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OSBORNE CAYWOOD DITCH

Structure dossier · WDID 0400600 · DITCH · LITTLE THOMPSON RIVER · DWR record

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 2026-10-13 12:20 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
OSBORNE & CAYWOOD DITCH OSCDITCO 0.0 cfs 2011–2026, 5,505 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

0.0 cfs as of 2026-10-13 08:00 (4.3 h ago)

Zero is a real reading: the gage is reporting, and it says this structure is not diverting right now.

Provisional 15-minute telemetry from OSCDITCO ↗ (OSBORNE & CAYWOOD DITCH). 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

OSBORNE CAYWOOD DITCH holds 2 decreed rights on LITTLE THOMPSON RIVER. No active call senior to its rights reaches its district today (20 active calls checked), so it is in priority now. 7 further calls state no district and sit outside this one, so they are counted here rather than assumed either way. That is today's position; the weeks ahead cannot be projected for it: no gage record for this year at this date, so there is nothing to find analogs for. In a median year over its last 15 recorded years it diverts 648 acre-feet.

Assembled from the figures on this page — every number above is checked against them before it is shown (5 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

● In priority — no active call senior to this structure's rights affects its district (20 active call(s) checked).

7 further calls state no district and sit outside this one, so they are counted here rather than assumed either way.

Which of its rights are out of priority?

The outlook for the weeks ahead is not computable for this structure: no gage record for this year at this date, so there is nothing to find analogs for. Today’s position is a separate question, and it is answered in Current administration above — that screen reads the district’s active calls and needs no reference gage.

Where it sits in line

Priority 1861-06-01 — 1st most senior of the 1296 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 behind: BARNES DITCH (1861-11-10).

On LITTLE THOMPSON RIVER at river mile 49.5, it is 62nd of 97 down the reach. Immediately upstream: J B DITCH CO EAST. Immediately downstream: BOULDER LARIMER RES.

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 (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. 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
4170.00000 1861-06-011883-05-28 3.12 cfs 0.0 — Irrigation 05/28/1883
9200.00000 1875-03-101883-05-28 5.0 cfs 0.0 — Irrigation 05/28/1883, 84CW0204

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 8.12 cfs decreed rate, the average day over the last 6 year(s) had 6.839 cfs in priority (84% of the decree). No call in effect is a free river — that was 13.8% of days.

On 479 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 32 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 4.11 cfs 51% 1 0
2025 5.83 cfs 72% 40 0
2024 5.74 cfs 71% 114 0
2023 6.92 cfs 85% 65 0
2022 5.54 cfs 68% 31 0
2021 8.12 cfs 100% 1 0
Show the last 120 days, day by day
DateIn priorityControlling call
2026-10-12 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-10-11 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-10-10 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-10-09 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-10-08 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-10-07 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-10-06 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-10-05 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-10-04 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-10-03 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-10-02 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-10-01 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-30 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-29 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-28 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-27 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-26 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-25 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-24 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-23 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-22 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-21 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-20 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-19 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-18 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-17 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-16 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-15 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-14 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-13 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-12 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-11 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-10 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-09 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-08 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-07 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-06 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-05 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-04 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-03 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-02 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-09-01 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-31 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-30 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-29 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-28 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-27 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-26 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-25 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-24 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-23 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-22 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-21 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-20 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-19 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-18 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-17 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-16 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-15 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-14 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-13 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-12 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-11 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-10 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-09 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-08 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-07 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-06 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-05 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-04 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-03 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-02 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-08-01 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-31 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-30 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-29 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-28 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-27 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-26 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-25 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-24 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-23 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-22 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-21 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-20 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-19 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-18 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-17 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-16 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-15 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-14 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-13 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-12 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-11 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-10 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-09 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-08 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-07 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-06 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-05 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-04 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-03 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-02 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-07-01 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-06-30 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-06-29 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-06-28 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-06-27 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-06-26 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-06-25 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-06-24 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-06-23 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-06-22 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-06-21 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-06-20 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-06-19 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-06-18 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-06-17 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-06-16 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
2026-06-15 3.12 cfs (38%) OSBORNE CAYWOOD DITCH, 1861-06-01 · Little Thompson River · same source, at or above the calling point
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: 2955, of which 2838 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 4170.00000 · never out of priority in these seasons
AprMayJunJulAugSep
most junior right · admin 9200.00000 · peaks at 2 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 3; in 1 of them it never lifted at all. In the middle third (5 seasons), the call settled in for the season around June 24 (June 3 to July 8 across those years). In the wettest third (3 seasons), the call settled in for the season around July 15 (June 17 to July 15 across those years); in 1 of them it never lifted at all.

Snow years ranked by the district’s April 1 snow-water percentile across 2 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 648 AF. Its most recent year on record, 2025, came in at 403 AF — 62% of that, and 5th 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 1,066 14th lowest of 15 · 164% of median — 139 8.2
2012 506 7th lowest of 15 · 78% of median — 122 3.7
2013 389 3rd lowest of 15 · 60% of median — 109 4.3
2014 401 4th lowest of 15 · 62% of median — 63 6.2
2015 327 2nd lowest of 15 · 50% of median — 48 5.8
2016 648 8th lowest of 15 · 100% of median — 79 7.5
2017 884 13th lowest of 15 · 136% of median — 120 8.3
2018 181 1st lowest of 15 · 28% of median — 56 3.4
2019 1,203 15th lowest of 15 · 186% of median — 100 9.0
2020 417 6th lowest of 15 · 64% of median — 80 6.3
2021 764 12th lowest of 15 · 118% of median — 102 6.7
2022 656 9th lowest of 15 · 101% of median — 115 6.4
2023 687 11th lowest of 15 · 106% of median — 89 6.3
2024 673 10th lowest of 15 · 104% of median — 135 6.3
2025 403 5th lowest of 15 · 62% of median — 117 4.3

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
CheckStateDetail
identity complete name, type, and water source all on file
decreed rights on file 2 right(s), seniority decoded
diversion record current 8642 measured days, newest 389 day(s) before the data's end (DWR publishes ~1 year in arrears)
record continuity patchy 54% 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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