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OLIGARCHY DITCH

Structure dossier · WDID 0500547 · DITCH · SAINT VRAIN CREEK · DWR record

Oligarchy Ditch is a ditch on Saint Vrain Creek in Colorado. This page is its public record: the water it has a right to, whether it may take it today, and its history, compiled from the Colorado Division of Water Resources.

Source DWR administrative record · verify at DWR structure ↗ Source DWR administrative record · verify at DWR diversion records ↗ Source Our computation, scored against a reference · scored against DWR's call analysis, see /methods

Where this page's figures come from

Generated 2026-10-14 15:06 by Hydrohistorian. Sources: DWR HydroBase snapshot HydroBase_CO_20260928 (history) + CDSS REST (current), USGS NWIS cross-checks. Engine v0.5.0 (dd58e60) — every figure regenerates from this named code version and data image.

The record and the river

Where this structure is measured

GageFlowing nowRecordHow we know
OLIGARCHY DITCH DIVERSION OLIDITCO 51.22 cfs 2008–2026, 6,277 days DWR telemetry mapping

A green link is DWR's own: either its telemetry inventory maps this WDID to that station, or the station is named for this WDID (0700553 → 0700553A). An amber one is ours — the station sits within 250 m and shares a distinctive word with this structure's name, which is a strong hint rather than a DWR statement that this gage meters this structure. Wrong? Tell us.

Flowing now

51.22 cfs as of 2026-10-14 11:00 (4.1 h ago)

Provisional 15-minute telemetry from OLIDITCO ↗ (OLIGARCHY DITCH DIVERSION). Raw, not the approved record — it is never merged into the diversion history below. DWR publishes the official diversion record after the water year closes and is approved, which is why that record ends months back while this reads minutes ago.

In short

OLIGARCHY DITCH holds 29 decreed rights on SAINT VRAIN CREEK. As of 2026-09-27, 26 of them are out of priority under a call at admin 4488.00000 placed by CLOUGH/TRUE DITCH. Its 3 most senior rights, back to 1861-03-08, keep diverting. 7 further calls state no district and sit outside this one, so they are counted here rather than assumed either way. In a median year over its last 15 recorded years it diverts 7,982 acre-feet. It was a party to 13 court cases that also touched 27 other structures.

Assembled from the figures on this page — every number above is checked against them before it is shown (11 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.

Current administration

● Junior rights called out — call at SOUTH FLAT DITCH (SAINT VRAIN CREEK, priority 1864-01-01).

● Junior rights called out — call at CLOUGH/TRUE DITCH (SAINT VRAIN CREEK, priority 1862-04-14).

Which of its rights are out of priority?

Under today's controlling call (CLOUGH/TRUE DITCH, priority 1862-04-14): 26 of this structure's 29 rights are out of priority now. (7 call(s) state no district and sit outside this one — not judged, not assumed.) In the 5 past years most like this one (2021, 2013, 2020, 2010, 2012), 3 of the rights shown below were out at least one week in at least one analog year.

Right (priority)NowAnalog years outMajority out by
1861-03-08 4085 ● in priority 0 of 5 —
1862-03-20 4462 ● in priority 0 of 5 —
1862-04-15 4488 ● in priority 0 of 5 —
1862-05-15 4518 ● out 0 of 5 —
1862-10-01 4657 ● out 0 of 5 —
… 21 more rights between these …
1929-12-31 29219 ● out 4 of 5 2026-09-27
1986-10-28 49974 ● out 4 of 5 2026-09-27
2005-12-30 56977 ● out 4 of 5 2026-09-27
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 OLIGARCHY DITCH DIVERSION around 2026-09-27 (the newest reading on file) — currently 0% of that gage's own median for this window — to pick the 5 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 1861-03-08 — 21st most senior of the 1290 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: SMEAD DITCH (1861-03-08). Immediately behind: BECKWITH DITCH (1861-03-08).

On MAINSTEM at river mile 4.0, it is 223rd of 476 down the reach. Immediately upstream: DUPE WDID, SEE 0404159. Immediately downstream: GLODE POND.

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 (30)

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. Alt-pointAn absolute amount decreed at another structure that may be diverted here instead -- an alternate point of diversion or an exchange. DWR calls this the APEX amount; a right showing 0.0 absolute but an alt-point amount is exercised here under another structure's decree. Decreed forWhat the court said this water may be used for -- irrigation, municipal supply, augmentation and so on.Case
4085.00000 1861-03-081882-06-02 0.0 cfs 0.0 2.77 cfs Municipal, Augmentation +3 87CW0215
4462.00000 1862-03-201882-06-02 0.0 cfs 0.0 0.62 cfs Municipal, Augmentation +3 87CW0219
4488.00000 1862-04-151882-06-02 0.0 cfs 0.0 0.39 cfs Irrigation, Municipal +8 01CW0188
4518.00000 1862-05-151882-06-02 0.0 cfs 0.0 0.97 cfs Irrigation, Municipal +8 01CW0188
4657.00000 1862-10-011882-06-02 0.0 cfs 0.0 3.27 cfs Irrigation, Municipal +8 01CW0188
4853.00000 1863-04-151882-06-02 0.0 cfs 0.0 0.46 cfs Irrigation, Municipal +8 01CW0188
4883.00000 1863-05-151882-06-02 0.0 cfs 0.0 2.88 cfs Municipal, Augmentation +3 87CW0220
5295.00000 1864-06-301882-06-02 0.0 cfs 0.0 1.86 cfs Municipal, Augmentation +3 87CW0221
5600.00000 1865-05-011882-06-02 0.0 cfs 0.0 4.02 cfs Municipal, Augmentation +3 87CW0212
5631.00000 1865-06-011882-06-02 0.0 cfs 0.0 12.06 cfs Municipal, Augmentation +3 87CW0218
5996.00000 1866-06-011882-06-02 43.95 cfs 0.0 — Irrigation, Municipal +8 CA1335, 87CW0214 +3
6339.00000 1867-05-101882-06-02 0.0 AF 0.0 2804.6 AF Municipal 07CW0330
6339.00000 1867-05-101882-06-02 0.0 cfs 0.0 15.14 cfs Municipal 07CW0330
6756.00000 1868-06-301882-06-02 0.0 cfs 0.0 4.84 cfs Municipal 00CW0239
7012.00000 1869-03-131882-06-02 0.0 cfs 0.0 12.53 cfs Irrigation, Municipal +4 87CW0213, 00CW0241
7092.00000 1869-06-011882-06-02 0.0 cfs 0.0 2.77 cfs Municipal, Augmentation +3 87CW0218
7640.00000 1870-12-011882-06-02 98.65 cfs 0.0 — Irrigation, Municipal +8 CA1335, 81CW0361 +3
7822.00000 1871-06-011883-02-21 0.0 cfs 0.0 83.3 cfs All beneficial uses 87CW0231
8034.00000 1871-12-301882-06-02 0.0 cfs 0.0 3.36 cfs Municipal 00CW0239
8096.00000 1872-03-011882-06-02 36.84 cfs 0.0 — Irrigation CA1335
8464.00000 1873-03-041882-06-02 0.0 cfs 0.0 12.53 cfs Irrigation, Municipal +4 87CW0213, 00CW0241
8553.00000 1873-06-011882-06-02 0.0 cfs 0.0 16.05 cfs Municipal, Augmentation +3 87CW0216
8857.00000 1874-04-011882-06-02 58.07 cfs 0.0 — Irrigation CA1335
9953.00000 1877-04-011882-06-02 0.0 cfs 0.0 7.07 cfs Municipal 00CW0239
19271.00000 1902-10-061907-03-13 84.2 cfs 0.0 — Storage CA4790
19273.00000 1902-10-081907-03-13 171.2 cfs 0.0 — Storage CA4790
20890.19756 1904-02-031926-06-01 0.0 cfs 0.0 83.3 cfs All beneficial uses 87CW0231
29219.00000 1929-12-311951-07-23 171.2 cfs 0.0 — Storage CA11715
49974.00000 1986-10-281986-12-31 0.0 cfs 1000.0 cfs 112.0 cfs Storage, Municipal 86CW0394, 86CW0395
56977.00000 2005-12-302005-12-31 0.0 cfs 0.0 1561.0 cfs Augmentation, CUR +1 05CW0331

Amounts marked cfs are flow rates; AF are stored volumes (storage rights are decreed in acre-feet). An absolute amount of 0.0 beside an alt-point amount is not a dead right: the water is decreed at another structure, and that row records permission to divert it here instead (an alternate point or exchange). A case listing several numbers reflects the original decree plus later change cases.

How much of this decree was in priority, by day

A right is in priority on a day when it is senior to every call administering this structure. Of its 664.11 cfs decreed rate, the average day over the last 6 year(s) had 338.487 cfs in priority (51% of the decree). No call in effect is a free river — that was 12.3% of days.

On 1143 days some rights were in priority and others were not — seniority splits a decree rather than switching it off. Calls are set and released at a time of day, not at midnight, so a day is counted by the hour: a call setting at 4pm costs that day a third of its rate, not all of it. A call began or ended mid-day on 26 of these days.

This is paper water. It is the decreed rate that was in priority — not water that was physically in the stream, and not water this structure diverted. A ditch can be in priority for 50 cfs on a day the creek carries five. What that distinction means →

YearMean in priority (Apr–Sep) Share of decreeFree-river days Days fully out
2026 91.72 cfs 14% 1 107
2025 194.17 cfs 29% 39 38
2024 279.85 cfs 42% 92 30
2023 307.56 cfs 46% 60 17
2022 167.83 cfs 25% 31 47
2021 381.32 cfs 57% 1 18
Show the last 120 days, day by day
DateIn priorityControlling call
2026-10-13 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-10-12 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-10-11 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-10-10 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-10-09 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-10-08 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-10-07 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-10-06 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-10-05 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-10-04 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-10-03 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-10-02 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-10-01 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-30 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-29 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-28 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-27 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-26 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-25 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-24 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-23 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-22 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-21 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-20 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-19 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-18 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-17 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-16 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-15 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-14 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-13 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-12 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-11 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-10 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-09 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-08 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-07 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-06 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-05 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-04 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-03 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-02 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-09-01 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-31 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-30 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-29 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-28 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-27 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-26 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-25 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-24 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-23 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-22 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-21 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-20 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-19 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-18 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-17 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-16 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-15 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-14 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-13 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-12 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-11 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-10 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-09 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-08 0.0 cfs (0%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-07 59.813 cfs (9%) ZWECK TURNER DITCH, 1864-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-08-06 179.44 cfs (27%) SECTION NO 3 DITCH, 1873-09-26 · South Platte River · on a river this source flows into
2026-08-05 179.44 cfs (27%) SECTION NO 3 DITCH, 1873-09-26 · South Platte River · on a river this source flows into
2026-08-04 179.44 cfs (27%) SECTION NO 3 DITCH, 1873-09-26 · South Platte River · on a river this source flows into
2026-08-03 179.44 cfs (27%) SECTION NO 3 DITCH, 1873-09-26 · South Platte River · on a river this source flows into
2026-08-02 119.627 cfs (18%) NIWOT DITCH, 1865-06-01 · Saint Vrain Creek · same source, at or above the calling point
2026-08-01 0.0 cfs (0%) NIWOT DITCH, 1865-06-01 · Saint Vrain Creek · same source, at or above the calling point
2026-07-31 0.0 cfs (0%) NIWOT DITCH, 1865-06-01 · Saint Vrain Creek · same source, at or above the calling point
2026-07-30 59.813 cfs (9%) NIWOT DITCH, 1865-06-01 · Saint Vrain Creek · same source, at or above the calling point
2026-07-29 179.44 cfs (27%) SECTION NO 3 DITCH, 1873-09-26 · South Platte River · on a river this source flows into
2026-07-28 179.44 cfs (27%) SECTION NO 3 DITCH, 1873-09-26 · South Platte River · on a river this source flows into
2026-07-27 179.44 cfs (27%) SECTION NO 3 DITCH, 1873-09-26 · South Platte River · on a river this source flows into
2026-07-26 179.44 cfs (27%) SECTION NO 3 DITCH, 1873-09-26 · South Platte River · on a river this source flows into
2026-07-25 179.44 cfs (27%) SECTION NO 3 DITCH, 1873-09-26 · South Platte River · on a river this source flows into
2026-07-24 179.44 cfs (27%) SECTION NO 3 DITCH, 1873-09-26 · South Platte River · on a river this source flows into
2026-07-23 179.44 cfs (27%) SECTION NO 3 DITCH, 1873-09-26 · South Platte River · on a river this source flows into
2026-07-22 179.44 cfs (27%) SECTION NO 3 DITCH, 1873-09-26 · South Platte River · on a river this source flows into
2026-07-21 179.44 cfs (27%) SECTION NO 3 DITCH, 1873-09-26 · South Platte River · on a river this source flows into
2026-07-20 179.44 cfs (27%) SECTION NO 3 DITCH, 1873-09-26 · South Platte River · on a river this source flows into
2026-07-19 119.627 cfs (18%) NIWOT DITCH, 1865-06-01 · Saint Vrain Creek · same source, at or above the calling point
2026-07-18 0.0 cfs (0%) NIWOT DITCH, 1865-06-01 · Saint Vrain Creek · same source, at or above the calling point
2026-07-17 0.0 cfs (0%) NIWOT DITCH, 1865-06-01 · Saint Vrain Creek · same source, at or above the calling point
2026-07-16 0.0 cfs (0%) NIWOT DITCH, 1865-06-01 · Saint Vrain Creek · same source, at or above the calling point
2026-07-15 14.65 cfs (2%) NIWOT DITCH, 1865-06-01 · Saint Vrain Creek · same source, at or above the calling point
2026-07-14 43.95 cfs (7%) OLIGARCHY DITCH, 1866-06-01 · Saint Vrain Creek · same source, at or above the calling point
2026-07-13 43.95 cfs (7%) JAMES DITCH, 1868-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-07-12 43.95 cfs (7%) JAMES DITCH, 1868-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-07-11 43.95 cfs (7%) JAMES DITCH, 1868-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-07-10 43.95 cfs (7%) JAMES DITCH, 1868-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-07-09 43.95 cfs (7%) JAMES DITCH, 1868-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-07-08 43.95 cfs (7%) JAMES DITCH, 1868-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-07-07 43.95 cfs (7%) JAMES DITCH, 1868-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-07-06 108.47 cfs (16%) JAMES DITCH, 1868-06-30 · Saint Vrain Creek · same source, at or above the calling point
2026-07-05 237.51 cfs (36%) LOWER LATHAM DITCH, 1877-11-14 · South Platte River · on a river this source flows into
2026-07-04 237.51 cfs (36%) LOWER LATHAM DITCH, 1877-11-14 · South Platte River · on a river this source flows into
2026-07-03 237.51 cfs (36%) LOWER LATHAM DITCH, 1877-11-14 · South Platte River · on a river this source flows into
2026-07-02 237.51 cfs (36%) LOWER LATHAM DITCH, 1877-11-14 · South Platte River · on a river this source flows into
2026-07-01 237.51 cfs (36%) LOWER LATHAM DITCH, 1877-11-14 · South Platte River · on a river this source flows into
2026-06-30 237.51 cfs (36%) LOWER LATHAM DITCH, 1877-11-14 · South Platte River · on a river this source flows into
2026-06-29 237.51 cfs (36%) LOWER LATHAM DITCH, 1877-11-14 · South Platte River · on a river this source flows into
2026-06-28 237.51 cfs (36%) HARMONY DITCH 1, 1897-05-03 · South Platte River · on a river this source flows into
2026-06-27 237.51 cfs (36%) HARMONY DITCH 1, 1897-05-03 · South Platte River · on a river this source flows into
2026-06-26 237.51 cfs (36%) LOWER LATHAM DITCH, 1877-11-14 · South Platte River · on a river this source flows into
2026-06-25 237.51 cfs (36%) LOWER LATHAM DITCH, 1877-11-14 · South Platte River · on a river this source flows into
2026-06-24 237.51 cfs (36%) LOWER LATHAM DITCH, 1877-11-14 · South Platte River · on a river this source flows into
2026-06-23 237.51 cfs (36%) LOWER LATHAM DITCH, 1877-11-14 · South Platte River · on a river this source flows into
2026-06-22 237.51 cfs (36%) LOWER LATHAM DITCH, 1877-11-14 · South Platte River · on a river this source flows into
2026-06-21 237.51 cfs (36%) LOWER LATHAM DITCH, 1877-11-14 · South Platte River · on a river this source flows into
2026-06-20 237.51 cfs (36%) LOWER LATHAM DITCH, 1877-11-14 · South Platte River · on a river this source flows into
2026-06-19 237.51 cfs (36%) LOWER LATHAM DITCH, 1877-11-14 · South Platte River · on a river this source flows into
2026-06-18 237.51 cfs (36%) LOWER LATHAM DITCH, 1877-11-14 · South Platte River · on a river this source flows into
2026-06-17 237.51 cfs (36%) LOWER LATHAM DITCH, 1877-11-14 · South Platte River · on a river this source flows into
2026-06-16 237.51 cfs (36%) LOWER LATHAM DITCH, 1877-11-14 · South Platte River · on a river this source flows into
How this is worked out, and what it cannot tell you
  • This is a decreed rate that was in priority -- paper water, not water that was available or diverted.
  • Augmentation plans, exchanges and substitute supply plans let a structure divert lawfully while out of priority; none are modelled.
  • Calls on the river this source flows into are included without a position test, so curtailment can be over-reported where the calling point sits above the confluence.
  • DWR's administration is the authority. Scored against DWR's own call analysis, this method agreed on 95.5% of 85,822 structure-days (2026-08-29).
  • Calls considered for this structure: 3349, of which 2844 sit on a river it flows into.

How often is it out of priority?

Across the 11 seasons whose call record is complete enough to judge this structure (2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024, 2025, 2026), week by week from April.

most senior right · admin 4085.00000 · never out of priority in these seasons
AprMayJunJulAugSep
middle right · admin 7092.00000 · peaks at 10 of 11 seasons
AprMayJunJulAugSep
most junior right · admin 56977.00000 · peaks at 11 of 11 seasons
AprMayJunJulAugSep

Snow sets the clock here. In the driest third of snow years (3 seasons), the call settled in for the season around June 17 (June 3 to June 17 across those years). In the middle third (5 seasons), the call settled in for the season around June 24 (June 17 to June 24 across those years); in 3 of them it never lifted at all. In the wettest third (3 seasons), the call settled in for the season around July 8 (June 17 to July 8 across those years).

Snow years ranked by the district’s April 1 snow-water percentile across 3 SNOTEL sites; 11 seasons carry both a snow reading and a judgeable call record. How the past played out, not a forecast.

Why only 11 seasons, and what the bars mean

Each bar is one week: how many of those seasons that right was out of priority under a call this site can lawfully attribute to this structure. Green is never, red is every season on record.

The short record is a property of DWR's data, not of the river. A call only counts against a structure when we can establish it applies — by the districts named in its set comments, or by stream mile on the same source. DWR did not begin stating affected districts routinely until about 2015: fewer than one call in ten can be judged before then, against roughly two in three since. A season we cannot judge is not a season without calls, so it is dropped rather than counted as quiet — 12 seasons dropped here.

This is a frequency over past seasons, not a forecast. It says nothing about what the division engineer will do this year.

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 7,982 AF. Its most recent year on record, 2025, came in at 8,458 AF — 106% of that, and 9th 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.

YearDiverted (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 recordReleased (AF)Days recordedPeak (cfs)
2011 5,312 2nd lowest of 15 · 66% of median — 183 35.1
2012 3,904 1st lowest of 15 · 49% of median — 160 48.1
2013 10,785 13th lowest of 15 · 135% of median — 184 82.9
2014 5,829 4th lowest of 15 · 73% of median — 192 39.4
2015 5,692 3rd lowest of 15 · 71% of median — 155 74.6
2016 6,092 6th lowest of 15 · 76% of median — 200 57.7
2017 11,616 14th lowest of 15 · 146% of median — 167 110.5
2018 5,950 5th lowest of 15 · 74% of median — 203 45.2
2019 9,995 11th lowest of 15 · 125% of median — 265 71.4
2020 10,012 12th lowest of 15 · 125% of median — 252 68.1
2021 12,005 15th lowest of 15 · 150% of median — 212 93.4
2022 9,468 10th lowest of 15 · 119% of median — 179 80.9
2023 7,982 8th lowest of 15 · 100% of median — 190 71.3
2024 6,476 7th lowest of 15 · 81% of median — 179 34.7
2025 8,458 9th lowest of 15 · 106% of median — 168 70.7

Call-derived yield: senior right divertible 100.0% of a median season / 84.1% dry-year.

How good is our record of it?

Grade A (10/10 points) — the components below are the finding; the letter alone is not.

The rubric, component by component
CheckStateDetail
identity complete name, type, and water source all on file
decreed rights on file 30 right(s), seniority decoded
diversion record current 14379 measured days, newest 331 day(s) before the data's end (DWR publishes ~1 year in arrears)
record continuity continuous 89% 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.

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