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Wet Mountain Valley

Division 2 · Water District 13 · As of 2026-09-19 05:20 MDT · 4 weeks ago

Who may take water from the Wet Mountain Valley, who is calling for it today, and how it is running, compiled from Colorado Division of Water Resources records. Click anything on the map for its record.

Live · machine-built

Wet Mountain Valley on the ground — the ditches, wells, reservoirs and gages of Water District 13 · clicktap anything for its record

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

16% of normal flow, week of 2026-09-21
0 calls the record places on it, 20 unsettled

The Grape Creek is critically low for late September -- 16% of normal flow. No call that the record places on it is active right now. DWR's statements do not settle whether 20 more calls reach it.

Snow and runoff

Source Independent agency measurement · fetched 2026-10-15 · verify at NRCS report generator ↗ Source Our computation, scored against a reference · NRCS forecast, graded here against the gage record

Snow-water equivalent, WY2027

SNOTEL siteElev (ft)SWE (in)Median (in)% of medianTypical peak
South Colony10790 0.80.3 — April 23 (20.9 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 (1992–2026)

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 11 of the last 35 winters the snow never came — the pack peaked below 80% of its median. In 0 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.

The snow never came: 1996, 2000, 2002, 2006, 2012, 2013, 2015, 2018, 2020, 2025, 2026.

Computed by this site from 1 SNOTEL site’ full daily records (NRCS AWDB, back to 1992). 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 — Grape Ck nr Westcliffe

NRCS's final issue (2026-06-01) calls it even odds that at least 2 kAF arrives over 06-01 to 09-30 — 25% of a normal season; almost certainly at least 0, probably not more than 6. Our own record at this gage shows 1 kAF actually delivered. 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 5 kAF over 04-01 to 09-30. 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 69 past seasons here (1981–2025), never seeing the year it predicts, the adjustment cut the typical April miss from 40% to 38%. 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 least70% chance of at least50% chance of at least30% chance of at least10% chance of at leastNormalObserved
01246 10 1

How good are these forecasts here? (1980–2025)

Grading every April issue against what the river then delivered, measured at this gage’s own record — 44 seasons: the median miss of the 50% forecast is 40%, with a high bias of 15%, and the observed volume landed inside the stated 10–90% band 68% of the time (a calibrated forecast would say 80%).

Computed by this site: NRCS's archived April issues (their period as issued each year) against the observed volume in DWR’s published record; years with under 90% daily coverage are dropped, not summed. A grade of the forecast, never of the forecasters — these are hard rivers. How this point ranks among every graded Colorado forecast point →

What April snow has meant for this river (1992–2026)

Across 35 measured years, the season’s water has closely followed the April snowpack: a year opening April with 80% of median snow has typically gone on to deliver about 56% of a normal season (a snow-to-runoff elasticityHow strongly one number moves with another. A snow-to-runoff elasticity of 1.5 means a 10% shortfall in April snowpack has typically become a 15% shortfall in the season's water. of 2.1).

Computed by this site: the district’s April 1 SWE (% of each SNOTEL site’s own-record median) against the observed April–July volume at this gage (% of its median season) — a fixed window every year, unlike the forecast grades above, which use each issue’s own period. The slope is fit so single wild years can’t steer it (Theil–Sen, log space); years missing 10% of their days are dropped.

Drought

Source Our computation, no independent reference · computed here from the screened DWR record Source Independent agency measurement · fetched 2026-10-06 · verify at U.S. Drought Monitor ↗

Right now

This is the 16th-driest week 39 in 99 years of record at GRAPE CREEK NEAR WESTCLIFFE, CO. (as of 2026-09-21; this week’s flow sits at the 16th 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, Chaffee County is 75% in D4 exceptional drought (2026-10-06). 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 1925, week by week

Each thin row is a year at GRAPE CREEK NEAR WESTCLIFFE, 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.

This year against its analogs

Over the 39 weeks recorded so far, 2026’s weekly trace most resembles 2018 (mean gap 9.8 percentile points; next closest 2025 (14.6), 1954 (15.0)). 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 Chaffee, Custer, Fremont 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 (131 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

DroughtSpanWeeks Trough percentileFlows recovered Water table back
unnamed dry spell 2025-08-11 → 2026-01-19 23 25th (2025-08-25) 0 weeks —
the 2020-22 drought 2020-06-15 → 2021-03-08 38 15th (2020-09-21) 10 weeks not yet (8 of 13 wells still below)
the 2018 drought 2018-07-16 → 2019-04-15 39 11th (2018-10-08) 8 weeks not yet (8 of 12 wells still below)
the 2012-13 drought 2011-06-06 → 2013-11-18 128 12th (2013-01-14) 36 weeks 7 yr (18 wells, 8 still below)
the 2002 drought 2002-04-29 → 2003-07-28 65 14th (2002-08-26) 55 weeks 2 yr (6 wells)
unnamed dry spell 1996-08-19 → 1997-01-27 23 25th (1996-10-14) 12 weeks 10 yr (6 wells, 2 still below)
the 1977 drought 1978-07-03 → 1979-05-07 44 13th (1978-10-09) 4 weeks 2 yr (20 wells, 5 still below)
unnamed dry spell 1974-06-24 → 1975-04-28 44 16th (1974-10-21) 8 weeks 4 yr (32 wells, 9 still below)
unnamed dry spell 1972-06-05 → 1972-12-25 29 26th (1972-08-28) 15 weeks 18 yr (33 wells, 15 still below)
unnamed dry spell 1967-04-17 → 1967-09-04 20 26th (1967-05-29) 3 weeks —
the 1963-64 drought 1963-02-18 → 1965-06-28 123 2nd (1964-03-02) 1 week —
unnamed dry spell 1959-01-05 → 1959-08-24 33 14th (1959-03-30) 6 weeks —
unnamed dry spell 1958-03-03 → 1958-08-11 23 20th (1958-03-31) 60 weeks —
the 1950s drought 1956-07-16 → 1957-07-15 52 7th (1956-12-10) 0 weeks —

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.

When this basin claimed its water

Every bar is a year’s new appropriations (516 rights across 101 years of shared record), colored by that year’s wetness from the barcode above. Here the correlation is -0.11 — 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.

Snowpack — 1 SNOTEL site report here. Runoff outlook — Grape Ck nr Westcliffe: even odds of at least 2 kAF over 06-01 to 09-30 — 25% 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 siteElev (ft)SWE (in)Median (in)% of medianTypical peak
South Colony10790 0.80.3 — April 23 (20.9 in)

Grape Ck nr Westcliffe — 06-01 to 09-30 volume, thousand acre-feet (chance the volume is AT LEAST this):

90%70%50%30%10%Normal
01246 10

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: 7 parent disagreements, 7 sizable streams 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 21 streams, 14 agree. Know this water? Tell us →

StreamThis site routes it toDWR routes it to
North Branch Middle Colony Creek the mainstem South Colony Creek
Goodwin Creek the mainstem Taylor Creek
Middle Taylor Creek the mainstem Taylor Creek
Alvarado Creek the mainstem Spring Creek
Cottonwood Creek the mainstem Alvarado Creek
South Colony Creek the mainstem no parent named
Cottonwood Creek the mainstem Froze Creek

Sizable streams DWR maps here that this network does not carry:

Wilmer Gulch (14 mi) · Johnson Gulch (10 mi) · Crystal Falls Creek (4 mi) · Spring Creek (4 mi) · Democrat Creek (4 mi) · Music Pass Creek (3 mi) · Spring Creek (3 mi)

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