Hydrohistorian
← My Water · All ditches in this district · Print / save as PDF ·
TAMARACK DITCH
Structure dossier · WDID 6400509 · DITCH · SOUTH PLATTE RIVER · DWR record
Where this page's figures come from
Generated 2026-09-05 08:09 by Hydrohistorian. Sources: DWR HydroBase snapshot HydroBase_CO_20260707 (history) + CDSS REST (current), USGS NWIS cross-checks. Engine v0.5.0 (93e2af1) — every figure regenerates from this named code version and data image.
In short
In a median year over its last 15 recorded years it diverts 853 acre-feet. It was a party to 1 court cases that also touched 8 other structures.
Assembled from the figures on this page — every number above is checked against them before it is shown (4 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 (diversion). 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.
Structures it shares court cases with
This structure was a party to 1 court case that also touched 8 other structures — changes of water right, augmentation plans, exchanges. Being parties to the same case does not by itself mean water moved between them; which way it ran, and how much, is in the decree.
| Case | Filed | Also touched |
|---|---|---|
W7713 |
— | DIV OF WILDLIFE AUG IMPACT REACH, TAMARACK WELL 10-21245F, TAMARACK WELL 4-47930-F, TAMARACK WELL 5-47931-F and 4 more |
Also a party to 1 omnibus
adjudication
(CA0944, 89 structures).
Those settled many rights at once and are listed separately: they say
these structures were adjudicated together, not that they deal with
each other.
How this is derived
Every court action DWR records for a structure
carries its case number. Where one case number appears in the records of
several structures, those structures were parties to the same proceeding.
This is read straight from the cached transaction tables — no
document was interpreted to build it. Case numbers are validated against
the known Colorado formats first: the case column also contains stray
dates (10/04/1884 appears on 98 Clear Creek rows), and
treating one as a case number would invent a shared proceeding between
60 unrelated structures. Cases spanning more than
12 structures are separated out as omnibus
adjudications. The filing year comes from the case number, not from the
row's adjudication date — that date belongs to the water right the
action describes, so a 2006 case legitimately carries a 1989 date.
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 853 AF. Its most recent year on record, 1992, came in at 60 AF — 7% of that, and 2nd 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) |
|---|---|---|---|---|
| 1958 | 436 | 6th lowest of 15 · 51% of median | 12 | 20.0 |
| 1973 | 268 | 4th lowest of 15 · 31% of median | 28 | 5.0 |
| 1974 | 179 | 3rd lowest of 15 · 21% of median | 11 | 20.0 |
| 1975 | 2,132 | 14th lowest of 15 · 250% of median | 93 | 25.0 |
| 1976 | 853 | 8th lowest of 15 · 100% of median | 19 | 35.0 |
| 1977 | 1,660 | 11th lowest of 15 · 195% of median | 39 | 50.0 |
| 1978 | 2,172 | 15th lowest of 15 · 255% of median | 53 | 25.0 |
| 1979 | 1,051 | 9th lowest of 15 · 123% of median | 19 | 40.0 |
| 1980 | 0 | 1st lowest of 15 · 0% of median | 2 | 0.0 |
| 1981 | 635 | 7th lowest of 15 · 74% of median | 31 | 20.0 |
| 1983 | 1,884 | 12th lowest of 15 · 221% of median | 39 | 25.0 |
| 1985 | 2,083 | 13th lowest of 15 · 244% of median | 54 | 20.0 |
| 1987 | 377 | 5th lowest of 15 · 44% of median | 20 | 10.0 |
| 1989 | 1,174 | 10th lowest of 15 · 138% of median | 38 | 19.0 |
| 1992 | 60 | 2nd lowest of 15 · 7% of median | 5 | 10.0 |
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 C (5/10 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 | 827 measured days; currency unknown (no data-coverage date to compare against) |
| record continuity | sparse | 9% of the irrigation seasons in 1950-1992 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.