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Clear Creek

Division 1 · Water District 7 · As of 2026-10-10 00:34 MDT · 5 days ago · also known as Clear Creek Canyon

Who may take water from the Clear Creek, 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.

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How this page was built

Rebuilt 2026-10-14 12:14 UTC from 8,503 input files: two runs agree (output 2532f0e86de110d0…); not compared with the analysis served here (why?). The receipt

Clear Creek on the ground — the ditches, wells, reservoirs and gages of Water District 7 · clicktap anything for its record

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

37% of normal flow, week of 2026-09-28
2 calls the record places on it, 7 unsettled

The Clear Creek is well below normal for late September -- 37% of normal flow. 2 calls stand against it right now; the most senior right calling dates to 1861. DWR's statements do not settle whether 7 more calls reach it.

Snow and runoff

Source Independent agency measurement · fetched 2026-10-14 · 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
Loveland Basin11410 0.20.8 — May 2 (24.4 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 (1993–2026)

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 5 of the last 34 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: 2002, 2004, 2012, 2021, 2026.

Computed by this site from 1 SNOTEL site’ full daily records (NRCS AWDB, back to 1993). 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 — Clear Ck at Golden

NRCS's final issue (2026-06-01) calls it even odds that at least 52 kAF arrives over 06-01 to 09-30 — 52% of a normal season; almost certainly at least 42, probably not more than 63. Our own record at this gage shows 26 kAF actually delivered. New forecasts begin in January. How to read these numbers →

We test a record-based adjustment of the April benchmark at every graded point. Here it did not beat NRCS over 82 replayed seasons (17% typical miss unadjusted vs 20% adjusted), so none is shown — NRCS’s own forecast, unadjusted, is the best April benchmark available for this river. Why we test →

90% chance of at least70% chance of at least50% chance of at least30% chance of at least10% chance of at leastNormalObserved
4248525663 100 26

How good are these forecasts here? (1975–2025)

Grading every April issue against what the river then delivered, measured at this gage’s own record — 50 seasons: the median miss of the 50% forecast is 19%, with a high bias of 7%, and the observed volume landed inside the stated 10–90% band 78% 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 (1993–2026)

Across 34 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 71% 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 1.3).

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 37th-driest week 40 in 101 years of record at CLEAR CREEK AT DERBY (as of 2026-09-28; this week’s flow sits at the 37th 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, Broomfield County is 100% in D4 exceptional drought (2026-10-06). 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 1914, week by week

Each thin row is a year at CLEAR CREEK AT DERBY; 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 40 weeks recorded so far, 2026’s weekly trace most resembles 2002 (mean gap 13.4 percentile points; next closest 1954 (16.4), 1981 (16.7)). 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 Adams, Broomfield, Clear Creek, Denver, Gilpin, Grand, Jefferson, Summit 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 2004 — 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 (1615 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.

1635–1987: this river before anyone measured it

Tree rings record wet and dry years centuries before the first gage. This is the published reconstruction of annual flow at Clear Creek at Golden — 353 years, with its uncertainty band drawn, not implied — and the green line is the measured record at the same gage, water-year totals from DWR’s daily data, carrying the story through 2026. A reconstruction is an estimate, not a measurement: it answers “is this decade unusual in four centuries?”, and nothing in this site’s statistics uses it.

Why the two lines disagree on purpose: the trees were calibrated against naturalized flow — upstream diversions and storage added back — while the gage measures what the ditches left in the river. So the measured line running below the reconstruction is not an error; the gap is, roughly, human use. Over the 13 years both series cover, the river carried a median of 82% of its estimated natural flow past this gage. And because the reconstruction was fit to gage-era data, the overlap shows how well trees track the river (the authors report the models explain 63–76% of gage variance) — it is a calibration, not an independent test.

Woodhouse, C.A. and J.J. Lukas (2006), Multi-century tree-ring reconstructions of Colorado streamflow for water resource planning, Climatic Change 78; data via NOAA NCEI World Data Service for Paleoclimatology / TreeFlow. Source data ↗

This basin’s droughts, by its own record

DroughtSpanWeeks Trough percentileFlows recovered Water table back
unnamed dry spell 2026-04-27 → 2026-09-28 22 12th (2026-09-07) not yet —
the 2020-22 drought 2020-09-14 → 2021-05-10 34 19th (2021-01-11) 88 weeks —
the 2012-13 drought 2012-07-02 → 2013-10-07 66 13th (2012-09-03) 0 weeks —
unnamed dry spell 2006-01-09 → 2006-08-21 32 21st (2006-04-10) 23 weeks —
the 2002 drought 2002-03-11 → 2003-07-21 71 7th (2002-09-23) 0 weeks —
unnamed dry spell 1994-10-24 → 1995-06-19 34 17th (1994-12-12) 0 weeks 1 yr (5 wells, 1 still below)
the 1981 drought 1981-01-12 → 1982-10-11 91 7th (1982-04-26) 0 weeks 7 yr (6 wells, 2 still below)
unnamed dry spell 1978-12-18 → 1979-07-16 30 15th (1979-02-26) 1 week —
the 1977 drought 1977-06-20 → 1978-08-21 61 5th (1978-02-20) 48 weeks —
the 1977 drought 1976-04-26 → 1976-11-15 29 23rd (1976-07-12) 140 weeks —
the 1963-64 drought 1963-07-22 → 1963-12-09 20 22nd (1963-08-26) 3 weeks not yet (3 of 5 wells still below)
the 1950s drought 1957-02-04 → 1957-07-08 22 22nd (1957-03-11) 1 week —
the 1950s drought 1954-03-29 → 1955-10-17 81 10th (1954-09-20) 3 weeks —
the 1950s drought 1953-04-06 → 1953-08-24 20 24th (1953-05-18) 6 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.

What drought has cost here

Since 1991, federal crop insurance has paid $76,153,742 in drought-caused claims across Adams, Broomfield, Clear Creek, Denver, Gilpin, Grand, Jefferson, Summit counties — 51.9% of all insured crop losses there. The worst year was 2022 ($17,283,650).

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 (2,156 rights across 101 years of shared record), colored by that year’s wetness from the barcode above. Here the correlation is +0.16 — 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 — Clear Ck at Golden: even odds of at least 52 kAF over 06-01 to 09-30 — 52% 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
Loveland Basin11410 0.20.8 — May 2 (24.4 in)

Clear Ck at Golden — 06-01 to 09-30 volume, thousand acre-feet (chance the volume is AT LEAST this):

90%70%50%30%10%Normal
4248525663 100

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: 2 parent disagreements, 10 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 11 streams, 9 agree. Know this water? Tell us →

StreamThis site routes it toDWR routes it to
South Fork Ralston Creek the mainstem Ralston Creek
Coal Creek the mainstem Boulder Creek

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

Beaver Brook (11 mi) · Lena Gulch (10 mi) · Tucker Gulch (9 mi) · Little Dry Creek (9 mi) · Mill Creek (9 mi) · Guy Gulch (8 mi) · Elk Creek (6 mi) · Soda Creek (5 mi)

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