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DILLON RESERVOIR
Structure dossier · WDID 3604512 · 3 · BLUE RIVER · DWR record
Where this page's figures come from
Generated 2026-08-28 00:58 by Hydrohistorian. Sources: DWR HydroBase snapshot HydroBase_CO_20260707 (history) + CDSS REST (current), USGS NWIS cross-checks. Engine v0.5.0 (2deb1d7) — every figure regenerates from this named code version and data image.
Where it sits
Location as DWR records it. Faint dots are the neighbouring water; click any to open it.
Which of its rights are out of priority?
Not computable for this structure: this structure is not on the modelled flow network, so no reference gage can honestly stand in for it.
Where it sits in line
Priority 1895-05-01 — 154th most senior of the 1247 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: BUFFALO DITCH (1895-05-01). Immediately behind: F W S DITCH (1895-06-15).
Decreed rights (21)
| 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. | Units | UsesWhat the court said this water may be used for -- irrigation, municipal supply, augmentation and so on. | Case |
|---|---|---|---|---|---|---|---|
| 16557.0 | 1895-05-01 | 1910-03-02 | 0.0 | 0.0 | C | IRRMUNINDRECDOMOTH | |
| 22965.22553 | 1911-10-01 | 1913-10-13 | 0.0 | 0.0 | C | AUG | 194 |
| 25780.0 | 1920-08-01 | 1952-03-10 | 0.0 | 0.0 | C | IRRMUNCOMRECFIRDOMAUG | 329 |
| 25780.0 | 1920-08-01 | 1952-03-10 | 0.0 | 0.0 | A | IRRMUNCOMRECFIRDOMAUG | 329 |
| 32075.24411 | 1916-11-01 | 1952-03-10 | 0.0 | 0.0 | C | IRRMUNINDRECDOMOTH | |
| 32075.2578 | 1920-08-01 | 1952-03-10 | 0.0 | 0.0 | A | AUG | 329 |
| 32075.2578 | 1920-08-01 | 1952-03-10 | 0.0 | 0.0 | C | AUG | 329 |
| 32075.2651 | 1922-08-01 | 1952-03-10 | 0.0 | 0.0 | C | IRRMUNINDRECDOMOTH | |
| 35238.0 | 1946-06-24 | 1952-03-10 | 252678.0 | 0.0 | A | MUNOTH | 8 |
| 36437.0 | 1949-10-05 | 1952-03-10 | 0.0 | 0.0 | C | IRRMUNINDRECDOMOTH | |
| 47602.0 | 1980-04-30 | 1987-12-31 | 0.0 | 0.0 | A | MUNAUG | |
| 47602.0 | 1980-04-30 | 1987-12-31 | 0.0 | 0.0 | C | MUNAUG | |
| 50038.49309 | 1985-01-01 | 1987-12-31 | 182522.0 | 0.0 | A | MUN | |
| 57688.0 | 2007-12-11 | 2007-12-31 | 0.0 | 0.0 | A | MUNCOMINDRECFISFIRDOMAUGEVPOTH | |
| 57688.0 | 2007-12-11 | 2007-12-31 | 0.0 | 0.0 | C | MUNCOMINDRECFISFIRDOMAUGEVPOTH | |
| 57708.57688 | 2007-12-11 | 2008-12-31 | 0.0 | 0.0 | A | IRRMUNCOMRECFIRDOMAUG | |
| 57708.57688 | 2007-12-11 | 2008-12-31 | 0.0 | 0.0 | C | IRRMUNCOMRECFIRDOMAUG | |
| 58804.48692 | 1983-04-25 | 2011-12-31 | 0.0 | 0.0 | A | IRRMUNFIRDOM | |
| 58804.48692 | 1983-04-25 | 2011-12-31 | 0.0 | 0.0 | C | IRRMUNFIRDOM | |
| 58804.4956 | 1985-09-09 | 2011-12-31 | 0.0 | 0.0 | C | IRRMUNFIRDOM | |
| 58804.4956 | 1985-09-09 | 2011-12-31 | 0.0 | 0.0 | A | IRRMUNFIRDOM |
Legal record & documents
23 decreed actions on record across
15 court cases:
11CW0021, 17CW3114, 07CW0232, 87CW0376, 87CW0218, 20CW3088, 03CW0039, 81CW0353, 09CW0153, W0741 and 5 more below.
Every case, dated
| Case | Actions | Latest adjudication | Types |
|---|---|---|---|
11CW0021 | 2 | 2011-12-31 | S |
17CW3114 | 1 | 2008-12-31 | S |
07CW0232 | 2 | 2007-12-31 | S |
87CW0376 | 2 | 1987-12-31 | S |
87CW0218 | 2 | 1987-12-31 | O |
20CW3088 | 1 | 1987-12-31 | S |
03CW0039 | 1 | 1987-12-31 | S |
81CW0353 | 1 | 1981-12-31 | S |
09CW0153 | 1 | 1981-12-31 | S |
W0741 | 1 | 1952-03-10 | S |
CA1806 | 1 | 1952-03-10 | S |
92CW0292 | 1 | 1952-03-10 | S |
87CW0257 | 2 | 1952-03-10 | S |
85CW0026 | 4 | 1952-03-10 | O, S |
08CW0016 | 1 | 1952-03-10 | O |
DWR's own records for this structure: net amounts · transactions & adjudication history · scanned decrees (search a case number there for the imaged document). On this site: the district's full legal picture →
Recorded use (last 15 years on record)
In a median year this structure has a recorded diversion of 59,703 AF. Its most recent year on record, 2024, came in at 51,061 AF — 86% of that, and 6th 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.
| 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) |
|---|---|---|---|---|---|
| 2010 | 39,491 | 2nd lowest of 15 · 66% of median | 53,779 | 365 | 778.0 |
| 2011 | 88,827 | 11th lowest of 15 · 149% of median | 62,649 | 365 | 1201.0 |
| 2012 | 76,057 | 10th lowest of 15 · 127% of median | 129,451 | 366 | 413.0 |
| 2013 | 129,112 | 15th lowest of 15 · 216% of median | 71,337 | 304 | 1688.0 |
| 2014 | 1,527 | 1st lowest of 15 · 3% of median | 1,109 | 31 | 89.0 |
| 2015 | 51,536 | 7th lowest of 15 · 86% of median | 26,412 | 285 | 1408.0 |
| 2016 | 42,501 | 3rd lowest of 15 · 71% of median | 44,585 | 366 | 973.2 |
| 2017 | 59,703 | 8th lowest of 15 · 100% of median | 41,191 | 308 | 1010.3 |
| 2018 | 46,061 | 4th lowest of 15 · 77% of median | 99,757 | 275 | 775.8 |
| 2019 | 99,324 | 13th lowest of 15 · 166% of median | 51,680 | 365 | 1441.3 |
| 2020 | 50,598 | 5th lowest of 15 · 85% of median | 53,577 | 366 | 549.4 |
| 2021 | 111,958 | 14th lowest of 15 · 188% of median | 92,486 | 365 | 1040.6 |
| 2022 | 91,591 | 12th lowest of 15 · 153% of median | 68,548 | 365 | 1062.4 |
| 2023 | 63,194 | 9th lowest of 15 · 106% of median | 50,968 | 365 | 1085.7 |
| 2024 | 51,061 | 6th lowest of 15 · 86% of median | 55,408 | 305 | 791.6 |
Trends for this structure
Recorded use shows no clear trend over its last 15 recorded years — which is itself worth knowing.
How good is our record of it?
Grade A (9/10 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 | on file | 21 right(s), seniority decoded |
| diversion record | present | 12012 measured days; currency unknown (no data-coverage date to compare against) |
| record continuity | continuous | 100% of the irrigation seasons in 1974-2024 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.