Lower Uncompahgre River

Division 4 · Water District 41

Auto-mapped

Lower Uncompahgre River on the ground — the ditches, wells, reservoirs and gages of Water District 41 · clicktap anything for its record

The drilled-depth cells in view, as a table

Each row is one ~3-mile cell (0.04°): the median of the depths drillers filed for the wells spotted inside it, and how many wells that median stands on. Cells with fewer than five filed depths are left blank on the map and out of this table. This is the driller’s own number, filed once when the well was drilled; it says how deep wells here typically go, not where the water table is and not whether wells are getting deeper. Spotting is the file’s own, about a mile at best.

Lat	Lon	Median drilled depth, ft	Wells with a depth

Browse this district’s ditches, gages, reservoirs, wells and springs as a list.

5% of normal flow, week of 2026-06-29

26 calls active on it right now

The Uncompahgre River is critically low for late June -- 5% of normal flow, its 4th-driest such week in 88 years of record. 26 calls stand against it right now; the most senior right calling dates to 1878.

Full diagnostic snapshot pending — this district's weekly-style report (system status, active calls, hydrographs, anomaly flags) is produced by the nightly rotation and appears here after its first run. The tabs above are live now.

Reconstruct conditions as of

Evolution of the network

This year, in context

In the weeks around 2026-07-06 (the newest reading on file), flows at the 28 ranked gages are running at a median 80% of their own long-term norm for this window — 19 below a typical year, 9 at or above. Driest relative to its record: UNCOMPAHGRE RIVER NEAR OLATHE, ranking 2nd lowest of 36 years.

How this comparison is made

Each gage's mean flow over the 3 days either side of 2026-07-06, compared with the same window in every year of its own record — so a gage is only ever measured against itself, and gages with no record in the window are counted out rather than guessed.

Gage flow trend & changepoints

What counts as a trend here

Computed 2026-08-30 20:00 from 30 gage(s) with cached period-of-record data. The series is each gage's annual mean flow in cfs (years with ≥300 days of record). Mann-Kendall (trend, with the Hamed–Rao correction for serial correlation — persistence can otherwise fake significance) and Pettitt (changepoint) both require at least 8 years spanning at least 10 years of record. A gage below that reports no signal — which is not the same as “no change.” The %-per-decade figure is the same Sen slope divided by the gage's median annual flow, for comparing across streams of very different size; it is omitted for near-ephemeral channels where the median is too small to divide by honestly.

Of the 30 gages with enough record, 1 is trending down and 2 up, and 3 carry a detected shift. The clearest is South Canal near Montrose, its annual mean flow changing +54.57 cfs per decade (+11.7% of its median annual flow) over 36 years (p<0.0001). The other 27 show no clear signal either way.

Drought history, cost, and the four-century context moved to the Drought tab.

Gage	Trend	Change / decade cfs · % of median annual flow	Significance	Years	Changepoint
▸ South Canal near Montrose SOUCANCO	↑ increasing	+54.57 cfs +11.7%	p<0.001	36	~2008
▸ Abc Lateral ABCLATCO	↓ decreasing	-15.84 cfs -29.1%	p<0.001	37	~2007
▸ Fairview Inlet Off the South Canal near Montrose FAIRVWCO	↑ increasing	+0.70 cfs +5.6%	p=0.009	24	~2016

27 other gage(s) show no significant trend or changepoint (not shown).

How the measurement network itself changed

This basin was not always measured the way it is today — the API-era record is dense and recent, the early record sparse. 28 gage(s) and 61 structure(s) report in 2026, but structure reporting only reached half its modern level around ~1950. Every historical claim below is checked against this: long-term shifts that co-move with the growth of the network carry an explicit measurement-evolution caution, and abandonment screens whose idleness begins before the modern reporting era are flagged †.

Decade	Gages with data (median yr)	Structures reporting (median yr)
1900s	0	1
1930s	1	2
1940s	1	0
1950s	1	57
1960s	1	70
1970s	1	74
1980s	1	72
1990s	4	68
2000s	5	52
2010s	15	63
2020s	23	61

Mass-balance (network closure) trend

Structure divrec-history backfill coverage as of the last check: 6% of 1324 schematic-relevant structures. 0 year(s) clear the 30% coverage gate so far -- the trend activates automatically once qualifying years span a full decade. No action needed; the nightly backfill keeps extending the record.

Reach gain/loss shifts (1991–2026)

Mass-balance kinks computed for every summer month back to 1991 (854 reach-snapshots) — which reaches gain or lose water, and how that has shifted across decades. Each shift is cross-checked against the observation record above: as more diversions became metered, "unaccounted" water shrinks mechanically, which can masquerade as a hydrologic shift.

FAIRVIEW INLET OFF THE SOUTH CANAL NEAR MONTROSE: reach shifted from -350 cfs to -95 cfs summer mean (more gaining, p=0.011, 17 yr) [alluvial valley: real alluvial aquifer -- a decades-long shift toward losing is the classic signature of alluvial pumping and urbanization] [1 alluvial wells within 2 mi of the gage; pooled water table -0.5 ft (2014–2024, decreasing)]
GARNET DITCH: reach shifted from -63 cfs to -18 cfs summer mean (more gaining, p=0.000, 16 yr) [alluvial valley: real alluvial aquifer -- a decades-long shift toward losing is the classic signature of alluvial pumping and urbanization] [measurement-evolution caution: this shift co-moves with the growth of the gage/metering network (rho=-0.69) -- part of it may be unaccounted water becoming accounted, not hydrologic change] [3 alluvial wells within 2 mi of the gage; pooled water table -0.3 ft (2014–2024, no_trend)]
IRONSTONE CANAL NEAR OLATHE, CO: reach shifted from +124 cfs to +164 cfs summer mean (more gaining, p=0.010, 16 yr) [alluvial valley: real alluvial aquifer -- a decades-long shift toward losing is the classic signature of alluvial pumping and urbanization] [3 alluvial wells within 2 mi of the gage; pooled water table +1.2 ft (1976–2024, no_trend)]

Groundwater now has its own tab: 76 monitored well(s), water-table trends, stream corridors, and the advisory depletion screen.

Reservoirs now has its own tab: 3 reservoir(s), end-of-year storage back to 1950, click-to-chart histories.

Cross-gage pattern fingerprint

Over the 35-year window with full coverage (1992–2026), the dominant shared pattern across 3 gage(s) explains 67% of year-to-year variance (almost certainly a basin-wide climate/snowpack driver).

ABCLATCO doesn't move with that shared pattern -- a real, localized signal (a new diversion, land-use change, or a gage-specific data problem) worth a closer look, not necessarily noise.

Structures most implicated by reconciliation (as of 2026-07-06)

Which structures' data absorbed the most correction when the current mass-balance snapshot was reconciled -- see the Historical tab for the full picture on any date.

ISOM SPRING AND PIPELINE NO1 (return): +5.3 cfs (6% of that reach's correction)
ISOM POND NO1 (diversion): +5.3 cfs (6% of that reach's correction)
ISOM SPRING NO3 (return): +5.3 cfs (6% of that reach's correction)
ISOM SPRING NO4 (return): +5.3 cfs (6% of that reach's correction)
ISOM SPRING NO5 (return): +5.3 cfs (6% of that reach's correction)
ISOM SPRING NO6 (return): +5.3 cfs (6% of that reach's correction)
ISOM SPRING & PIPELINE NO8 (return): +5.3 cfs (6% of that reach's correction)
ISOM POND NO2 (diversion): +5.3 cfs (6% of that reach's correction)
ISOM POND NO3 (diversion): +5.3 cfs (6% of that reach's correction)
ISOM POND NO5 (diversion): +5.3 cfs (6% of that reach's correction)

Data provenance & quality

Where these numbers come from and how far they can be trusted. Grade C (3/6 points) — the components below are the finding; the letter alone is not. Sources: DWR HydroBase snapshot HydroBase_CO_20260707 (imported 2026-08-19) for history, plus the CDSS REST API for current conditions.

Check	State	What was measured
gage freshness	stale	newest gage reading is 55 day(s) old (target 7)
diversion record	expected-lag	newest diversion record is 304 day(s) old (DWR publishes ~1 year in arrears)
structure coverage	sparse	6% of schematic structures have data

Independent check: PASS — 100.0000% agreement across 291,280 stored values re-checked against DWR's authoritative record (HydroBase_CO_20260707), over 20 structures. 0 disagreement(s) beyond a 0.01 cfs tolerance. Checked 2026-08-19; a rotating sample covers the whole basin across successive runs, and the structures this report cites are checked every time.

Federal cross-check: PASS — 97.48% day-level agreement with USGS's own published records for the same gages, across 2 co-listed station(s) and 36,337 overlapping days (within max(2%, 0.5 cfs) daily). Pre-1950 records at some gages carry known between-agency day-stamp and transcription differences — scored at each year's best ±1-day alignment; residual disagreement is real historical divergence, flagged for review.

30 gage(s) / 135,072 daily values (1938-10-01–2026-07-06); 133 structure(s) with diversion records; 1104 with decreed rights. Methodology has not yet had independent expert review — treat every figure as an advisory screen, not an administrative or legal conclusion.

8,080 water-level measurements across 76 monitored well(s) — 64 alluvial, 0 bedrock — plus 0 administered well(s) reporting metered pumping.

What is being counted

Observation wells and pumping wells are different populations and are never conflated: water levels come from monitored observation wells, and metered pumping comes from administered wells reporting through diversion records. Click any well to chart its own record.

Well map

3D aquifer x-ray

Every aquifer unit as its own head surface, animated through time.

How the surfaces are built, and what they are not

Alluvial water table on top, Denver Basin members (Dawson, Denver, Arapahoe, Laramie–Fox Hills) stacked beneath where measured, interpolated from measured water levels. Units are never mixed; a surface exists only inside its own unit's well coverage, with no extrapolation; thin epochs are suppressed and say why. Vertical scale is exaggerated for readability and z is head elevation in feet. These are measured heads, not a calibrated groundwater model.

Water-table trends

Of 28 well(s) with enough record for a trend test: 6 declining, 2 rising.

Fastest-declining wells	Setting	ft / decade	Span	p
▸ LGRB-Poly 30	alluvial	-2.87	10 yr	0.0491
▸ NC04900936BA LGRB Poly 28	alluvial	-2.79	11 yr	0.0051
▸ LGRB-Poly 23	alluvial	-2.74	10 yr	0.0042
▸ NC05101035BD LGRB Poly 8	alluvial	-2.64	12 yr	0.0236
▸ LGRB-Poly 19	alluvial	-2.1	10 yr	0.02
▸ LGRB-Poly 6	alluvial	-1.44	10 yr	0.0491

Stream corridors — the surface connection

Where a reach's gain or loss has shifted, the wells within two miles of its anchoring gage and what their water table did over the same era.

How the corridor is assembled

For each reach whose gain/loss has shifted (Trends tab): the wells within 2 miles of its anchoring gage, their pooled water-table history over the same era, and an advisory Glover screen of lagged stream depletion from nearby metered pumping. v1 proximity = distance to the reach's anchoring gage; segment-based reach join is a flagged upgrade.

FAIRVIEW INLET OFF THE SOUTH CANAL NEAR MONTROSE: 1 alluvial well(s) nearby; pooled water table -0.5 ft (2014–2024, decreasing, p=0.0491)

GARNET DITCH: 3 alluvial well(s) nearby; pooled water table -0.3 ft (2014–2024, no_trend, p=0.5915)

IRONSTONE CANAL NEAR OLATHE, CO: 3 alluvial well(s) nearby; pooled water table +1.2 ft (1976–2024, no_trend, p=0.0584)

Wells labeled by administrative world before anything else is said about them: tributary alluvium participates in the priority system; designated-basin and Denver Basin bedrock aquifers are governed differently and are excluded from stream-connection reasoning. Read bedrock declines differently too: deep bedrock aquifers recharge negligibly on human timescales, so a falling bedrock level is storage mining — effectively permanent — not a drought response that a wet year undoes. All screens advisory.

3 reservoir(s) with 58 storage measurement(s), 1950–2022.

Why storage matters to the flow network

Storage change is real water the mass balance must credit — a losing reach beside a filling reservoir isn't losing water, it's banking it.

Reservoir map — how full is each vessel?

What “full” is measured against

Bubble size is proportional to a reservoir's record-high storage. Fill is its last recorded storage as a share of its surveyed capacity (USACE National Inventory of Dams) where a confident NID match exists — the tooltip names the matched dam — and as a share of its own record high otherwise. A wrong capacity would be worse than an honest record high, so only confident joins upgrade.

A dashed teal ring marks reservoirs reporting live DWR telemetry: their fill reflects yesterday's storage, is drawn as a dotted tail on charts, and is treated as provisional until the next verified HydroBase snapshot supersedes it.

A dashed red ring marks a dam under an active storage restriction from DWR's Dam Safety branch — the State Engineer has limited how much it may legally store, so a low fill can be an order, not a drought. Hazard class and inspection condition come from the same record, joined only where the dam carries this reservoir's WDID or a confident NID match — a wrong dam's restriction would be worse than none shown.

Basin storage, end of each water year

End-of-water-year totals; per-year reservoir counts shown because reporting coverage varies -- a total is only comparable to years with similar counts.

Largest reservoirs on record

Click a row to chart its full storage history, or open its dossier for rights, documents and dam-safety facts.

Reservoir	Last recorded storage (AF)	As of	Full	Dam (DWR Dam Safety)
▸ CITIZENS RESERVOIR (4103651)	123	1956-09-01	—	—	dossier →
▸ MOCK RESERVOIR NO 1 (4103653)	40	1952-05-01	—	—	dossier →
▸ BUCKHORN RESERVOIR #2 (4103650)	0	2022-09-02	—	—	dossier →

Right now

This is the 4th-driest week 27 in 88 years of record at UNCOMPAHGRE RIVER AT DELTA, CO. (as of 2026-06-29; this week’s flow sits at the 5th percentile for the date). On this week’s US Drought Monitor, Delta County is 35% in D3 extreme drought (2026-09-01). The law agrees: the most senior active call leaves 87% of this district’s decreed flow rights junior to the calling right this week.

Every year since 1938, week by week

Each thin row is a year at UNCOMPAHGRE RIVER AT DELTA, CO.; each cell is one week’s flow ranked against the same calendar week of every other year — warm means dry for the date, blue wet, so seasonality cancels and droughts appear as warm bands. Gaps are missing record, never a dry river. Click a year to reconstruct it on the Historical tab.

The Drought Monitor’s view since 2000

Mean share of area in each class across Delta, Montrose counties — the counties this district’s gages sit in, which overlap the district imperfectly. The Drought Monitor weighs soils, vegetation and local reports; it is CONTEXT beside the river’s own record above, not the water-rights picture.

The law’s own drought gauge

When water runs short, administration answers: calls reach further back in time, and more decreed rights go junior to the calling right. This is that response, weekly since 2002 — the share of this district’s decreed flow rights junior to the most senior active call. Watch it spike in the named droughts below, and linger after the river recovers.

Computed from DWR’s call record (62 calls touching this district) against the district’s rights index. Scoping is deliberately coarse — a call’s own district, or districts named in its comments — and this is administration’s RESPONSE, not a per-structure verdict (each dossier’s curtailment card does that, with stream miles). A deepening call can also reflect growing demand, not only shrinking supply.

This basin’s droughts, by its own record

Drought	Span	Weeks	Trough percentile	Recovery
the 2018 drought	2018-08-06 → 2019-02-04	26	15th (2018-10-01)	3 weeks
the 2012-13 drought	2013-06-03 → 2013-11-25	25	19th (2013-07-22)	0 weeks
the 2012-13 drought	2012-07-30 → 2013-02-11	28	15th (2012-10-08)	40 weeks
the 2002 drought	2003-06-23 → 2004-01-12	29	16th (2003-08-25)	1 week
the 2002 drought	2002-07-01 → 2003-03-10	36	6th (2002-09-23)	45 weeks
unnamed dry spell	1988-08-22 → 1990-09-17	108	14th (1990-04-23)	67 weeks
the 1981 drought	1980-12-08 → 1981-09-14	40	20th (1981-02-23)	12 weeks
the 1977 drought	1977-04-04 → 1978-06-19	63	12th (1977-10-31)	43 weeks
unnamed dry spell	1966-10-17 → 1967-09-11	47	18th (1966-11-28)	42 weeks
the 1963-64 drought	1963-05-13 → 1963-12-30	33	21st (1963-08-12)	32 weeks
unnamed dry spell	1959-05-11 → 1959-11-30	29	24th (1959-07-27)	95 weeks
the 1950s drought	1955-09-12 → 1957-04-15	83	12th (1956-12-03)	5 weeks
the 1950s drought	1954-05-10 → 1954-12-20	32	14th (1954-07-05)	126 weeks
the 1950s drought	1950-10-09 → 1952-06-09	87	12th (1951-05-21)	10 weeks

Detected mechanically: the 26-week smoothed percentile below the 30th for at least 20 weeks; recovered on regaining the 50th. The knobs are stated because the episode list depends on them — a different reasonable choice merges or splits episodes at the edges. Names are attached where an episode overlaps a drought Colorado already talks about.

What drought has cost here

Since 2011, federal crop insurance has paid $8,457 in drought-caused claims across Delta, Montrose counties — 0.0% of all insured crop losses there. The worst year was 2018 ($5,315).

USDA crop-insurance indemnities where the recorded cause of loss is drought, summed over the counties this district's gages sit in. Counties overlap water districts imperfectly, and insured-crop claims are a floor on drought damage, not a total. Source: USDA RMA cause-of-loss files.

When this basin claimed its water

Every bar is a year’s new appropriations (826 rights across 89 years of shared record), colored by that year’s wetness from the barcode above. Here the correlation is -0.03 — essentially no wet-dry pattern; here, law and settlement set the pace, not the weather. Across the state both behaviors exist: ephemeral southwest basins file after wet demonstrations, transbasin-source basins under drought — and the biggest statewide filing waves sat in the 1950s drought and after 2002, not in the wet 1980s–90s.

Appropriation dates are the CLAIMED initiation of a right, not the courthouse filing date; the record is survivor-biased (abandoned claims are absent, so failed dry-era scrambles are undercounted); and the big 1960s and 2000s spikes sit on legal events — the pre-1969-Act adjudication era and 2000s legislation — not on weather. A correlation here is a description, never a cause.

New to how a dry winter becomes a call on the river? Anatomy of a drought walks the chain in four minutes — snow to rivers to reservoirs to calls to the water table.

Decreed rights on this network run from 1877-05-01 to 2025-03-06. Of the 20 structures with a yield estimate, the median one’s senior right was in priority 54% of a median irrigation season and 0% in a dry one. 25 abandonment screens and 84 compliance flags are listed below as leads for review — a screen is not an abandonment and a flag is not a violation.

Rights on file: 1249 across 1104 structure(s); 161 structure(s) carry 0 court-case references. Advisory reading aids on public DWR data — not administrative or legal conclusions.

Is the river getting harder to divert from?

Over 2003–2025, administration on this district has been tightening: 1 of 3 measures (days under call, calls set, seniority of the controlling call) are moving toward more administration, none the other way.

The three measures, year by year

One row per whole calendar year inside the call record's coverage (23 years); partly-covered years are omitted rather than reported as quiet. Trend is Mann-Kendall with the same significance gate as every other trend on this site. Counted from DWR's published call record, which begins in the early 2000s: earlier years are absent, not quiet. A rise in the number of calls set can also reflect how finely an administrator records one episode, which is why days under call -- insensitive to that -- is the component to read first. Advisory summary of the public record, not an administrative finding.

Year	Days under call	Calls set	Controlling priority (median)
2014	0	0	—
2015	277	127	1885-08-11
2016	366	108	1890-11-17
2017	319	94	1888-01-23
2018	291	160	1882-06-01
2019	319	93	1888-01-25
2020	246	141	1881-12-17
2021	275	103	1883-05-05
2022	365	93	1884-11-01
2023	277	59	1898-10-15
2024	275	56	1883-06-01
2025	365	100	1884-11-01

Why diversions stopped — call-based explanations

Sustained diversion stops matched to senior administrative calls.

BUCKHORN DITCH (4100509) DWR↗ stopped 2025-08-13 (40+ days) — call at MOODY DITCH curtailing 100% of its decreed rate [heuristic-strong]
FREEMAN DITCH (4100525) DWR↗ stopped 2025-07-20 (14+ days) — call at MINNESOTA CANAL curtailing 100% of its decreed rate [heuristic-strong]
J H ANDERSON D NO 1 (4100535) DWR↗ stopped 2025-07-20 (79+ days) — call at MINNESOTA CANAL curtailing 100% of its decreed rate [heuristic-strong]
CEDAR PARK DITCH (4100512) DWR↗ stopped 2025-06-22 (31+ days) — call at MAVERICK DRAW DITCH curtailing 100% of its decreed rate [heuristic-strong]
GLENDENING DITCH (4100529) DWR↗ stopped 2025-06-08 (14+ days) — call at MIDKIFF & ARNOLD D curtailing 100% of its decreed rate [heuristic-strong]
CHAPARRAL D NO 2 (4100513) DWR↗ stopped 2025-05-26 (43+ days) — call at TERROR DITCH curtailing 100% of its decreed rate [heuristic-strong]
CHAPARRAL D NO 2 (4100513) DWR↗ stopped 2025-04-29 (12+ days) — call at SANDSTONE BLUFF DITCH curtailing 100% of its decreed rate [heuristic-strong]
J. C. FREES PRIVATE DITCH (4100526) DWR↗ stopped 2025-04-01 (28+ days) — call at ROBERTS STUCKER DITCH curtailing 100% of its decreed rate [heuristic-strong]
OURAY DITCH (4100549) DWR↗ stopped 2024-10-31 (185+ days) — call at TRANSFER DITCH curtailing 64% of its decreed rate [heuristic-partial]
FANSHER HORSEFLY NO 2 D (4100522) DWR↗ stopped 2024-10-30 (181+ days) — call at TRANSFER DITCH curtailing 100% of its decreed rate [heuristic-strong]
FREEMAN DITCH (4100525) DWR↗ stopped 2024-10-29 (182+ days) — call at TRANSFER DITCH curtailing 50% of its decreed rate [heuristic-partial]
GLENDENING DITCH (4100529) DWR↗ stopped 2024-10-27 (177+ days) — call at TRANSFER DITCH curtailing 57% of its decreed rate [heuristic-partial]

Right yield — how often could these rights actually divert?

Share of irrigation-season days each structure's rights were not called out, derived from the 22-year district-scoped call record (senior right = floor, junior right = ceiling constraint). Call-record-derived; DWR's own analysis governs where available.

Structure	Senior priority	Senior right: median / dry yr	Junior right: median / dry yr
MONTROSE & DELTA CANAL (4100545) DWR↗	1881-11-01	71.3% / 10.7%	10.7% / 0.0%
IRONSTONE CANAL (4100534) DWR↗	1882-01-05	53.8% / 0.0%	10.7% / 0.0%
DRY CREEK FEEDER D (4100610) DWR↗	1887-02-28	10.7% / 0.0%	10.7% / 0.0%
SELIG CANAL (4100559) DWR↗	1882-01-27	53.8% / 0.0%	10.7% / 0.0%
GARNET DITCH (4100527) DWR↗	1883-06-18	31.3% / 0.0%	10.7% / 0.0%
UNCOMPAHGRE (LOUTSENHIZE (4101233) DWR↗	1882-02-23	53.8% / 0.0%	10.7% / 0.0%
SPRING CREEK VALLEY D (4100564) DWR↗	1883-06-13	31.3% / 0.0%	31.3% / 0.0%
IRONSTONE EXTENSION D (4100983) DWR↗	1885-02-28	10.7% / 0.0%	10.7% / 0.0%
EAST CANAL (4100520) DWR↗	1882-05-01	53.8% / 0.0%	10.7% / 0.0%
LOUTSENHIZER CANAL (4100537) DWR↗	1881-11-01	71.3% / 10.7%	10.7% / 0.0%
PURDY AND VICKERS DITCH (4100517) DWR↗	1882-03-02	53.8% / 0.0%	0.0% / 0.0%
HAIRPIN LTL D (4100532) DWR↗	1911-09-02	5.3% / 0.0%	5.3% / 0.0%

Abandonment radar (25 screens)

Absolute rights with 10+ years of no recorded diversions. Screens only — storage, alternate points, and plan operations can explain nonuse lawfully. And diversion REPORTING itself only reached its modern level ~1950 — idleness that begins before then may be unreported use, not nonuse (flagged † below).

E E FRASIER SPGS & SEPG (4100616) DWR↗ (1887-06-01, 1.5 cfs decreed): last active 1950 — 75 years idle
SPRING CREEK NO1 PL (4100711) DWR↗ (1976-09-07, 0.1 cfs decreed): last active 1954 — 71 years idle
SWEITZER DITCH (4100714) DWR↗ (1911-09-02, 1.0 cfs decreed): last active 1954 — 71 years idle
MONTROSE CITY DITCH (4100683) DWR↗ (1884-04-05, 10.0 cfs decreed): last active 1955 — 70 years idle
EAST FORK FDR PIPELINE (4100625) DWR↗ (1933-10-25, 1.0 cfs decreed): last active 1956 — 69 years idle
LABARR DITCH NO1 (4100664) DWR↗ (1976-04-29, 1.8 cfs decreed): last active 1969 — 56 years idle
CHAPARRAL DITCH (4100603) DWR↗ (1911-09-02, 0.4 cfs decreed): last active 1974 — 51 years idle
MENKE NORTH DITCH ENLT (4100686) DWR↗ (1947-03-01, 1.0 cfs decreed): last active 1974 — 51 years idle
CITIZENS RESERVOIR (4103651) DWR↗ (1912-09-01, 0.0 cfs decreed): last active 1974 — 51 years idle
MOCK RESERVOIR NO 1 (4103653) DWR↗ (1911-09-02, 0.0 cfs decreed): last active 1974 — 51 years idle

Compliance screens (84 advisory flags)

Screened 112 of 1104 structures with rights (118 have diversion history on file). A flag is a lead for expert review — augmentation plans, exchanges, and free-river conditions can make over-decree diversions lawful and are deliberately not modeled.

IRONSTONE CANAL (4100534) DWR↗: Observed p99 daily rate 456.0 cfs (max 578.0) exceeds total decreed absolute 202.7 cfs across 48877 recorded day(s).
SELIG CANAL (4100559) DWR↗: Observed p99 daily rate 260.0 cfs (max 377.0) exceeds total decreed absolute 121.9 cfs across 51459 recorded day(s).
EAST CANAL (4100520) DWR↗: Observed p99 daily rate 189.0 cfs (max 1530.0) exceeds total decreed absolute 60.4 cfs across 45736 recorded day(s).
LOUTSENHIZER CANAL (4100537) DWR↗: Observed p99 daily rate 188.0 cfs (max 741.0) exceeds total decreed absolute 46.4 cfs across 46945 recorded day(s).
IRONSTONE EXTENSION D (4100983) DWR↗: Observed p99 daily rate 166.0 cfs (max 192.0) exceeds total decreed absolute 61.2 cfs across 2128 recorded day(s).
UNCOMPAHGRE CEDAR CR D (4100571) DWR↗: Observed p99 daily rate 44.1 cfs (max 58.0) exceeds total decreed absolute 29.1 cfs across 9853 recorded day(s).
F. J. LATERAL (4100631) DWR↗: Observed p99 daily rate 36.8 cfs (max 39.5) exceeds total decreed absolute 15.0 cfs across 2078 recorded day(s).
ROSS BROS DITCH (4100554) DWR↗: Observed p99 daily rate 34.9 cfs (max 38.3) exceeds total decreed absolute 22.2 cfs across 26028 recorded day(s).
STARK VOLKMAN DITCH (4100566) DWR↗: Observed p99 daily rate 30.3 cfs (max 55.3) exceeds total decreed absolute 20.1 cfs across 32500 recorded day(s).
CHIPETA BEAUDRY DITCH (4100515) DWR↗: Observed p99 daily rate 23.6 cfs (max 32.0) exceeds total decreed absolute 20.8 cfs across 28093 recorded day(s).

Seniority (top structures by decreed rate)

Structure	Senior priority date	Rights	Decreed abs (cfs)	Conditional?
MONTROSE & DELTA CANAL (4100545) DWR↗	1881-11-01	11	627.1	—
IRONSTONE CANAL (4100534) DWR↗	1882-01-05	7	202.7	—
DRY CREEK FEEDER D (4100610) DWR↗	1887-02-28	1	180.0	—
SELIG CANAL (4100559) DWR↗	1882-01-27	6	121.9	—
GARNET DITCH (4100527) DWR↗	1883-06-18	2	93.3	—
UNCOMPAHGRE (LOUTSENHIZE (4101233) DWR↗	1882-02-23	3	81.6	—
SPRING CREEK VALLEY D (4100564) DWR↗	1883-06-13	1	65.1	—
IRONSTONE EXTENSION D (4100983) DWR↗	1885-02-28	1	61.2	—
EAST CANAL (4100520) DWR↗	1882-05-01	4	60.4	—
LOUTSENHIZER CANAL (4100537) DWR↗	1881-11-01	4	46.4	—
PURDY AND VICKERS DITCH (4100517) DWR↗	1882-03-02	5	46.2	—
HAIRPIN LTL D (4100532) DWR↗	1911-09-02	1	45.0	—
SATISFACTION DITCH (4100558) DWR↗	1882-01-27	3	36.0	—
OURAY DITCH (4100549) DWR↗	1877-05-01	10	36.0	—
BALDY DITCH (4100501) DWR↗	1884-06-20	1	30.0	—

No inventory or legal-document changes detected since the daily watch began.

Water-court filings this month (division-wide)

15 applications in the 2026-08 resume for this basin's division — new rights, changes, augmentation plans — from the water clerk's statutory monthly notice (C.R.S. 37-92-302), the earliest public signal of a new claim. Filings are division-wide, not district-filtered: check the county column. Full resume PDF at the Judicial Branch →

Anyone affected may file a statement of opposition until 2026-10-31 (56 days left). C.R.S. 37-92-302(3): due by the last day of the second month following the filing month — computed, not legal advice; confirm with the water clerk.

All 15 filings, with excerpts

Case	What it asks	County	Excerpt
`09CW89`	reasonable diligence, make absolute	SAN MIGUEL	09CW89, 96CW313, 08CW186) - SAN MIGUEL COUNTY, SAN MIGUEL RIVER AND ITS TRIBUTARIES - APPLICATION FOR FINDINGS OF REASONABLE DILIGENCE AND TO MAKE ABSOLUTE IN PART Town of Telluride, c/o Jennifer M. DiLalla, Molly K. Haug-Rengers, Moses, Wittemyer, Harrison an…
`26CW19`	reasonable diligence	—	Case No. 26CW19 (Ref No. 06CW107, 13CW093, 20CW017) Applicant Ed and Ruth Kneese 13890 Marine Road Montrose, CO 81403. Application and Amended Application for Finding of Reasonable Diligence. Kneese Wastewater Ditch SE1/4 SE1/4 Section 20 T49N R9W NMPM. Eastin…
`26CW20`	make absolute	—	Case No. 26CW20 (Ref No. 99CW199, 06CW10, 13CW90, 20CW26) Applicant David and Elizabeth Koos 15464 2525 Road Cedaredge CO 81413. Application to Make Absolute. Koos Well - NE1/4NW1/4SW1/4 Section 34 T13S R94W 6th. Easting 0248977 Northing 4307260. Source: Groun…
`26CW21` 4301123	new surface right	—	Case No. 26CW21 Applicant Daniel Lee Bolton 34879 Powell Mesa Road Hotchkiss CO 81419. Application for Absolute Surface Water Rights. Papa’s Spring – NW1/4 NW1/4 Section 20 T14S R92W 6th. Easting 265356 Northing 4301123. Source: Spring Tributary of the North F…
`26CW22`	reasonable diligence	—	Case No. 26CW22 (Ref No. 14CW3000, 20CW0024) Applicant Daniel Lee Bolton 34879 Powell Mesa Road Hotchkiss CO 81419. Application for Finding of Reasonable Diligence. Well Permit #228338A – NW1/4 NW1/4 Section 20 T14S R92W 6th. Source: Ground Water Tributary of …
`26CW3038` 4315025	reasonable diligence	GUNNISON	Case No. 26CW3038 (Ref No. 13CW62, 20CW3012) Gunnison County – North Fork Gunnison River. Applicant: Thomas M. Abbott and Abbott Ranches, LLC, c/o Bradley N. Switzer, P.O. Box 816, Montrose, CO 81402, (970) 249-8749; APPLICATION FOR FINDING OF REASONABLE DILIG…
`26CW3039`	reasonable diligence, make absolute	SAN MIGUEL	Case No. 26CW3039 (Ref No. 19CW3082) San Miguel County – San Miguel River; San Juan Vista Landowners Association; c/o William T. Raley and John R. Pierce, DUFFORD WALDECK, 744 Horizon Court, Suite 300, Grand Junction, CO 81506, (970) 248-5865; APPLICATION TO M…
`26CW3040` 5905273	reasonable diligence, make absolute	—	Case No. 26CW3040 (Ref No. 94CW60, 13CW3057, 20CW3014) APPLICATION TO MAKE CONDITIONAL RIGHTS ABSOLUTE IN PART AND FOR FINDING OF REASONABLE DILIGENCE. Applicant: Silver Sage Property Owners’ Association, Inc., c/o H&H CPA's & Advisors, P.O. Box 1218, Crested …
`26CW3041` 5903781	reasonable diligence	IN GUNNISON	Case No. 26CW3041 (Ref No. 81CW306, 20CW3029) IN GUNNISON COUNTY - APPLICATION FOR FINDING OF REASONABLE DILIGENCE City of Gunnison, a Colorado Municipal Corporation c/o Jennifer M. DiLalla, Cameron J. Abatti, Moses, Wittemyer, Harrison and Woodruff, P.C., 259…
`26CW3042`	make absolute	—	Case No. 26CW3042 (Ref No. 20CW3) 1. Applicant: MambaOn3 Real Estate LLC (“Applicant”), 9249 South Broadway, Ste. 200-824, Highlands Ranch, CO 80129, nerissa@mambaon3.com, (424) 303-3880. Direct all pleadings and correspondence to Applicant’s attorneys: Ramsey…
`26CW3043`	reasonable diligence	SAN MIGUEL	Case No. 26CW3043 (Ref No. 13CW79, 20CW3025) SAN MIGUEL COUNTY. Application for Finding of Reasonable Diligence. Telluride Pines Homeowners Association, P.O. Box 1071, Telluride, CO 81430 (970) 394-4480; c/o Peter D. Jaacks and April D. Hendricks, Jewell Jimme…
`26CW3044`	reasonable diligence, make absolute	DELTA	Case No. 26CW3044 (Ref No. 13CW3021, 20CW3009) DELTA COUNTY. Applicant: Harris and Sons Stirrup Bar Ranch, LLC, c/o Doug Harris, Manager, P.O. Box 940, Paonia, CO 81428 (David J. Skarka, Camp & Skarka, LLC, 415 Palmer St., Delta, CO 81416; 970-874-9777). APPLI…
`26CW3045`	—	—	Case No. 26CW3045 (Ref No. 19CW3003, W-3280, 96CW132, 09CW142, 92CW176,…
`26CW3046`	reasonable diligence	GUNNISON	Case No. 26CW3046 (Ref No. 89CW219, 97CW133, 04CW050, 11CW78,18CW3013). GUNNISON COUNTY Application for Findings of Reasonable Diligence and to Make Certain Conditional Water Rights Partially Absolute. Applicant: Trappers Crossing at Crested Butte Association,…
`96CW177`	—	—	Case No. 96CW177; Depth: Original decree is for 82 separate wells of unspecified depth; Outline of what has been done toward completion of the appropriation and application of water to a beneficial use: Applicant was granted, by Decree in Case No. W-2264 (ref …

Active substitute water supply plans in this district

Temporary State Engineer approvals to divert out of priority (37-92-308 / 37-90-137). A structure operating under one behaves differently under a call than its decreed rights alone suggest — the priority tables above don't know about these; this list does. Source: DWR’s active-SWSP register, refreshed nightly.

Plan	Type	Status	Expires	Structure	Documents
COLONA PIT M-94-005	37-90-137(11) GRAVEL PIT PLAN	Approved	—	—	plan file

If a call were placed at a given seniority, which structures in this basin would be out of priority, and how much of their decreed rate would be curtailed? Computed from this basin's cached decrees.

What this does and doesn't model. Seniority arithmetic only: every right junior to the call is treated as curtailed. It does not model reach applicability — structures downstream of the calling point are not administered by it — and it applies no futile-call judgment. Read it as “who is junior to this date, and by how much,” not as a prediction of what the Division Engineer would actually order.

Pick a calling right

Real decrees from this basin, ordered by administration number — that is, by actual seniority. The years will look out of order, and that is correct: an administration number encodes the adjudication date as well as the appropriation date, so a right appropriated in 1970 can be administered ahead of one from 1950. A senior call curtails almost everything; a junior one curtails almost nothing.

Or enter an administration number directly

Administration number

DWR administration numbers encode appropriation and adjudication dates; lower is more senior.

Topology cross-check: 4 parent disagreements (vs DWR's route framework — under review)

This flow network was built mechanically; DWR's Source Water Route Framework disagrees with it in the places below. Each row is a question a human reviewer has not yet answered — not an error verdict. Checked 16 streams, 12 agree. Know this water? Tell us →

Stream	This site routes it to	DWR routes it to
Coal Creek	the mainstem	Dry Creek
Montrose Arroyo	the mainstem	Cedar Creek
Dolores Creek	the mainstem	Happy Canyon Creek
Hairpin Creek	the mainstem	Cedar Creek

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