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NAIRN DITCH
Structure dossier · WDID 4700787 · 1 · LITTLE GRIZZLY CREEK · DWR record
Where this page's figures come from
Generated 2026-08-27 23:44 by Hydrohistorian. Sources: DWR HydroBase snapshot HydroBase_CO_20260707 (history) + CDSS REST (current), USGS NWIS cross-checks. Engine v0.5.0 (a1c9146) — 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 1885-05-01 — 41st most senior of the 1262 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: MATHEWS DITCH (1885-05-01). Immediately behind: DONELSON DITCH (1885-05-04).
Decreed rights (2)
| 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 |
|---|---|---|---|---|---|---|---|
| 12905.0 | 1885-05-01 | 1892-09-19 | 14.5 | 0.0 | C | IRR | 15 |
| 33534.29477 | 1930-09-15 | 1958-01-10 | 20.0 | 0.0 | C | IRR | 759 |
Legal record & documents
2 decreed actions on record across
2 court cases:
CA0511, CA0922.
Every case, dated
| Case | Actions | Latest adjudication | Types |
|---|---|---|---|
CA0511 | 1 | 1958-01-10 | S |
CA0922 | 1 | 1892-09-19 | 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 1,587 AF. Its most recent year on record, 2024, came in at 0 AF — 0% of that, and 1st 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) |
|---|---|---|---|---|
| 2004 | 2,652 | 14th lowest of 15 · 167% of median | 87 | 25.0 |
| 2005 | 2,458 | 13th lowest of 15 · 155% of median | 70 | 30.0 |
| 2006 | 2,293 | 11th lowest of 15 · 144% of median | 82 | 20.0 |
| 2007 | 1,920 | 10th lowest of 15 · 121% of median | 46 | 32.0 |
| 2008 | 1,587 | 8th lowest of 15 · 100% of median | 36 | 30.4 |
| 2009 | 1,207 | 4th lowest of 15 · 76% of median | 51 | 20.0 |
| 2010 | 1,459 | 6th lowest of 15 · 92% of median | 47 | 27.5 |
| 2012 | 427 | 2nd lowest of 15 · 27% of median | 131 | 4.5 |
| 2013 | 1,378 | 5th lowest of 15 · 87% of median | 72 | 12.0 |
| 2014 | 988 | 3rd lowest of 15 · 62% of median | 49 | 11.7 |
| 2015 | 2,874 | 15th lowest of 15 · 181% of median | 49 | 43.4 |
| 2017 | 1,525 | 7th lowest of 15 · 96% of median | 113 | 7.9 |
| 2018 | 1,628 | 9th lowest of 15 · 103% of median | 78 | 12.1 |
| 2019 | 2,368 | 12th lowest of 15 · 149% of median | 53 | 45.0 |
| 2024 | 0 | 1st lowest of 15 · 0% of median | 1 | 0.0 |
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 B (7/10 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 | 2 right(s), seniority decoded |
| diversion record | present | 2880 measured days; currency unknown (no data-coverage date to compare against) |
| record continuity | sparse | 24% of the irrigation seasons in 1969-2024 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.