312 5th lowest of 15 · 91% of median 5,287 350 27.6
2019 4,202 3rd lowest of 15 · 89% of median 4,132 339 35.3
2020 7,829 12th lowest of 15 · 165% of median 4,569 359 58.3
2021 8,069 13th lowest of 15 · 170% of median 4,248 355 94.6
2022 7,668 11th lowest of 15 · 162% of median 4,306 365 66.4
2023 9,379 14th lowest of 15 · 198% of median 3,764 364 478.4
2024 9,838 15th lowest of 15 · 208% of median 4,887 306 133.0
2025 2,327 2nd lowest of 15 · 49% of median 3,854 184 21.1

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 49 right(s), seniority decoded
diversion record current 8536 measured days, newest 335 day(s) before the data's end (DWR publishes ~1 year in arrears)
record continuity continuous 100% of the irrigation seasons in 1992-2025 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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