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JOHNSON RESERVOIR
Structure dossier · WDID 3003707 · 3 · COAL GULCH · DWR record
Where this page's figures come from
Generated 2026-08-31 16:18 by Hydrohistorian. Sources: DWR HydroBase snapshot HydroBase_CO_20260707 (history) + CDSS REST (current), USGS NWIS cross-checks. Engine v0.5.0 (e1cc9aa) — every figure regenerates from this named code version and data image.
In short
In a median year over its last 14 recorded years it diverts 154 acre-feet.
Assembled from the figures on this page — every number above is checked against them before it is shown (2 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.
Which of its rights are out of priority?
Not computable for this structure: no decreed right on file, so there is no priority to test.
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 154 AF. Its most recent year on record, 2025, came in at 6 AF — 4% of that, and 2nd lowest of the 14 years with a recorded volume.
This structure records both diversions and reservoir releases — they are separate water movements and are accounted separately below.
| Year | Diverted (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 record | Released (AF) | Days recorded | Peak (cfs) |
|---|---|---|---|---|---|
| 2011 | 172 | 8th lowest of 14 · 112% of median | 244 | 122 | 7.5 |
| 2012 | 112 | 6th lowest of 14 · 73% of median | 259 | 90 | 3.5 |
| 2013 | 135 | 7th lowest of 14 · 88% of median | 192 | 93 | 3.6 |
| 2014 | 183 | 9th lowest of 14 · 119% of median | 159 | 62 | 3.5 |
| 2015 | 581 | 14th lowest of 14 · 378% of median | 144 | 92 | 4.9 |
| 2016 | 359 | 12th lowest of 14 · 234% of median | 159 | 88 | 8.8 |
| 2017 | 232 | 10th lowest of 14 · 151% of median | 179 | 179 | 10.7 |
| 2018 | — | no recorded volume | 230 | 0 | — |
| 2019 | 568 | 13th lowest of 14 · 370% of median | 184 | 94 | 11.7 |
| 2020 | 83 | 5th lowest of 14 · 54% of median | 334 | 89 | 5.4 |
| 2021 | 0 | 1st lowest of 14 · 0% of median | 293 | 103 | 0.0 |
| 2022 | 42 | 4th lowest of 14 · 27% of median | 264 | 365 | 2.2 |
| 2023 | 35 | 3rd lowest of 14 · 23% of median | 250 | 365 | 1.5 |
| 2024 | 249 | 11th lowest of 14 · 162% of median | 180 | 366 | 6.5 |
| 2025 | 6 | 2nd lowest of 14 · 4% of median | 196 | 304 | 0.5 |
Trends for this structure
Recorded use shows no clear trend over its last 14 recorded years — which is itself worth knowing.
How good is our record of it?
Grade C (6/10 points) — the components below are the finding; the letter alone is not.
The rubric, component by component
| Check | State | Detail |
|---|---|---|
| identity | complete | name, type, and water source all on file |
| decreed rights | absent | no water rights cached for this WDID |
| diversion record | present | 3803 measured days; currency unknown (no data-coverage date to compare against) |
| record continuity | patchy | 53% 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.