Hydrohistorian
← My Water · Print / save as PDF
ISLAND LAKE
Structure dossier · WDID 0604236 · RESERVOIR · NORTH BOULDER CREEK · DWR record
Where this page's figures come from
Generated 2026-08-27 22:09 by Hydrohistorian. Sources: DWR HydroBase snapshot HydroBase_CO_20260707 (history) + CDSS REST (current), USGS NWIS cross-checks. Engine v0.5.0 (96d5528) — every figure regenerates from this named code version and data image.
Where it sits
Location as DWR records it. Faint dots are the neighbouring water; click any to open it.
Which of its rights are out of priority?
Not computable for this structure: no administrative call record for this basin.
Where it sits in line
Priority 1890-07-15 — 169th most senior of the 1867 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: SILVER LAKE DITCH (1888-02-28). Immediately behind: 0604219 (1891-04-01).
On NORTH BOULDER CREEK at river mile -13.3, it is 8th of 14 down the reach. Immediately upstream: GOOSE LAKE. Immediately downstream: SILVER LAKE.
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 (8)
| 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. | Units | UsesWhat the court said this water may be used for -- irrigation, municipal supply, augmentation and so on. | Case |
|---|---|---|---|---|---|---|---|
| 20188.14806 | 1890-07-15 | 1907-03-13 | 372.0 | 0.0 | A | MUNCOMINDFIRDOM | |
| 45290.3835 | 1954-12-31 | 1974-12-31 | 0.0 | 0.0 | C | MUN | |
| 52595.52594 | 1993-12-30 | 1994-12-31 | 0.0 | 0.0 | C | IRRMUNCOMINDFIRDOMAUG | |
| 52795.0 | 1994-07-19 | 1994-12-31 | 0.0 | 0.0 | C | IRRMUNCOMINDFIRDOMAUG | |
| 52958.0 | 1994-12-29 | 1994-12-31 | 0.0 | 0.0 | C | MUNALL | |
| 55141.0 | 2000-12-20 | 2000-12-31 | 0.0 | 0.0 | C | IRRMUNCOMINDRECFISFIRDOMAUGPWR | |
| 60963.0 | 2016-11-28 | 2016-12-31 | 0.0 | 0.0 | C | MUN | |
| 61357.0 | 2017-12-27 | 2017-12-31 | 0.0 | 0.0 | C | MUN |
Legal record & documents
13 decreed actions on record across
8 court cases:
16CW3160, 00CW0226, 94CW0285, 94CW0284, 03CW0440, W7852, 86CW0123, CA4842.
Every case, dated
| Case | Actions | Latest adjudication | Types |
|---|---|---|---|
16CW3160 | 2 | 2017-12-31 | S |
00CW0226 | 1 | 2000-12-31 | S |
94CW0285 | 1 | 1994-12-31 | S |
94CW0284 | 4 | 1994-12-31 | S |
03CW0440 | 1 | 1994-12-31 | S |
W7852 | 2 | 1974-12-31 | S |
86CW0123 | 1 | 1974-12-31 | S |
CA4842 | 1 | 1907-03-13 | S |
DWR's own records for this structure: net amounts · transactions & adjudication history · scanned decrees (search a case number there for the imaged document). On this site: the district's full legal picture →
Recorded use (last 14 years on record)
In a median year this structure has a recorded diversion of 328 AF. Its most recent year on record, 2024, came in at 109 AF — 33% of that, and 2nd lowest of the 13 years with a recorded volume.
This structure records both diversions and reservoir releases — they are separate water movements and are accounted separately below.
| Year | Diverted (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 record | Released (AF) | Days recorded | Peak (cfs) |
|---|---|---|---|---|---|
| 1993 | 331 | 8th lowest of 13 · 101% of median | — | 16 | 20.2 |
| 1994 | 333 | 9th lowest of 13 · 102% of median | — | 32 | 5.4 |
| 1995 | 333 | 9th lowest of 13 · 102% of median | — | 33 | 11.6 |
| 1997 | 30 | 1st lowest of 13 · 9% of median | — | 2 | 15.1 |
| 2000 | 340 | 13th lowest of 13 · 104% of median | — | 8 | 25.0 |
| 2003 | — | no recorded volume | 95 | 0 | — |
| 2004 | 333 | 9th lowest of 13 · 102% of median | — | 32 | 6.3 |
| 2005 | 125 | 3rd lowest of 13 · 38% of median | — | 22 | 3.0 |
| 2007 | 135 | 4th lowest of 13 · 41% of median | — | 11 | 8.0 |
| 2008 | 149 | 5th lowest of 13 · 45% of median | — | 6 | 15.0 |
| 2011 | 176 | 6th lowest of 13 · 54% of median | — | 32 | 3.0 |
| 2012 | 328 | 7th lowest of 13 · 100% of median | — | 57 | 9.5 |
| 2014 | 335 | 12th lowest of 13 · 102% of median | — | 31 | 7.3 |
| 2024 | 109 | 2nd lowest of 13 · 33% of median | — | 10 | 12.0 |
Trends for this structure
Recorded use shows no clear trend over its last 13 recorded years — which is itself worth knowing.
Its reference gage, SILVER LAKE OUTLET: no clear flow trend.
How good is our record of it?
Grade B (7/10 points) — the components below are the finding; the letter alone is not.
The rubric, component by component
| Check | State | Detail |
|---|---|---|
| identity | complete | name, type, and water source all on file |
| decreed rights | on file | 8 right(s), seniority decoded |
| diversion record | stale | 292 measured days, but newest is 806 day(s) before the data's end (target 450) |
| record continuity | sparse | 4% of the irrigation seasons in 1993-2024 carry measured days |
| published-record stability | stable | no upstream revisions recorded against this structure |
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.