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IDAHO SPRINGS STRG RES

Structure dossier · WDID 0704398 · RESERVOIR · CHICAGO CREEK · DWR record

Where this page's figures come from

Generated 2026-08-27 20:40 by Hydrohistorian. Sources: DWR HydroBase snapshot HydroBase_CO_20260707 (history) + CDSS REST (current), USGS NWIS cross-checks. Engine v0.5.0 (4ab2507) — every figure regenerates from this named code version and data image.

Current administration

● In priority — no active call senior to this structure's rights affects its district (23 active call(s) checked).

Which of its rights get called out?

In the 5 past years whose flows most resemble this one (2025, 2024, 2018, 2020, 2016): this structure's most junior right was out of priority in 12 of the next 12 weeks at least once; its most senior right in 12. Its other 8 rights fall between those ends, each taken in priority order.

Week startingMost junior right out inMost senior right out in
2026-08-09 5 of 5 analog years 5 of 5
2026-08-16 5 of 5 analog years 5 of 5
2026-08-23 5 of 5 analog years 5 of 5
2026-08-30 5 of 5 analog years 5 of 5
2026-09-06 5 of 5 analog years 5 of 5
2026-09-13 5 of 5 analog years 5 of 5
2026-09-20 5 of 5 analog years 5 of 5
2026-09-27 5 of 5 analog years 5 of 5
How this outlook is built, and what it is not

Flows at CHICAGO CREEK BELOW IDAHO SPRINGS RESERVOIR around 2026-08-09 (the newest reading on file) sit at 99% of that gage's own median for this window. The 5 most similar past years with a complete administration record (1950–2026) supply the history; each week asks whether a call senior to a given right's admin number was in force that week of the analog year, using the same controlling-call-per-day computation as the Legal tab. Priority is per RIGHT: a structure with several decrees loses its most junior first, and the columns above are the two ends of its range. A frequency among named historical years, not a probability from a model, and not a forecast of what the division engineer will do. It says how often years whose flow resembled this one were under a call senior to this right in a given week. Snowpack, storage, and the actual administrative decisions of a given season are not modelled. Check the analog years listed: if they do not resemble this year to you, the outlook does not either.

Where it sits in line

Priority 1880-12-31 — 96th most senior of the 1815 structures with decreed rights in this water districtDWR's administrative subdivision of a river basin; the unit calls are usually stated in..

Under prior appropriationColorado's rule for sharing water: first in time, first in right. Age decides, not proximity or need., everything ahead of it in this line is satisfied in full before it receives any water. Immediately ahead: 0700700 (1880-09-20). Immediately behind: 0705325 (1881-01-29).

On CHICAGO CREEK at river mile 14.1, it is 1st of 2 down the reach. Nothing modelled upstream of it on this reach. Immediately downstream: CHICAGO CREEK DITCH.

Position on the modelled network, not a claim about whose water this is — a stream carries water from many rights at once, and diverted water returns to it.

Decreed rights (10)

Admin noDWR's numeric encoding of a water right's seniority. Smaller is more senior; the integer part counts days from 1849-12-31 to the date that ranks the right. AppropriatedWhen water was first put to beneficial use. It sets seniority unless a prior adjudication date is later. AdjudicatedWhen the water court confirmed the right. A use decreed in 1975 was not a decreed use in 1955, however old the appropriation is. AbsoluteA right actually put to use, as opposed to conditional -- a placeholder for a use not yet made. ConditionalA right reserving a place in line for a use not yet made; it must be diligently pursued or it lapses. UnitsUsesWhat the court said this water may be used for -- irrigation, municipal supply, augmentation and so on.Case
11323.01880-12-311914-10-09 1.5250.0 AMUNFIRDOM
13879.01887-12-311914-10-09 1.5250.0 AMUNFIRDOM
19357.01902-12-311914-10-09 1.5250.0 AMUNFIRDOM
20818.01906-12-311914-10-09 1.5250.0 AMUNFIRDOM
43829.206781906-08-131970-12-31 150.00.0 AMUNFIRDOM
48942.483491982-05-171984-12-31 0.01850.0 AIRRMUNCOMINDRECFISFIRDOMSTKWLD
48947.01984-01-051984-12-31 0.00.0 CIRRMUNCOMINDRECFIRDOMAUGPWRRCH
55670.02002-06-022002-12-31 0.00.0 CMUN
59896.02013-12-272013-12-31 0.00.0 CAUG
61330.02017-11-302017-12-31 0.00.0 CAUG

Recorded use (last 13 years on record)

In a median year this structure has a recorded diversion of 87 AF. Its most recent year on record, 2025, came in at 87 AF — 100% of that, and 6th lowest of the 11 years with a recorded volume.

This structure records both diversions and reservoir releases — they are separate water movements and are accounted separately below.

YearDiverted (AFA volume: one acre covered a foot deep, about 326,000 gallons -- roughly a suburban household's outdoor use for a year.)Compared with its own recordReleased (AF)Days recordedPeak (cfs)
1997 — no recorded volume 1 0 —
1998 — no recorded volume 2 0 —
2015 28 1st lowest of 11 · 32% of median 276 54 1.6
2016 165 10th lowest of 11 · 190% of median 195 179 1.5
2017 127 9th lowest of 11 · 146% of median 1,413 176 3.9
2018 79 5th lowest of 11 · 91% of median 36 274 2.1
2019 73 4th lowest of 11 · 84% of median 37 212 1.6
2020 91 7th lowest of 11 · 105% of median 653 311 2.7
2021 113 8th lowest of 11 · 130% of median 1,352 303 3.1
2022 178 11th lowest of 11 · 205% of median 27 318 9.7
2023 49 3rd lowest of 11 · 56% of median 23 304 1.8
2024 29 2nd lowest of 11 · 33% of median 2 61 1.7
2025 87 6th lowest of 11 · 100% of median 11 304 1.6

Advisory reading aid on public data — not an administrative or legal conclusion, not a title opinion, and not a substitute for DWR administration or an engineer's analysis. Methodology review status is disclosed at hydrohistorian's basin pages.