Hydrohistorian
Mancos River Basin on the ground — the ditches, wells, reservoirs and gages of Water District 34 · clicktap anything for its record
Browse this district’s ditches, gages, reservoirs, wells and springs as a list.
The Mancos River is critically low for late June -- 17% of normal flow. 17 calls stand against it right now; the most senior right calling dates to 1876. This year's runoff outlook, issued 2026-06-01, called for 50% of normal.
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.
Schematic
Historical
Evolution of the network
Trends
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 31% of their own long-term norm for this window — 6 below a typical year, 1 at or above. Driest relative to its record: MANCOS RIVER NEAR TOWAOC, CO., ranking 1st lowest of 99 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 21:19 from 19 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 19 gages with enough record, 1 is trending down and 2 up, and 3 carry a detected shift. The clearest is Towaoc Canal (East/West Meter Readouts), its annual mean flow changing +5.63 cfs per decade (+34.8% of its median annual flow) over 16 years (p=0.0003). The other 16 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 |
|---|---|---|---|---|---|
|
▸
Towaoc Canal (East/West Meter Readouts) TOWEASCO |
↑ increasing | +5.63 cfs +34.8% | p<0.001 | 16 | ~2004 |
|
▸
Towaoc Canal West Channel TOWWESCO |
↑ increasing | +5.34 cfs +32.1% | p=0.006 | 16 | ~2005 |
|
▸
Mancos River near Towaoc MANTOWCO |
↓ decreasing | -2.48 cfs -7.1% | p=0.016 | 95 | ~1999 |
16 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. 7 gage(s) and 47 structure(s) report in 2026, but structure reporting only reached half its modern level around ~1974. 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 |
| 1930s | 2 | 0 |
| 1940s | 3 | 0 |
| 1950s | 2 | 34 |
| 1960s | 1 | 33 |
| 1970s | 2 | 50 |
| 1980s | 3 | 70 |
| 1990s | 4 | 70 |
| 2000s | 7 | 75 |
| 2010s | 8 | 56 |
| 2020s | 9 | 47 |
Mass-balance (network closure) trend
Structure divrec-history backfill coverage as of the last check: 30% of 142 schematic-relevant structures. 1 year(s) clear the 30% coverage gate so far (2008–2008) -- 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 (1950–2026)
Mass-balance kinks computed for every summer month back to 1950 (281 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.
- JACKSON GULCH RES OUTLET CANAL TO W MANCOS RIVER: reach shifted from +11 cfs to +13 cfs summer mean (more gaining, p=0.043, 11 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=-0.53) -- part of it may be unaccounted water becoming accounted, not hydrologic change]
Groundwater now has its own tab: 13 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 1950, click-to-chart histories.
Cross-gage pattern fingerprint
Over the 11-year window with full coverage (2016–2026), the dominant shared pattern across 3 gage(s) explains 93% of year-to-year variance (almost certainly a basin-wide climate/snowpack driver).
All gages in this window move with the shared pattern -- no localized outlier.
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 | 30% of schematic structures have data |
Independent check: PASS — 100.0000% agreement across 286,733 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 — 99.98% day-level agreement with USGS's own published records for the same gages, across 9 co-listed station(s) and 63,011 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.
19 gage(s) / 133,981 daily values (1921-04-01–2026-07-06); 124 structure(s) with diversion records; 495 with decreed rights. Methodology has not yet had independent expert review — treat every figure as an advisory screen, not an administrative or legal conclusion.
Groundwater
23 water-level measurements across 13 monitored well(s) — 5 alluvial, 0 bedrock — plus 2 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.
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.
JACKSON GULCH RES OUTLET CANAL TO W MANCOS RIVER: 0 alluvial well(s) nearby. Glover screen: 0.0 cfs of nearby metered alluvial pumping → est. lagged depletion 0.0–0.0 cfs (uncalibrated T/S ranges; flagged for SPDSS calibration, AWAS cross-check, and expert review — DWR's AWAS is the authority).
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.
Reservoirs
15 reservoir(s) with 4,355 storage measurement(s), 1950–2024. Basin storage as of 2023-10-31 (the record's own end — reservoir records publish ~annually): 1,553 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) | |
|---|---|---|---|---|---|
| ▸ JACKSON GULCH RESERVOIR (3403589) | 4,024 | 2011-10-31 | — | — | dossier → |
| ▸ BAUER RESERVOIR NO 2 (3403586) | 1,136 | 2023-10-31 | — | — | dossier → |
| ▸ MATHEWS DITCH (3400546) | 666 | 2003-10-31 | — | — | dossier → |
| ▸ BAUER RESERVOIR NO 1 (3403585) | 212 | 2023-10-31 | — | — | dossier → |
| ▸ WEBER RESERVOIR (3403594) | 205 | 2023-10-31 | — | — | dossier → |
| ▸ L A BAR RESERVOIR (3403590) | 43 | 2015-10-04 | — | — | dossier → |
| ▸ COPPINGER NO 1 RESERVOIR (3403587) | 26 | 2015-10-21 | — | — | dossier → |
| ▸ CUTTHROAT POND (3403745) | 18 | 2015-10-17 | — | — | dossier → |
Snow and runoff
Snow-water equivalent, WY2026
No snow on the ground — normal for the date; the snow year begins in October. The chart shows the full water year just ending.
| SNOTEL site | Elev (ft) | SWE (in) | Median (in) | % of median | Typical peak |
|---|---|---|---|---|---|
| Mancos | 10020 | 0.1 | 0.0 | — | March 23 (16.3 in) |
NRCS SNOTEL, daily. Sites are assigned to the district whose boundary contains them — the snow that feeds this district can also sit in a neighboring headwater district.
Two ways a snow year goes wrong (1995–2026)
A bad snow year here comes in two flavors (both called snow droughtA winter that shorts the snowpack. It happens two ways: a dry one, where the snow never comes, and a warm one, where near-normal snow falls but melts off weeks early -- and the river feels them differently.), and the river feels them differently. In 10 of the last 32 winters the snow never came — the pack peaked below 80% of its median. In 1 more, the snow came but left early — a near-normal peak melted out two weeks or more ahead of its usual date, sending the water down before the season needed it. This year was one of the dry ones: the pack peaked at 50% of median.
The snow never came: 1999, 2002, 2006, 2007, 2014, 2015, 2018, 2021, 2025, 2026. The snow left early: 2012.
Computed by this site from 1 SNOTEL site’ full daily records (NRCS AWDB, back to 1995). Each year is measured against each site’s own multi-decade median — not the 1991–2020 normal the chart above uses — so the 1980s grade against a fair baseline. Peak and melt-out need 85% of the season’s days on the record; thin years are dropped, not guessed. Derived from snow measurements alone — it cannot tell dry-from-warm causes apart, only what the snowpack did.
Runoff outlook — Mancos R nr Mancos
NRCS's final issue (2026-06-01) calls it even odds that at least 1 kAF arrives over 06-01 to 07-31 — 50% of a normal season; almost certainly at least 0, probably not more than 2. New forecasts begin in January. How to read these numbers →
The record-adjusted April benchmark
NRCS’s April issue (2026-04-01) called even odds at 4 kAF over 04-01 to 07-31. Re-anchoring that number on this river’s own history — how its April issues have verified, the winter’s baseflow, and the district’s April 1 snowpack — moves it to 2 kAF. The river delivered 2 kAF.
Computed by this site — not an NRCS number, and shown only because it earned it: replayed over 60 past seasons here (1995–2026), never seeing the year it predicts, the adjustment cut the typical April miss from 46% to 36%. At points where it does not beat NRCS, no adjusted number appears. Coefficients are frozen each August; the model never changes mid-season. Method and honest limits →
| 90% chance of at least | 70% chance of at least | 50% chance of at least | 30% chance of at least | 10% chance of at least | Normal |
|---|---|---|---|---|---|
| 0 | 0 | 1 | 1 | 2 | 1 |
Drought
Right now
This is the 32nd-driest week 27 in 99 years of record at MANCOS RIVER NEAR TOWAOC, CO. (as of 2026-06-29; this week’s flow sits at the 17th 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 99% of this district’s decreed flow rights junior to the calling right this week.
Every year since 1921, week by week
Each thin row is a year at MANCOS RIVER NEAR TOWAOC, 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 Montezuma county — 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 2006 — 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 (376 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 | 2025-02-24 → 2026-07-06 | 71 | 13th (2026-07-06) | not yet |
| unnamed dry spell | 2024-01-01 → 2024-10-07 | 40 | 26th (2024-06-10) | not yet |
| the 2020-22 drought | 2019-12-30 → 2022-10-17 | 146 | 1st (2021-04-26) | 34 weeks |
| the 2018 drought | 2018-02-19 → 2019-07-08 | 72 | 4th (2019-02-25) | 0 weeks |
| unnamed dry spell | 2015-02-16 → 2015-08-24 | 27 | 16th (2015-05-11) | 6 weeks |
| the 2012-13 drought | 2014-03-24 → 2014-11-24 | 35 | 14th (2014-06-16) | 45 weeks |
| the 2012-13 drought | 2012-06-25 → 2013-11-18 | 73 | 11th (2013-01-21) | 1 week |
| the 2002 drought | 2002-03-11 → 2003-11-10 | 87 | 8th (2003-03-10) | 63 weeks |
| the 2002 drought | 2000-10-02 → 2001-07-16 | 41 | 23rd (2001-03-05) | 184 weeks |
| unnamed dry spell | 1996-06-17 → 1996-11-25 | 23 | 23rd (1996-08-19) | 0 weeks |
| unnamed dry spell | 1990-01-29 → 1990-11-12 | 41 | 15th (1990-06-25) | 1 week |
| the 1977 drought | 1977-03-28 → 1978-06-19 | 64 | 9th (1977-07-04) | 0 weeks |
| unnamed dry spell | 1974-06-24 → 1975-02-10 | 33 | 14th (1974-10-14) | 7 weeks |
| unnamed dry spell | 1972-07-17 → 1972-12-11 | 21 | 19th (1972-08-28) | 0 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 (136 rights across 99 years of shared record), colored by that year’s wetness from the barcode above. Here the correlation is +0.1 — 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.
Legal
Decreed rights on this network run from 1868-03-02 to 2024-12-18. Of the 20 structures with a yield estimate, the median one’s senior right was in priority 61% of a median irrigation season and 29% in a dry one. 7 abandonment screens and 44 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: 651 across 495 structure(s); 34 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.
- JACKSON GULCH INLET CNL (3400535) DWR↗ stopped 2025-10-21 (10+ days) — call at LA PLATA RIVER BASIN curtailing 98% of its decreed rate [heuristic-partial]
- GILES DITCH (3400530) DWR↗ stopped 2025-09-22 (28+ days) — call at HENRY BOLEN DITCH curtailing 67% of its decreed rate [heuristic-partial]
- JACKSON GULCH INLET CNL (3400535) DWR↗ stopped 2025-09-02 (37+ days) — call at HENRY BOLEN DITCH curtailing 100% of its decreed rate [heuristic-partial]
- E C SMITH DITCH (3400521) DWR↗ stopped 2025-09-01 (60+ days) — call at HENRY BOLEN DITCH curtailing 100% of its decreed rate [heuristic-strong]
- LEE DITCH (3400543) DWR↗ stopped 2025-09-01 (21+ days) — call at HENRY BOLEN DITCH curtailing 100% of its decreed rate [heuristic-strong]
- NO 6 DITCH (3400552) DWR↗ stopped 2025-09-01 (60+ days) — call at HENRY BOLEN DITCH curtailing 100% of its decreed rate [heuristic-strong]
- HENRY BOLEN DITCH (3400534) DWR↗ stopped 2025-08-31 (61+ days) — call at HENRY BOLEN DITCH curtailing 100% of its decreed rate [heuristic-strong]
- BAUER RESERVOIR D NO 2 (3400504) DWR↗ stopped 2025-08-28 (64+ days) — call at HENRY BOLEN DITCH curtailing 100% of its decreed rate [heuristic-strong]
- BEAVER DITCH (3400505) DWR↗ stopped 2025-08-17 (75+ days) — call at SPRING CREEK DITCH curtailing 100% of its decreed rate [heuristic-strong]
- EAST MANCOS HIGHLINE DITCH (3400522) DWR↗ stopped 2025-07-31 (92+ days) — call at HENRY BOLEN DITCH curtailing 100% of its decreed rate [heuristic-strong]
- LONG PARK DITCH (3400544) DWR↗ stopped 2025-07-10 (113+ days) — call at HENRY BOLEN DITCH curtailing 100% of its decreed rate [heuristic-strong]
- SMOUSE DITCH (3400567) DWR↗ stopped 2025-06-30 (123+ 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 |
|---|---|---|---|
| JACKSON GULCH INLET CNL (3400535) DWR↗ | 1876-05-15 | 100.0% / 48.1% | 2.3% / 0.0% |
| WEBBER DITCH (3400576) DWR↗ | 1875-05-15 | 100.0% / 100.0% | 2.3% / 0.0% |
| MANCOS RIVER MESA VERDE (3401904) DWR↗ | 1995-01-01 | 2.3% / 0.0% | 2.3% / 0.0% |
| RATLIFF AND ROOT DITCH (3400554) DWR↗ | 1875-05-15 | 100.0% / 100.0% | 2.3% / 0.0% |
| RUSH RESERVOIR DITCH (3400560) DWR↗ | 1886-05-15 | 41.4% / 17.3% | 23.3% / 2.8% |
| MTN UTE NAVAJO WASH DIVR (3400690) DWR↗ | 1868-03-02 | 2.3% / 0.0% | 2.3% / 0.0% |
| HENRY BOLEN DITCH (3400534) DWR↗ | 1878-05-15 | 61.2% / 31.3% | 1.8% / 0.0% |
| BEAVER DITCH (3400505) DWR↗ | 1880-05-15 | 60.5% / 27.6% | 23.3% / 2.8% |
| SHEEK DITCH (3400565) DWR↗ | 1878-05-15 | 61.2% / 31.3% | 1.8% / 0.0% |
| LEE DITCH (3400543) DWR↗ | 1878-05-15 | 61.2% / 31.3% | 23.3% / 2.8% |
| WEBER RESERVOIR INLET D (3400577) DWR↗ | 1892-05-15 | 23.3% / 2.8% | 4.4% / 0.0% |
| CARPENTER AND MITCHELL D (3400508) DWR↗ | 1882-05-15 | 49.8% / 19.2% | 23.3% / 2.8% |
Abandonment radar (7 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 ~1974 — idleness that begins before then may be unreported use, not nonuse (flagged † below).
- SPRING DITCH (3400570) DWR↗ (1901-12-31, 2.0 cfs decreed): last active 1976 — 27 years idle
- MARYS DITCH (3400601) DWR↗ (1953-12-31, 0.2 cfs decreed): last active 1983 — 20 years idle
- SPENCER RESERVOIR (3403593) DWR↗ (1940-12-12, 0.0 cfs decreed): last active 1986 — 17 years idle
- TED WILLDEN DITCH (3400572) DWR↗ (1880-12-31, 2.1 cfs decreed): last active 1989 — 14 years idle
- WESTON AND JARRETT DITCH (3400580) DWR↗ (1878-05-15, 1.0 cfs decreed): last active 1989 — 14 years idle
- R W OGLE DITCH (3400561) DWR↗ (1912-04-01, 1.0 cfs decreed): last active 1991 — 12 years idle
- HASTINGS PUMP (3400635) DWR↗ (1988-09-01, 0.1 cfs decreed): last active 1992 — 11 years idle
Compliance screens (44 advisory flags)
Screened 76 of 495 structures with rights (94 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.
- BAUER RESERVOIR D NO 2 (3400504) DWR↗: Observed p99 daily rate 20.6 cfs (max 46.0) exceeds total decreed absolute 0.5 cfs across 21320 recorded day(s).
- HENRY BOLEN DITCH (3400534) DWR↗: Observed p99 daily rate 16.0 cfs (max 23.0) exceeds total decreed absolute 14.6 cfs across 62653 recorded day(s).
- VEITS DITCH (3400574) DWR↗: Observed p99 daily rate 10.0 cfs (max 18.6) exceeds total decreed absolute 5.2 cfs across 21611 recorded day(s).
- CRYSTAL CREEK DITCH (3400514) DWR↗: Observed p99 daily rate 8.6 cfs (max 18.0) exceeds total decreed absolute 4.0 cfs across 28946 recorded day(s).
- GILES DITCH (3400530) DWR↗: Observed p99 daily rate 8.1 cfs (max 12.0) exceeds total decreed absolute 6.1 cfs across 38794 recorded day(s).
- EAST MANCOS HIGHLINE DITCH (3400522) DWR↗: Observed p99 daily rate 8.0 cfs (max 12.3) exceeds total decreed absolute 5.6 cfs across 22239 recorded day(s).
- FIELD DITCH (3400525) DWR↗: Observed p99 daily rate 7.0 cfs (max 9.0) exceeds total decreed absolute 0.9 cfs across 17599 recorded day(s).
- A T ROBB NORTH DITCH (3400501) DWR↗: Observed p99 daily rate 5.0 cfs (max 5.0) exceeds total decreed absolute 2.0 cfs across 948 recorded day(s).
- MATHEWS DITCH (3400546) DWR↗: Observed p99 daily rate 5.0 cfs (max 5.0) exceeds total decreed absolute 3.0 cfs across 1800 recorded day(s).
- FRANK DITCH (3400527) DWR↗: Observed p99 daily rate 4.4 cfs (max 6.0) exceeds total decreed absolute 3.7 cfs across 30723 recorded day(s).
Seniority (top structures by decreed rate)
| Structure | Senior priority date | Rights | Decreed abs (cfs) | Decreed abs (AF) | Conditional? |
|---|---|---|---|---|---|
| JACKSON GULCH INLET CNL (3400535) DWR↗ | 1876-05-15 | 10 | 526.2 | 0 | — |
| WEBBER DITCH (3400576) DWR↗ | 1875-05-15 | 18 | 52.1 | 0 | — |
| MANCOS RIVER MESA VERDE (3401904) DWR↗ | 1995-01-01 | 1 | 45.0 | 0 | — |
| RATLIFF AND ROOT DITCH (3400554) DWR↗ | 1875-05-15 | 20 | 39.8 | 0 | — |
| RUSH RESERVOIR DITCH (3400560) DWR↗ | 1886-05-15 | 2 | 20.5 | 0 | — |
| MTN UTE NAVAJO WASH DIVR (3400690) DWR↗ | 1868-03-02 | 1 | 15.0 | 0 | — |
| HENRY BOLEN DITCH (3400534) DWR↗ | 1878-05-15 | 8 | 14.6 | 0 | — |
| BEAVER DITCH (3400505) DWR↗ | 1880-05-15 | 10 | 14.1 | 0 | — |
| SHEEK DITCH (3400565) DWR↗ | 1878-05-15 | 8 | 13.5 | 0 | — |
| LEE DITCH (3400543) DWR↗ | 1878-05-15 | 10 | 12.5 | 0 | — |
| WEBER RESERVOIR INLET D (3400577) DWR↗ | 1892-05-15 | 5 | 11.5 | 0 | — |
| CARPENTER AND MITCHELL D (3400508) DWR↗ | 1882-05-15 | 4 | 11.2 | 0 | — |
| LONG PARK DITCH (3400544) DWR↗ | 1882-05-15 | 6 | 11.0 | 0 | — |
| LEE AND BURKE DITCH (3400542) DWR↗ | 1874-07-01 | 4 | 7.9 | 0 | — |
| SPENCER DITCH (3400569) DWR↗ | 1937-08-08 | 1 | 7.4 | 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… |
Call cascade
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
DWR administration numbers encode appropriation and adjudication dates; lower is more senior.
Snowpack — no snow on the ground at 1 SNOTEL site — normal for the date; the snow year begins in October and typically peaks around March 23. Runoff outlook — Mancos R nr Mancos : even odds of at least 1 kAF over 06-01 to 07-31 — 50% of a normal season, per NRCS, issued 2026-06-01 — the season’s final; new forecasts begin in January. Full snow & runoff picture — charts, forecast history and how the forecasts have verified →
Sites, exceedance bands and sources
| SNOTEL site | Elev (ft) | SWE (in) | Median (in) | % of median | Typical peak |
|---|---|---|---|---|---|
| Mancos | 10020 | 0.1 | 0.0 | — | March 23 (16.3 in) |
Mancos R nr Mancos — 06-01 to 07-31 volume, thousand acre-feet (chance the volume is AT LEAST this):
| 90% | 70% | 50% | 30% | 10% | Normal |
|---|---|---|---|---|---|
| 0 | 0 | 1 | 1 | 2 | 1 |
Snow-water equivalent and medians (1991–2020) from NRCS SNOTEL; seasonal volume forecasts from the NRCS National Water and Climate Center. Sites and forecast points are assigned to the district whose boundary contains them — snowpack that feeds this district can also sit in a neighboring headwater district. Toggle the Snow chip on the map above to see the sites.
Topology cross-check: 5 parent disagreements, 1 sizable stream not on this network (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 7 streams, 2 agree. Know this water? Tell us →
| Stream | This site routes it to | DWR routes it to |
|---|---|---|
| Chicken Creek | the mainstem | Mancos River |
| Middle Mancos River | the mainstem | East Mancos River |
| East Mancos River | the mainstem | Mancos River |
| Mud Creek | the mainstem | Mancos River |
| Perkins Draw | the mainstem | Seabury Draw |
Sizable streams DWR maps here that this network does not carry:
Crystal Creek (4 mi)