McElmo Creek Basin

Division 7 · Water District 32

Auto-mapped

McElmo Creek Basin on the ground — the ditches, wells, reservoirs and gages of Water District 32 · 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.

4% of normal flow, week of 2026-06-29

17 calls active on it right now

The Mcelmo Creek is critically low for late June -- 4% of normal flow, its 3rd-driest such week in 76 years of record. 17 calls stand against it right now; the most senior right calling dates to 1876.

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 7 ranked gages are running at a median 43% of their own long-term norm for this window — 7 below a typical year, 0 at or above. Driest relative to its record: MCELMO CREEK NEAR COLORADO-UTAH STATE LINE, ranking 1st lowest of 76 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 21:18 from 16 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 16 gages with enough record, 4 are trending down and 0 up, and 6 carry a detected shift. The clearest is U Lateral Canal below Great Cut Dike near Dolores, its annual mean flow changing -3.82 cfs per decade (-12.6% of its median annual flow) over 29 years (p<0.0001). The other 10 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
▸ U Lateral Canal below Great Cut Dike near Dolores UCANALCO	↓ decreasing	-3.82 cfs -12.6%	p<0.001	29	~2012
▸ McElmo Creek above Trail Canyon near Cortez MCELMZCO	↓ decreasing	-13.62 cfs -29.1%	p<0.001	32	~2011
▸ ⚠️ Rocky Ford Canal #2 above Totten Reservoir near Cortez RF2ATOCO	↓ decreasing	-0.57 cfs	p=0.001	24	~2011
▸ Mud Creek at State Highway 32, near Cortez MUDHIGCO	↓ decreasing	-0.58 cfs -8.5%	p=0.002	36	~2017
▸ Lone Pine Canal below Great Cut Dike near Dolores MVIDIVCO	no clear trend	-3.14 cfs -4.7%	p=0.217	32	~2013
▸ McElmo Creek near Colorado-Utah State Line MCELMSCO	no clear trend	-1.10 cfs -2.4%	p=0.615	75	~2011

⚠️ 1 gage flagged: their records may have quietly shifted against their neighbours, so treat their trends with caution.

How drift is detected

Every gage's annual flows are compared against each neighbour's as a double-mass curve (Searcy & Hardison, USGS WSP 1541-B); a Pettitt step test looks for a break in the ratio. A gage is flagged only when the breaks AGREE across its references, and a break against an already-suspect gage is never counted against a healthy one. A double-mass break means the ratio between two gages changed, not that either gage is faulty: a new diversion, a reservoir, or an import changes that ratio exactly as a rating shift does. Screening aid for expert review, never a measurement verdict.

10 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. 10 gage(s) and 182 structure(s) report in 2026, but structure reporting only reached half its modern level around ~1980. 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)
1920s	1	0
1940s	1	0
1950s	1	1
1960s	1	52
1970s	3	126
1980s	6	169
1990s	6	186
2000s	8	233
2010s	10	200
2020s	10	184

Mass-balance (network closure) trend

Structure divrec-history backfill coverage as of the last check: 58% of 398 schematic-relevant structures. Kink count trend: no_trend (p=0.115), kink magnitude trend: no_trend (p=0.119) across 45 qualifying year(s).

Reach gain/loss shifts (1985–2026)

Mass-balance kinks computed for every summer month back to 1985 (148 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.

ROCKY FORD CANAL #2 ABOVE TOTTEN RESERVOIR NEAR CORTEZ: reach shifted from -243 cfs to -89 cfs summer mean (more gaining, p=0.043, 24 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=-0.63) -- part of it may be unaccounted water becoming accounted, not hydrologic change]

Groundwater now has its own tab: 22 monitored well(s), water-table trends, stream corridors, and the advisory depletion screen.

Reservoirs now has its own tab: 15 reservoir(s), end-of-year storage back to 1975, click-to-chart histories.

Cross-gage pattern fingerprint

Not enough gages with a long enough common-coverage window yet to fingerprint shared patterns.

Data provenance & quality

Where these numbers come from and how far they can be trusted. Grade B (4/6 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	partial	58% of schematic structures have data

Independent check: PASS — 100.0000% agreement across 184,831 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 — 99.85% day-level agreement with USGS's own published records for the same gages, across 8 co-listed station(s) and 75,162 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.

16 gage(s) / 141,397 daily values (1926-10-01–2026-07-06); 357 structure(s) with diversion records; 638 with decreed rights. Methodology has not yet had independent expert review — treat every figure as an advisory screen, not an administrative or legal conclusion.

96 water-level measurements across 22 monitored well(s) — 7 alluvial, 0 bedrock — plus 1 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 0 well(s) with enough record for a trend test: 0 declining, 0 rising.

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.

15 reservoir(s) with 8,715 storage measurement(s), 1975–2026. Basin storage as of 2025-10-31 (the record's own end — reservoir records publish ~annually): 3,647 AF across 3 reservoir(s).

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)
▸ TOTTEN RESERVOIR (3203601)	2,135	2025-10-31	—	—	dossier →
▸ A M PUETT RES OUTLET (3200704)	978	2009-10-16	—	—	dossier →
▸ A M PUETT RESERVOIR (3203603)	770	2025-10-31	—	—	dossier →
▸ NARRAGUINNEP RESERVOIR (3203602)	742	2025-10-31	—	—	dossier →
▸ MARINE LIFE RESORT RESERVOIR (3203794)	35	2017-10-31	—	—	dossier →
▸ WILKERSON POND NO 1 (3203604)	11	2011-10-31	—	—	dossier →
▸ BUTTS RESERVOIR (3203605)	9	2011-10-31	—	—	dossier →
▸ LIVELY RESERVOIR (3203597)	5	2011-10-31	—	—	dossier →

Right now

This is the 3rd-driest week 27 in 76 years of record at MCELMO CREEK NEAR COLORADO-UTAH STATE LINE (as of 2026-06-29; this week’s flow sits at the 4th percentile for the date). On this week’s US Drought Monitor, Montezuma County is 54% in D3 extreme drought (2026-09-01). The law agrees: the most senior active call leaves 76% of this district’s decreed flow rights junior to the calling right this week.

Every year since 1951, week by week

Each thin row is a year at MCELMO CREEK NEAR COLORADO-UTAH STATE LINE; 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 Montezuma, Montezuma 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 2013 — 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 (195 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
unnamed dry spell	2025-03-17 → 2026-07-06	68	6th (2026-07-06)	not yet
unnamed dry spell	2023-12-18 → 2024-12-23	53	16th (2024-08-05)	not yet
the 2020-22 drought	2020-04-13 → 2023-04-17	157	5th (2022-06-20)	3 weeks
the 2018 drought	2018-03-05 → 2019-06-24	68	5th (2019-01-28)	202 weeks
the 2012-13 drought	2014-03-03 → 2014-11-24	38	12th (2014-06-23)	48 weeks
the 2012-13 drought	2013-01-14 → 2013-11-11	43	20th (2013-07-29)	102 weeks
the 2012-13 drought	2012-04-23 → 2012-11-05	28	23rd (2012-07-02)	155 weeks
the 2002 drought	2002-04-01 → 2004-11-01	135	7th (2002-08-19)	2 weeks
the 1977 drought	1977-04-04 → 1978-06-12	62	7th (1978-01-16)	6 weeks
the 1963-64 drought	1963-11-11 → 1964-06-08	30	17th (1964-03-02)	28 weeks
unnamed dry spell	1960-11-21 → 1961-05-22	26	16th (1961-01-09)	6 weeks
unnamed dry spell	1959-07-13 → 1960-05-16	44	18th (1959-09-21)	2 weeks
the 1950s drought	1956-10-22 → 1957-05-27	31	6th (1956-12-31)	0 weeks
the 1950s drought	1954-11-01 → 1955-03-28	21	21st (1954-11-29)	6 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 1991, federal crop insurance has paid $1,489,504 in drought-caused claims across Montezuma county — 11.1% of all insured crop losses there. The worst year was 2021 ($338,603).

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 (356 rights across 76 years of shared record), colored by that year’s wetness from the barcode above. Here the correlation is +0.45 — this basin tended to claim water after wet years, when the supply had just shown itself. 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 1868-03-02 to 2022-08-05. Of the 20 structures with a yield estimate, the median one’s senior right was in priority 16% of a median irrigation season and 1% in a dry one. 25 abandonment screens and 145 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: 687 across 638 structure(s); 65 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	319	117	1883-05-15
2015	316	90	1899-05-13
2016	273	94	1888-02-08
2017	297	98	1904-01-02
2018	285	164	1878-05-15
2019	186	53	1880-06-01
2020	240	171	1986-11-23
2021	246	143	1876-11-01
2022	261	161	1888-03-20
2023	198	82	1880-06-01
2024	231	114	1876-10-10
2025	281	169	1888-03-20

Why diversions stopped — call-based explanations

Sustained diversion stops matched to senior administrative calls.

BORD DITCH (3200512) DWR↗ stopped 2025-10-14 (10+ days) — call at LA PLATA RIVER BASIN curtailing 100% of its decreed rate [heuristic-strong]
CHARLES MATTSON DITCH (3200520) DWR↗ stopped 2025-09-03 (55+ days) — call at HENRY BOLEN DITCH curtailing 100% of its decreed rate [heuristic-strong]
DURAN DITCH (3200551) DWR↗ stopped 2025-07-10 (21+ days) — call at HENRY BOLEN DITCH curtailing 100% of its decreed rate [heuristic-strong]
CHARLES MATTSON DITCH (3200520) DWR↗ stopped 2025-06-23 (49+ days) — call at LA PLATA RIVER BASIN curtailing 100% of its decreed rate [heuristic-strong]
BORD DITCH (3200512) DWR↗ stopped 2025-06-22 (28+ days) — call at LA PLATA RIVER BASIN curtailing 100% of its decreed rate [heuristic-strong]
BRIXEY-COMISKY DITCH (3200513) DWR↗ stopped 2025-06-22 (58+ days) — call at LA PLATA RIVER BASIN curtailing 100% of its decreed rate [heuristic-strong]
BURTON DITCH (3200517) DWR↗ stopped 2024-10-03 (386+ days) — call at SPRING CREEK DITCH curtailing 100% of its decreed rate [heuristic-strong]
GAFFORD DITCH NO 2 (3200564) DWR↗ stopped 2024-09-10 (15+ days) — call at HENRY BOLEN DITCH curtailing 100% of its decreed rate [heuristic-strong]
EARL HART DITCH (3200556) DWR↗ stopped 2024-09-09 (24+ days) — call at HENRY BOLEN DITCH curtailing 100% of its decreed rate [heuristic-strong]
HAMBELTON DITCH (3200574) DWR↗ stopped 2024-08-12 (6+ days) — call at HENRY BOLEN DITCH curtailing 100% of its decreed rate [heuristic-strong]
EARL HART DITCH (3200556) DWR↗ stopped 2024-08-04 (10+ days) — call at HENRY BOLEN DITCH curtailing 100% of its decreed rate [heuristic-strong]
COMISKY DITCH NO 1 (3200524) DWR↗ stopped 2024-07-24 (461+ days) — call at HENRY BOLEN DITCH curtailing 100% of its decreed rate [heuristic-strong]

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
ROCK CREEK DITCH (3200652) DWR↗	1888-03-20	38.8% / 14.5%	1.8% / 0.0%
WILSON DITCH (3200690) DWR↗	1888-06-01	32.5% / 11.7%	2.3% / 0.0%
BLACK DIKE DITCH (3200509) DWR↗	1889-04-15	29.7% / 11.7%	29.7% / 11.7%
HAMBELTON DITCH (3200574) DWR↗	1891-04-20	23.6% / 2.8%	2.3% / 0.0%
MTN UTE SAN JUAN DIVR (3200938) DWR↗	1868-03-02	100.0% / 100.0%	100.0% / 100.0%
COTTONWOOD DITCH NO 2 (3200529) DWR↗	1890-05-21	29.2% / 11.7%	29.2% / 11.7%
COTTONWOOD DITCH NO 1 (3200528) DWR↗	1891-01-25	23.6% / 2.8%	23.6% / 2.8%
BRUMLEY DRAW IRR DITCH (3200514) DWR↗	1889-04-20	29.2% / 11.7%	4.4% / 0.0%
EATON DITCH (3200558) DWR↗	1908-03-10	4.4% / 0.0%	2.3% / 0.0%
MURRAY-ZWICKER-TOZER D (3200634) DWR↗	1892-06-15	23.3% / 2.8%	2.3% / 0.0%
ISMAY DITCH (3200590) DWR↗	1955-01-01	2.3% / 0.0%	2.3% / 0.0%
SHUMWAY PERKINS PMPG STA (3200665) DWR↗	1972-01-18	2.3% / 0.0%	2.3% / 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 ~1980 — idleness that begins before then may be unreported use, not nonuse (flagged † below).

DAWSON DITCH (MCELMO) (3200537) DWR↗ (1943-04-25, 1.1 cfs decreed): last active 1974 — 51 years idle † predates modern reporting era — last recorded activity predates this basin's modern reporting era (~1980) -- early absence of record is weak evidence of nonuse
MURRAY PUMP AND PIPELINE (3200633) DWR↗ (1961-06-30, 0.1 cfs decreed): last active 1974 — 51 years idle † predates modern reporting era — last recorded activity predates this basin's modern reporting era (~1980) -- early absence of record is weak evidence of nonuse
PALMER PUMP AND DITCHES (3200639) DWR↗ (1920-12-31, 1.0 cfs decreed): last active 1976 — 49 years idle † predates modern reporting era — last recorded activity predates this basin's modern reporting era (~1980) -- early absence of record is weak evidence of nonuse
STRATTON DITCH (3200676) DWR↗ (1937-06-10, 0.2 cfs decreed): last active 1979 — 46 years idle † predates modern reporting era — last recorded activity predates this basin's modern reporting era (~1980) -- early absence of record is weak evidence of nonuse
OLD STAGE STATION DIVR (3200637) DWR↗ (1966-12-31, 0.6 cfs decreed): last active 1981 — 44 years idle
HARMON DITCH ALT PT #1 (3200776) DWR↗ (1950-08-19, 0.2 cfs decreed): last active 1983 — 42 years idle
MURPHY DIVERSION NO 1 (3200751) DWR↗ (1978-06-01, 0.5 cfs decreed): last active 1984 — 41 years idle
FETTERMAN HYDRAM (3200756) DWR↗ (1980-04-15, 0.1 cfs decreed): last active 1985 — 40 years idle
HARMON DITCH SPRUELL #2 (3200578) DWR↗ (1950-08-19, 0.1 cfs decreed): last active 1986 — 39 years idle
CULLEN DITCH (3200535) DWR↗ (1900-12-31, 2.5 cfs decreed): last active 1989 — 36 years idle

Compliance screens (145 advisory flags)

Screened 222 of 638 structures with rights (262 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.

HAMBELTON DITCH (3200574) DWR↗: Observed p99 daily rate 16.2 cfs (max 19.0) exceeds total decreed absolute 12.5 cfs across 36288 recorded day(s).
COTTONWOOD DITCH NO 2 (3200529) DWR↗: Observed p99 daily rate 15.0 cfs (max 17.0) exceeds total decreed absolute 10.0 cfs across 33971 recorded day(s).
BLACK DIKE DITCH (3200509) DWR↗: Observed p99 daily rate 13.9 cfs (max 16.9) exceeds total decreed absolute 13.1 cfs across 32347 recorded day(s).
COTTONWOOD DITCH NO 1 (3200528) DWR↗: Observed p99 daily rate 13.5 cfs (max 16.0) exceeds total decreed absolute 10.0 cfs across 26852 recorded day(s).
ROBERT B DUNHAM DITCH (3200651) DWR↗: Observed p99 daily rate 12.6 cfs (max 12.6) exceeds total decreed absolute 3.0 cfs across 2972 recorded day(s).
EATON DITCH (3200558) DWR↗: Observed p99 daily rate 8.4 cfs (max 11.2) exceeds total decreed absolute 6.0 cfs across 19763 recorded day(s).
MURRAY-ZWICKER-TOZER D (3200634) DWR↗: Observed p99 daily rate 8.4 cfs (max 10.3) exceeds total decreed absolute 6.0 cfs across 37422 recorded day(s).
OLD KANIGA DITCH (3200636) DWR↗: Observed p99 daily rate 8.0 cfs (max 8.0) exceeds total decreed absolute 2.0 cfs across 4142 recorded day(s).
SCHALLES DITCH (3200662) DWR↗: Observed p99 daily rate 7.0 cfs (max 8.5) exceeds total decreed absolute 4.0 cfs across 20069 recorded day(s).
BORD DITCH (3200512) DWR↗: Observed p99 daily rate 6.0 cfs (max 7.0) exceeds total decreed absolute 4.0 cfs across 18027 recorded day(s).

Seniority (top structures by decreed rate)

Structure	Senior priority date	Rights	Decreed abs (cfs)	Conditional?
ROCK CREEK DITCH (3200652) DWR↗	1888-03-20	3	39.3	—
WILSON DITCH (3200690) DWR↗	1888-06-01	8	28.5	yes
BLACK DIKE DITCH (3200509) DWR↗	1889-04-15	1	13.1	—
HAMBELTON DITCH (3200574) DWR↗	1891-04-20	2	12.5	yes
COTTONWOOD DITCH NO 1 (3200528) DWR↗	1891-01-25	1	10.0	—
COTTONWOOD DITCH NO 2 (3200529) DWR↗	1890-05-21	1	10.0	—
MTN UTE SAN JUAN DIVR (3200938) DWR↗	1868-03-02	1	10.0	—
BRUMLEY DRAW IRR DITCH (3200514) DWR↗	1889-04-20	2	7.3	—
EATON DITCH (3200558) DWR↗	1908-03-10	3	6.0	—
MURRAY-ZWICKER-TOZER D (3200634) DWR↗	1892-06-15	2	6.0	yes
ISMAY DITCH (3200590) DWR↗	1955-01-01	1	5.0	—
SHUMWAY PERKINS PMPG STA (3200665) DWR↗	1972-01-18	1	5.0	—
N E CARPENTER SEEPAGE D (3200635) DWR↗	1970-07-31	2	4.8	—
BORD DITCH (3200512) DWR↗	1910-04-20	2	4.0	—
POWELL AND CODY DITCH (3200644) DWR↗	1907-02-14	3	4.0	—

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

Water-court filings this month (division-wide)

4 applications in the 2026-07 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 2026-09-30 (25 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 4 filings, with excerpts

Case	What it asks	County	Excerpt
`2026CW3007` 3001335	change of water right	LA PLATA	2026CW3007 La Plata County, AMENDED APPLICATION FOR CHANGE OF WATER RIGHT AND NEW WATER RIGHTS. 1. Name and address of Applicants : Gilleland Enterprises, LLC and C&J Gravel Products, Inc. (“Applicants”)c/o John Gilleland 27661 Highway 160 Durango, CO 81301 jo…
`2026CW3016`	reasonable diligence	LA PLATA	2026CW3016 La Plata County, Application for Finding of Reasonable Diligence in the Florida River Watershed; Prior case no. 18CW3047: Applicant: The Bingel-Davis Gratitude Trust, u/a dated April 17, 2025, c/o Kimberly C. Perdue, Southwest Water and Property Law…
`2026CW3017`	—	LA PLATA	2026CW3017 La Plata County, (20CW3008, 13CW3027, 05CW90)…
`2026CW4`	—	ARCHULETA	2026CW4 Archuleta County, Jess E. Ketchum, 320 Stevens Lake Road, Pagosa Springs, CO 81147: Watson Reservoir (Reservoir Pump); Located in the SW 1/4 SE 1/4 of Section 5, T35N, R2W, NMPM, the axis intersects the East abutment at a point approximately 875 ft. No…

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: 8 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 11 streams, 3 agree. Know this water? Tell us →

Stream	This site routes it to	DWR routes it to
Alkali Canyon	the mainstem	Cross Canyon
Dawson Draw	the mainstem	Yellow Jacket Canyon
Brumley Draw	the mainstem	Dawson Draw
Alkali Canyon	the mainstem	McElmo Creek
Crow Canyon	the mainstem	McElmo Creek
Ritter Draw	the mainstem	Simon Draw
Simon Draw	the mainstem	McElmo Creek
Mud Creek	the mainstem	McElmo Creek

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