Saint Charles

Evolution of the network

Source Our computation, no independent reference · computed here from the screened DWR record Source Our computation, no independent reference · no independent reference; see /methods

This year, in context

In the weeks around 2026-07-06 (the newest reading on file), flows at the 4 ranked gages are running at a median 14% of their own long-term norm for this window — 4 below a typical year, 0 at or above. Driest relative to its record: SHURTZ DITCH ABOVE RYE CO, ranking 1st lowest of 20 years.

Gage flow trend & changepoints

None of the 12 gages with enough record shows a significant trend or a detected shift — which is itself the finding.

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

No gage shows a statistically significant trend or changepoint yet.

12 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. 4 gage(s) and 65 structure(s) report in 2026, but structure reporting only reached half its modern level around ~1912. 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 †.

Mass-balance (network closure) trend

Structure divrec-history backfill coverage as of the last check: 3% of 1860 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 (1974–2025)

Mass-balance kinks computed for every summer month back to 1974 (135 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.

No reach shows a statistically significant long-term gain/loss shift.

Groundwater now has its own tab: 80 monitored well(s), water-table trends, stream corridors, and the advisory depletion screen.

Reservoirs now has its own tab: 9 reservoir(s), end-of-year storage back to 1950, click-to-chart histories.

Cross-gage pattern fingerprint

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

Source DWR administrative record · verify at DWR groundwater wells ↗ Source DWR administrative record · verify at DWR well permits ↗

343 water-level measurements across 80 monitored well(s) — 18 alluvial, 0 bedrock — plus 5 administered well(s) reporting metered pumping.

Well map

3D aquifer x-ray

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

Water-table trends

Of 1 well(s) with enough record for a trend test: 1 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.

Source DWR administrative record · verify at DWR structure records ↗

9 reservoir(s) with 2,308 storage measurement(s), 1950–2014. Basin storage as of 2013-10-31 (the record's own end — reservoir records publish ~annually): 893 AF across 1 reservoir(s).

Reservoir map — how full is each vessel?

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.

Source Our computation, no independent reference · computed here from the screened DWR record Source Independent agency measurement · fetched 2026-09-08 · verify at U.S. Drought Monitor ↗

Right now

This is the 3rd-driest week 27 in 48 years of record at SAINT CHARLES RIVER AT VINELAND (as of 2026-06-29; this week’s flow sits at the 6th percentileRank against the record: a river at its 5th percentile is lower than it was in 95 of the past 100 years on this same date. for the date). On this week’s US Drought Monitor, Custer County is 100% in D3 extreme drought (2026-09-08). The law agrees: the most senior active call leaves 0% of this district’s decreed flow rights junior to the calling right this week.

Every year since 1978, week by week

Each thin row is a year at SAINT CHARLES RIVER AT VINELAND; 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.

This year against its analogs

Over the 27 weeks recorded so far, 2026’s weekly trace most resembles 2002 (mean gap 9.3 percentile points; next closest 1981 (11.5), 2012 (12.1)). The analog’s remainder is drawn as context — its ending is what happened to it, not a forecast for this year.

The Drought Monitor’s view since 2000

Mean share of area in each class across Custer, Pueblo 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 2005 — 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 (156 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

Detected mechanically: the 26-week smoothed percentile below the 30th for at least 20 weeks; recovered on regaining the 50th. The water-table clock compares each monitoring well against its own pre-drought median (the 3 years before onset) and dates the year the median well got back — the aquifer remembers longest, and “still below” is a finding, not a gap. 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 $3,076,450 in drought-caused claims across Custer, Pueblo counties — 6.5% of all insured crop losses there. The worst year was 2012 ($356,114).

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 (82 rights across 49 years of shared record), colored by that year’s wetness from the barcode above. Here the correlation is -0.21 — this basin tended to claim water in dry times, under scarcity pressure. 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.

Who serves it, who protects it

Two registers the site fetches on their own schedules, read for this district. Neither is a DWR record; each links its own page and its agency.

Public water systems here

Source Register of another agency · fetched 2026-09-08 · verify at EPA SDWIS ↗

7 systems touch this district (7 community systems reporting 128,166 people served, a figure that counts a wholesaler's customers twice); 1 of them carries an open health-based violation on EPA's record.

Instream-flow rights held by the state

Source Register of another agency · fetched 2026-09-13 · verify at CWCB instream flow program ↗

8 reaches over 53.3 miles, held by the Colorado Water Conservation Board so that water stays in the stream. Every reach, with its schedule and case →

• Saint Charles River, 13.0 mi: 3 (1/1 - 12/31) cfs (appropriated 1976, 76W4435) · dossier
• Greenhorn Creek, 6.8 mi: 1.5 (3/15 - 4/30), 4.75 (5/1 - 7/14), 0.85 (11/15 - 3/14), 1.5 (7/15 - 11/14) cfs (appropriated 1998, 98CW0154) · dossier
• Middle Creek, 6.72 mi: 5.1 (4/1 - 8/31), 2.8 (9/1 - 3/31) cfs (appropriated 2010, 10CW0057) · dossier
• Graneros Creek, 6.3 mi: 0.25 (1/1 - 12/31) cfs (appropriated 1998, 98CW0160) · dossier
• Greenhorn Creek, 6.3 mi: 1.25 (7/1 - 3/31), 2.25 (4/1 - 6/30) cfs (appropriated 1998, 98CW0148) · dossier
• Graneros Creek, 5.4 mi: 0.5 (3/15 - 4/30), 1.25 (5/1 - 8/14), 0.3 (12/1 - 3/14), 0.5 (8/15 - 11/30) cfs (appropriated 1998, 98CW0150) · dossier

and 2 more on the district's instream-flow page.

What the water is like -- USGS sensors right now, where it has been sampled, the impaired-waters list, and how the tap water here stands with EPA -- is on the Water quality tab.

Designated groundwater basins are on their own page.

Source Adjudicated record · verify at DWR water-right transactions ↗ Source Adjudicated record · verify at DWR net amounts ↗

Decreed rights on this network run from 1859-05-01 to 2022-12-13. Of the 20 structures with a yield estimate, the median one’s senior right was in priority 3% of a median irrigation season and 0% in a dry one. 25 abandonment screens and 58 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: 957 across 704 structure(s); 95 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: 3 of 3 measures (days under callA senior water right demanding its water, which requires everyone junior on that stream to stop diverting until it is satisfied., calls set, seniorityColorado shares water by date: the earlier the right, the stronger its claim when the river runs short. "First in time, first in right." of the controlling call) are moving toward more administration, none the other way.

Why diversions stopped — call-based explanations

Sustained diversion stops matched to senior administrative calls.

• PIONEER MIDDLE CREEK (1500517) DWR↗☆ stopped 2025-08-31 (61+ days) — call at MODEL DITCH curtailing 100% of its decreed rate [heuristic-strong]
• CARTER DITCH (1500557) DWR↗☆ stopped 2025-08-02 (16+ days) — call at TITSWORTH DITCH curtailing 100% of its decreed rate [heuristic-strong]
• HIGHLINE DITCH (1500541) DWR↗☆ stopped 2025-07-07 (58+ days) — call at LEWELLING-MCCORMICK curtailing 100% of its decreed rate [heuristic-strong]
• ROBINSON DITCH (1500549) DWR↗☆ stopped 2025-07-07 (21+ days) — call at LEWELLING-MCCORMICK curtailing 100% of its decreed rate [heuristic-strong]
• SHURTZ DITCH (1500553) DWR↗☆ stopped 2025-07-07 (49+ days) — call at LEWELLING-MCCORMICK curtailing 100% of its decreed rate [heuristic-strong]
• MESA DITCH (1500544) DWR↗☆ stopped 2025-07-06 (9+ days) — call at LEWELLING-MCCORMICK curtailing 100% of its decreed rate [heuristic-strong]
• A J LAMB DITCH (1500567) DWR↗☆ stopped 2025-07-02 (121+ days) — call at TITSWORTH DITCH curtailing 100% of its decreed rate [heuristic-strong]
• GRANEROS CANON DITCH (1500563) DWR↗☆ stopped 2025-06-15 (138+ days) — call at LUCERO DITCH curtailing 100% of its decreed rate [heuristic-strong]
• DUNBAUGH DITCH (1500545) DWR↗☆ stopped 2025-06-10 (42+ days) — call at LUCERO DITCH curtailing 81% of its decreed rate [heuristic-partial]
• A J LAMB DITCH (1500567) DWR↗☆ stopped 2025-06-04 (5+ days) — call at PULASKI DITCH curtailing 100% of its decreed rate [heuristic-strong]
• PIONEER MIDDLE CREEK (1500517) DWR↗☆ stopped 2025-06-03 (5+ days) — call at PULASKI DITCH curtailing 71% of its decreed rate [heuristic-partial]
• SHURTZ DITCH (1500553) DWR↗☆ stopped 2025-05-19 (18+ days) — call at HOEHNE 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.

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 ~1912 — idleness that begins before then may be unreported use, not nonuse (flagged † below).

• GREENHORN HIGHLINE DITCH (1500539) DWR↗☆ (1859-05-01, 10.9 cfs decreed): last active 1934 — 91 years idle
• FISHER CANON DITCH NO 2 (1500560) DWR↗☆ (1893-06-27, 2.0 cfs decreed): last active 1939 — 86 years idle
• MEXICAN DITCH (1500585) DWR↗☆ (1867-02-20, 2.0 cfs decreed): last active 1957 — 68 years idle
• MCDANIEL DITCH NO 3 (1500569) DWR↗☆ (1879-11-30, 0.1 cfs decreed): last active 1973 — 52 years idle
• MOORE'S SPRING PIPELINE (1500617) DWR↗☆ (1906-06-30, 0.5 cfs decreed): last active 1973 — 52 years idle
• DAVIS DITCH (1500533) DWR↗☆ (1873-06-01, 0.9 cfs decreed): last active 1974 — 51 years idle
• COLORADO CITY WELL NO 3 (1505593) DWR↗☆ (1965-08-25, 0.6 cfs decreed): last active 1974 — 51 years idle
• CRAWFORD & SMYTHE DITCH (1500531) DWR↗☆ (1870-03-01, 3.7 cfs decreed): last active 1975 — 50 years idle
• PIERSON SPRING DITCH (1500619) DWR↗☆ (1868-05-01, 1.8 cfs decreed): last active 1975 — 50 years idle
• IRON SPRINGS PIPELINE (1500642) DWR↗☆ (1901-12-31, 0.3 cfs decreed): last active 1982 — 43 years idle

Compliance screens (58 advisory flags)

Screened 105 of 704 structures with rights (117 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.

• DOTSON DITCH NO 1 (1500507) DWR↗☆: Observed p99 daily rate 26.2 cfs (max 266.0) exceeds total decreed absolute 26.0 cfs across 47152 recorded day(s).
• A J LAMB DITCH (1500567) DWR↗☆: Observed p99 daily rate 11.2 cfs (max 15.5) exceeds total decreed absolute 7.3 cfs across 7705 recorded day(s).
• GREENHORN HIGHLINE DITCH (1500539) DWR↗☆: Observed p99 daily rate 11.0 cfs (max 11.0) exceeds total decreed absolute 10.9 cfs across 2376 recorded day(s).
• HICKLIN DITCH "A" (1500538) DWR↗☆: Observed p99 daily rate 10.0 cfs (max 29.4) exceeds total decreed absolute 0.7 cfs across 38112 recorded day(s).
• HICKLIN DITCH "B" (1500540) DWR↗☆: Observed p99 daily rate 10.0 cfs (max 20.0) exceeds total decreed absolute 1.7 cfs across 2732 recorded day(s).
• CRAWFORD & SMYTHE DITCH (1500531) DWR↗☆: Observed p99 daily rate 6.0 cfs (max 8.0) exceeds total decreed absolute 3.7 cfs across 9180 recorded day(s).
• STANLEY DITCH NO 1 (1500554) DWR↗☆: Observed p99 daily rate 5.8 cfs (max 38.0) exceeds total decreed absolute 1.5 cfs across 5902 recorded day(s).
• WAGNER DITCH (1500524) DWR↗☆: Observed p99 daily rate 4.2 cfs (max 8.0) exceeds total decreed absolute 1.5 cfs across 10596 recorded day(s).
• MARINCICH PUMP (1500525) DWR↗☆: Observed p99 daily rate 4.2 cfs (max 4.6) exceeds total decreed absolute 0.8 cfs across 1454 recorded day(s).
• CHASE DITCH (1500506) DWR↗☆: Observed p99 daily rate 4.0 cfs (max 11.5) exceeds total decreed absolute 2.0 cfs across 7370 recorded day(s).

Seniority (top structures by decreed rate)

Recent inventory & legal-document changes

• 2026-09-11 — call set: TENASSEE DITCH (39464)
• 2026-09-11 — call set: TROUT CREEK DITCH CO (39466)
• 2026-09-11 — call set: PBWW NORTHSIDE INTAKE (39465)
• 2026-09-11 — call set: FORT LYON CANAL (39463)
• 2026-09-11 — call released: 39449
• 2026-09-11 — call released: 39458
• 2026-09-11 — call released: 39428
• 2026-09-11 — call released: 39460

Water-court filings this month (division-wide)

6 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 (15 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.

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.

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.

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.