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MCCARTY DITCH
Structure dossier · WDID 0600542 · DITCH · BOULDER CREEK · DWR record
Where this page's figures come from
Generated 2026-08-28 02:38 by Hydrohistorian. Sources: DWR HydroBase snapshot HydroBase_CO_20260707 (history) + CDSS REST (current), USGS NWIS cross-checks. Engine v0.5.0 (5cd37f7) — 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.
Current administration
● Fully called out — call at RURAL DITCH (BOULDER CREEK, priority 1862-05-09).
● Fully called out — call at JONES DONNELLY DITCH (SOUTH BOULDER CREEK, priority 1860-04-30).
● Fully called out — call at HOWARD DITCH (SOUTH BOULDER CREEK, priority 1860-04-01).
Which of its rights are out of priority?
Under today's controlling call (HOWARD DITCH, priority 1860-04-01): 1 of this structure's 1 rights are out of priority now. (8 call(s) state no district and sit outside this one — not judged, not assumed.) In the 4 past years most like this one (2024, 2022, 2025, 2023), 1 of the rights shown below were out at least one week in at least one analog year.
| Right (priority) | Now | Analog years out | Majority out by |
|---|---|---|---|
| 1862-06-01 4535 | ● out | 4 of 4 | 2026-09-02 |
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 BOULDER CREEK BELOW BROADWAY STREET around 2026-08-26 (the newest reading on file) — currently 68% of that gage's own median for this window — to pick the 4 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 1862-06-01 — 57th most senior of the 1867 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: 0600530 (1862-06-01). Immediately behind: NORTH BOULDER FARMERS DITCH (1862-06-01).
On MAINSTEM at river mile 9.2, it is 9th of 78 down the reach. Immediately upstream: BOULDER WHITE ROCK DITCH. Immediately downstream: NORTH BOULDER FARMERS 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 (1)
| 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 |
|---|---|---|---|---|---|---|---|
| 4535.0 | 1862-06-01 | 1882-06-02 | 2.465 | 0.0 | C | IRR |
Legal record & documents
5 decreed actions on record across
3 court cases:
W7570, 90CW0193, 06/02/1882.
Every case, dated
| Case | Actions | Latest adjudication | Types |
|---|---|---|---|
W7570 | 2 | 1882-06-02 | O |
90CW0193 | 2 | 1882-06-02 | O |
06/02/1882 | 1 | 1882-06-02 | 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 149 AF. Its most recent year on record, 2025, came in at 170 AF — 114% of that, and 9th lowest of the 15 years with a recorded volume.
| 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 | Days recorded | Peak (cfs) |
|---|---|---|---|---|
| 1970 | 119 | 6th lowest of 15 · 80% of median | 47 | 2.0 |
| 1971 | 32 | 2nd lowest of 15 · 22% of median | 26 | 1.0 |
| 1972 | 18 | 1st lowest of 15 · 12% of median | 12 | 1.0 |
| 1973 | 121 | 7th lowest of 15 · 81% of median | 66 | 1.0 |
| 1986 | 567 | 15th lowest of 15 · 380% of median | 144 | 2.0 |
| 1987 | 484 | 14th lowest of 15 · 325% of median | 123 | 2.0 |
| 1988 | 478 | 13th lowest of 15 · 321% of median | 124 | 3.0 |
| 2014 | 274 | 11th lowest of 15 · 184% of median | 93 | 1.5 |
| 2018 | 59 | 4th lowest of 15 · 40% of median | 45 | 0.9 |
| 2019 | 55 | 3rd lowest of 15 · 37% of median | 42 | 1.0 |
| 2020 | 99 | 5th lowest of 15 · 66% of median | 67 | 1.0 |
| 2021 | 149 | 8th lowest of 15 · 100% of median | 62 | 1.5 |
| 2022 | 307 | 12th lowest of 15 · 206% of median | 152 | 1.7 |
| 2024 | 231 | 10th lowest of 15 · 155% of median | 145 | 1.2 |
| 2025 | 170 | 9th lowest of 15 · 114% of median | 98 | 1.1 |
Trends for this structure
Recorded use shows no clear trend over its last 15 recorded years — which is itself worth knowing.
Its reference gage, BOULDER CREEK BELOW BROADWAY STREET: no clear flow trend.
How good is our record of it?
Grade B (8/10 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 | 1 right(s), seniority decoded |
| diversion record | current | 1960 measured days, newest 332 day(s) before the data's end (DWR publishes ~1 year in arrears) |
| record continuity | sparse | 12% of the irrigation seasons in 1950-2025 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.