South Platte Cheesman to Denver Gage

Division 1 · Water District 8 · As of 2026-08-27 01:50 MDT

Full analysis

⚠ This district is administered as part of the deployed South Platte product, whose modeled mainstem currently runs Denver gage → Greeley (the WD2 reach). The schematic and mass balance shown here are that combined product — this district's own upstream reach is not yet independently modeled. Calls, stations, and rights data ARE district-specific.

Reconstruct conditions as of

Evolution of the network

This year, in context

In the weeks around 2026-08-12 (the newest reading on file), flows at the 33 ranked gages are running at a median 24% of their own long-term norm for this window — 28 below a typical year, 5 at or above. Driest relative to its record: FOUBERCO, ranking 1st lowest of 6 years.

How this comparison is made

Each gage's mean flow over the 3 days either side of 2026-08-12, compared with the same window in every year of its own record — so a gage is only ever measured against itself, and gages with no record in the window are counted out rather than guessed.

Gage flow trend & changepoints

What counts as a trend here

Computed 2026-08-27 20:43 from 268 gage(s) with cached period-of-record data. Mann-Kendall (trend) and Pettitt (changepoint) both require at least 8 years spanning at least 10 years of record. A gage below that reports no signal — which is not the same as “no change.”

Of the 268 gages with enough record, 17 are trending down and 16 up, and 25 carry a detected shift. The clearest is PLAGEOCO, +13.8 points of its long-term median per decade over 96 years (p<0.0001). The other 233 show no clear signal either way.

Gage	Trend	Change / decade points of median	Significance	Years	Changepoint
▸ CHEBELCO	↑ increasing	+518.6	p=0.000	72	~1982
▸ ⚠️ CHEMELCO	↓ decreasing	-465.4	p=0.005	30	~1950
▸ LOWER LATHAM AUGMENTATION BYPASS LLABYPCO	↓ decreasing	-255.1	p=0.006	17	~2016
▸ UNION DITCH AUGMENTATION RETURN UAUGRTCO	↓ decreasing	-133.7	p=0.034	12	~2018
▸ CHEROKEE POWER PLANT RETURN TO SOUTH PLATTE RIVER CHERTNCO	↓ decreasing	-87.7	p=0.001	13	—
▸ ⚠️ FIRST CR BEL BUCKLEY RD, AT ROCKY MTN ARSENAL, CO FIRBUCCO	↑ increasing	+86.2	p=0.000	34	~2012
▸ SECTION NO 3 DITCH SECDITCO	↑ increasing	+84.1	p=0.036	17	—
▸ WESTERN MUTUAL DITCH AKA HEWES COOK WESDITCO	↓ decreasing	-79.7	p=0.050	30	~2010
▸ PLULOUCO	↑ increasing	+73.8	p=0.000	49	~1981
▸ SOUTH PLATTE R AT 64TH AVE. COMMERCE CITY, CO. PLASIXCO	↓ decreasing	-56.1	p=0.001	44	~2000
▸ FT. SAINT VRAIN POWER PLANT RETURN TO ST. VRAIN CREEK SVPPRTCO	↓ decreasing	-56.0	p=0.020	11	—
▸ UVALDA INTERCEPT BL 56TH AV AT ROCKY MTN ARS, CO RMAUVACO	↑ increasing	+41.5	p=0.042	19	—
▸ ROBTUNCO	↑ increasing	+37.6	p=0.001	62	~1988
▸ MEADOW ISLAND #2 AND BEEMAN COMBINED MDWDITCO	↓ decreasing	-35.4	p=0.006	17	~2017
▸ PLATTEVILLE DITCH DIVERSION PLADITCO	↓ decreasing	-26.0	p=0.006	17	—
▸ BIGDHICO	↓ decreasing	-25.7	p=0.037	22	—
▸ NORGENCO	↑ increasing	+25.5	p=0.000	62	~1963
▸ CHERRYCO	↑ increasing	+21.3	p=0.016	34	—
▸ ⚠️ CHEDENCO	↑ increasing	+19.8	p=0.000	71	~1982
▸ SAND CREEK AT MOUTH NR COMMERCE CITY,CO SANCOMCO	↓ decreasing	-19.3	p=0.002	33	~2009
▸ PLAENGCO	↓ decreasing	-17.9	p=0.011	43	—
▸ PLAANTCO	↓ decreasing	-16.1	p=0.010	50	~2002
▸ PLABAICO	↑ increasing	+14.7	p=0.041	31	—
▸ TARJEFCO	↓ decreasing	-14.4	p=0.020	11	~1917
▸ PLAGEOCO	↑ increasing	+13.8	p=0.000	96	~1983
▸ FULTON DITCH AT HEADGATE NEAR THORNTON FULDITCO	no clear trend	-13.6	p=0.093	28	~2012
▸ PLAHARCO	↑ increasing	+13.2	p=0.000	87	~1983
▸ PLASPICO	↓ decreasing	-12.3	p=0.017	43	~2000
▸ BURLINGTON-WELLINGTON CANAL BURCANCO	↓ decreasing	-11.3	p=0.005	40	~2011
▸ SOUTH PLATTE RIVER AT HENDERSON, CO PLAHENCO	↑ increasing	+8.5	p=0.000	100	~1968
▸ PLACHECO	↑ increasing	+8.4	p=0.000	101	~1981
▸ SOUTH PLATTE RIVER AT FORT LUPTON, CO. PLALUPCO	↑ increasing	+7.9	p=0.000	91	~1968
▸ ⚠️ NORSOPCO	no clear trend	+5.1	p=0.092	72	~1964
▸ PLASPLCO	↑ increasing	+4.7	p=0.000	127	~1968
▸ PLAWATCO	↓ decreasing	-3.2	p=0.043	100	—

⚠️ 6 gages flagged: their records may have quietly shifted against their neighbours, so treat their trends with caution.

How drift is detected

Every gage's annual flows are compared against each neighbour's as a double-mass curve (Searcy & Hardison, USGS WSP 1541-B); a Pettitt step test looks for a break in the ratio. A gage is flagged only when the breaks AGREE across its references, and a break against an already-suspect gage is never counted against a healthy one. A double-mass break means the ratio between two gages changed, not that either gage is faulty: a new diversion, a reservoir, or an import changes that ratio exactly as a rating shift does. Screening aid for expert review, never a measurement verdict.

233 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. 198 gage(s) and 689 structure(s) report in 2026, but structure reporting only reached half its modern level around ~1973. 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 †.

Decade	Gages with data (median yr)	Structures reporting (median yr)
1890s	2	0
1900s	2	0
1910s	7	0
1920s	8	0
1930s	12	0
1940s	17	0
1950s	20	174
1960s	21	82
1970s	22	368
1980s	32	358
1990s	62	338
2000s	72	307
2010s	104	494
2020s	195	689

Mass-balance (network closure) trend

Structure divrec-history backfill coverage as of the last check: 18% of 1468 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 (1950–2025)

Mass-balance kinks computed for every summer month back to 1950 (1323 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.

BIG DRY CREEK AT MOUTH NEAR FORT LUPTON: reach shifted from -624 cfs to -12 cfs summer mean (more gaining, p=0.026, 34 yr) [sedimentary plains/foothills: moderate groundwater connectivity -- gain/loss shifts can be real aquifer response; corroborate with nearby well records] [121 alluvial wells within 2 mi of the gage; pooled water table +0.0 ft (1966–2025, no_trend)]
SOUTH PLATTE RIVER AT FORT LUPTON, CO.: reach shifted from +86 cfs to +539 cfs summer mean (more gaining, p=0.000, 70 yr) [sedimentary plains/foothills: moderate groundwater connectivity -- gain/loss shifts can be real aquifer response; corroborate with nearby well records] [measurement-evolution caution: this shift co-moves with the growth of the gage/metering network (rho=0.6) -- part of it may be unaccounted water becoming accounted, not hydrologic change] [76 alluvial wells within 2 mi of the gage; pooled water table +1.1 ft (1929–2025, no_trend)]
FIRST CR BEL BUCKLEY RD, AT ROCKY MTN ARSENAL, CO: reach shifted from -30 cfs to -16 cfs summer mean (more gaining, p=0.049, 14 yr) [sedimentary plains/foothills: moderate groundwater connectivity -- gain/loss shifts can be real aquifer response; corroborate with nearby well records] [measurement-evolution caution: this shift co-moves with the growth of the gage/metering network (rho=0.53) -- part of it may be unaccounted water becoming accounted, not hydrologic change]

Groundwater now has its own tab: 8961 monitored well(s), water-table trends, stream corridors, and the advisory depletion screen.

Reservoirs now has its own tab: 284 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.

Data provenance & quality

Where these numbers come from and how far they can be trusted. Grade D (2/6 points) — the components below are the finding; the letter alone is not. Sources: DWR HydroBase snapshot HydroBase_CO_20260707 (imported 2026-08-19) for history, plus the CDSS REST API for current conditions.

Check	State	What was measured
gage freshness	stale	newest gage reading is 16 day(s) old (target 7)
diversion record	stale	newest diversion record is 666 day(s) old (DWR publishes ~1 year in arrears)
structure coverage	sparse	18% of schematic structures have data

Independent check: PASS — 100.0000% agreement across 53,853 stored values re-checked against DWR's authoritative record (HydroBase_CO_20260707), over 20 structures. 0 disagreement(s) beyond a 0.01 cfs tolerance. Checked 2026-08-19; a rotating sample covers the whole basin across successive runs, and the structures this report cites are checked every time.

Federal cross-check: PASS — 95.69% day-level agreement with USGS's own published records for the same gages, across 76 co-listed station(s) and 693,915 overlapping days (within max(2%, 0.5 cfs) daily). Pre-1950 records at some gages carry known between-agency day-stamp and transcription differences — scored at each year's best ±1-day alignment; residual disagreement is real historical divergence, flagged for review.

268 gage(s) / 1,581,428 daily values (1895-07-01–2026-08-12); 1752 structure(s) with diversion records; 21881 with decreed rights. Methodology has not yet had independent expert review — treat every figure as an advisory screen, not an administrative or legal conclusion.

176,163 water-level measurements across 8961 monitored well(s) — 3556 alluvial, 2848 bedrock — plus 170 administered well(s) reporting metered pumping.

What is being counted

Observation wells and pumping wells are different populations and are never conflated: water levels come from monitored observation wells, and metered pumping comes from administered wells reporting through diversion records. Click any well to chart its own record.

Well map

3D aquifer x-ray

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

How the surfaces are built, and what they are not

Alluvial water table on top, Denver Basin members (Dawson, Denver, Arapahoe, Laramie–Fox Hills) stacked beneath where measured, interpolated from measured water levels. Units are never mixed; a surface exists only inside its own unit's well coverage, with no extrapolation; thin epochs are suppressed and say why. Vertical scale is exaggerated for readability and z is head elevation in feet. These are measured heads, not a calibrated groundwater model.

Water-table trends

Of 390 well(s) with enough record for a trend test: 174 declining, 57 rising.

Fastest-declining wells	Setting	ft / decade	Span	p
▸ CASTLE PINES A-1	bedrock	-307.81	28 yr	0.0
▸ DB-106 CPNMD A-2	bedrock	-266.68	32 yr	0.0
▸ DB-106 CPNMD A-3	bedrock	-258.69	32 yr	0.0
▸ DB-113 DEN TECH CNTR, SOUTH	bedrock	-256.67	31 yr	0.0
▸ JORDAN WELL	bedrock	-255.88	21 yr	0.0375
▸ DB-118 CASTLE ROCK WELL 14	bedrock	-253.52	35 yr	0.0
▸ SC00606624ADA1	unknown	-251.12	22 yr	0.0
▸ DB-113 DEN TECH CNTR, NORTH	bedrock	-235.24	31 yr	0.0

Stream corridors — the surface connection

Where a reach's gain or loss has shifted, the wells within two miles of its anchoring gage and what their water table did over the same era.

How the corridor is assembled

For each reach whose gain/loss has shifted (Trends tab): the wells within 2 miles of its anchoring gage, their pooled water-table history over the same era, and an advisory Glover screen of lagged stream depletion from nearby metered pumping. v1 proximity = distance to the reach's anchoring gage; segment-based reach join is a flagged upgrade.

BIG DRY CREEK AT MOUTH NEAR FORT LUPTON: 121 alluvial well(s) nearby; pooled water table +0.0 ft (1966–2025, no_trend, p=0.9685). Glover screen: 0.1 cfs of nearby metered alluvial pumping → est. lagged depletion 0.1–0.1 cfs (uncalibrated T/S ranges; flagged for SPDSS calibration, AWAS cross-check, and expert review — DWR's AWAS is the authority).

SOUTH PLATTE RIVER AT FORT LUPTON, CO.: 76 alluvial well(s) nearby; pooled water table +1.1 ft (1929–2025, no_trend, p=0.126). Glover screen: 3.2 cfs of nearby metered alluvial pumping → est. lagged depletion 2.8–3.1 cfs (uncalibrated T/S ranges; flagged for SPDSS calibration, AWAS cross-check, and expert review — DWR's AWAS is the authority).

FIRST CR BEL BUCKLEY RD, AT ROCKY MTN ARSENAL, CO: 62 alluvial well(s) nearby

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.

284 reservoir(s) with 254,263 storage measurement(s), 1950–2025. Basin storage as of 2024-10-31 (the record's own end — reservoir records publish ~annually): 419,331 AF across 85 reservoir(s).

Why storage matters to the flow network

Storage change is real water the mass balance must credit — a losing reach beside a filling reservoir isn't losing water, it's banking it.

Reservoir map — how full is each vessel?

What “full” is measured against

Bubble size is proportional to a reservoir's record-high storage. Fill is its last recorded storage as a share of its surveyed capacity (USACE National Inventory of Dams) where a confident NID match exists — the tooltip names the matched dam — and as a share of its own record high otherwise. A wrong capacity would be worse than an honest record high, so only confident joins upgrade.

A dashed teal ring marks reservoirs reporting live DWR telemetry: their fill reflects yesterday's storage, is drawn as a dotted tail on charts, and is treated as provisional until the next verified HydroBase snapshot supersedes it.

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 reservoir to chart its full storage history.

Reservoir	Last recorded storage (AF)	As of
▸ ELEVEN MILE RES (2303965)	99,933	2024-10-31
▸ CHEESMAN RES (8003550)	70,058	2024-10-31
▸ STANDLEY RES (0203903)	35,226	2024-10-31
▸ CHATFIELD RESERVOIR (0803514)	33,272	2024-10-31
▸ SPINNEY MTN RESERVOIR (2304013)	30,953	2024-10-31
▸ AURORA RES (0203379)	23,062	2024-10-31
▸ ANTERO RES (2303904)	17,671	2024-10-31
▸ 0803601	16,977	1958-06-01

Decreed rights on this network run from 1859-03-01 to 2024-11-18. Of the 20 structures with a yield estimate, the median one’s senior right was in priority 46% of a median irrigation season and 26% in a dry one. 25 abandonment screens and 295 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: 28304 across 21881 structure(s); 1172 structure(s) carry 1919 court-case references. Advisory reading aids on public DWR data — not administrative or legal conclusions.

Is the river getting harder to divert from?

Over 2012–2025, none of the three measures of administration (days under call, calls set, seniority of the controlling call) shows a significant trend — the river is being administered about as it was.

The three measures, year by year

One row per whole calendar year inside the call record's coverage (14 years); partly-covered years are omitted rather than reported as quiet. Trend is Mann-Kendall with the same significance gate as every other trend on this site. Counted from DWR's published call record, which begins in the early 2000s: earlier years are absent, not quiet. A rise in the number of calls set can also reflect how finely an administrator records one episode, which is why days under call -- insensitive to that -- is the component to read first. Advisory summary of the public record, not an administrative finding.

Year	Days under call	Calls set	Controlling priority (median)
2014	309	220	1873-06-30
2015	330	159	1870-06-01
2016	366	246	1869-06-01
2017	365	334	1878-09-06
2018	365	392	1873-05-01
2019	365	315	1881-02-01
2020	366	297	1867-04-15
2021	349	243	1862-11-01
2022	365	309	1867-04-15
2023	331	274	1869-04-01
2024	366	248	1878-09-18
2025	365	390	1876-05-10

What the water is for — decade by decade

Of the water this district's structures diverted, the share whose decree includes municipal supply moved from 73% in the 1970s to 71% in the 2020s.

The decades, and how the attribution works

Every structure's recorded diversions, attributed to what its water was decreed FOR in that year. Colorado decrees are usually multi-use (“IRR MUN COM IND…”), so these are shares of water whose decree includes a use — non-exclusive, and they do not sum to 100%. A right that adds municipal use in 1988 counts toward it only after. Decades before this basin's modern reporting era are flagged: their records are thinner, not their rivers drier. Shares of recorded diverted volume, not of water rights or of acreage. A structure's water is attributed only to uses decreed by that year, so a later municipal decree cannot reach back and recolour earlier diversions. Families overlap -- a ditch decreed for irrigation and municipal supply counts in both -- so shares can sum past 100%. Volume the record cannot attribute is reported separately, never distributed.

Decade	Recorded AF	Structures	Includes municipal	Unattributed
1900s †	30	1	0%	0%
1910s †	3,142	1	100%	0%
1940s †	12,702	2	100%	0%
1950s †	4,931,345	241	71%	14%
1960s †	5,749,139	209	77%	23%
1970s	8,510,965	675	73%	16%
1980s	10,661,264	608	72%	7%
1990s	11,616,300	404	71%	6%
2000s	12,256,193	422	78%	11%
2010s	14,578,179	868	70%	22%
2020s	12,000,396	813	71%	22%

Why diversions stopped — call-based explanations

Sustained diversion stops matched to senior administrative calls.

TCVS-01 (0200525) DWR↗ stopped 2025-10-02 (5+ days) — call at INDEPENDENT HIGHLINE DITCH [heuristic-strong]
TCVS-01 (0200525) DWR↗ stopped 2025-06-13 (50+ days) — call at NEW CACHE LA POUDRE CO DITCH [heuristic-strong]
MILLIKEN RESERVOIR PUMP NO 1 (0200582) DWR↗ stopped 2024-11-30 (36+ days) — call at NORTH STERLING CANAL [heuristic-strong, district-confirmed]
MILLIKEN RESERVOIR PUMP NO 1 (0200582) DWR↗ stopped 2024-08-31 (16+ days) — call at STERLING IRR CO DITCH 1 [heuristic-strong, district-confirmed]
TCVS-01 (0200525) DWR↗ stopped 2024-08-17 (26+ days) — call at WESTERN MUTUAL DITCH [heuristic-strong, district-confirmed]
TCVS-01 (0200525) DWR↗ stopped 2024-03-09 (6+ days) — call at BIJOU CANAL [heuristic-strong, district-confirmed]
WESTERN SEEP DITCH (0200537) DWR↗ stopped 2023-10-15 (16+ days) — call at JACKSON LAKE INLET DITCH curtailing 100% of its decreed rate [heuristic-strong, district-confirmed]

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.

Structure	Senior priority	Senior right: median / dry yr	Junior right: median / dry yr
BURLINGTON D RIVER HEADGATE (0200802) DWR↗	1861-06-29	72.5% / 38.3%	0.0% / 0.0%
EVANS NO 2 DITCH (0200817) DWR↗	1871-10-05	34.5% / 19.6%	0.0% / 0.0%
UNION DITCH (0200828) DWR↗	1873-09-26	31.6% / 15.0%	0.0% / 0.0%
FULTON DITCH (0200808) DWR↗	1863-03-15	52.5% / 29.9%	0.0% / 0.0%
0801004 DWR↗	1861-08-30	72.5% / 38.3%	0.0% / 0.0%
2300693 DWR↗	1994-12-21	0.0% / 0.0%	0.0% / 0.0%
0801002 DWR↗	1860-12-28	91.8% / 72.0%	4.9% / 0.0%
0801017 DWR↗	1860-12-28	91.8% / 72.0%	0.0% / 0.0%
LOWER LATHAM DITCH (0200834) DWR↗	1869-05-12	35.2% / 21.5%	0.0% / 0.0%
0801016 DWR↗	1863-03-15	52.5% / 29.9%	11.4% / 0.0%
0200895 DWR↗	1970-05-13	0.0% / 0.0%	0.0% / 0.0%
BURLINGTON DITCH 2ND (0200865) DWR↗	1886-11-15	24.1% / 0.9%	24.1% / 0.9%

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 ~1973 — idleness that begins before then may be unreported use, not nonuse (flagged † below).

0801129 DWR↗ (1870-03-15, 1.0 cfs decreed): last active 1951 — 74 years idle † predates modern reporting era — last recorded activity predates this basin's modern reporting era (~1973) -- early absence of record is weak evidence of nonuse
2300988 DWR↗ (1878-08-01, 1.0 cfs decreed): last active 1951 — 74 years idle † predates modern reporting era — last recorded activity predates this basin's modern reporting era (~1973) -- early absence of record is weak evidence of nonuse
2300981 DWR↗ (1882-05-01, 10.0 cfs decreed): last active 1958 — 67 years idle † predates modern reporting era — last recorded activity predates this basin's modern reporting era (~1973) -- early absence of record is weak evidence of nonuse
2300543 DWR↗ (1876-12-31, 0.2 cfs decreed): last active 1962 — 63 years idle † predates modern reporting era — last recorded activity predates this basin's modern reporting era (~1973) -- early absence of record is weak evidence of nonuse
0200902 DWR↗ (1976-08-03, 100.0 cfs decreed): last active 1964 — 61 years idle † predates modern reporting era — last recorded activity predates this basin's modern reporting era (~1973) -- early absence of record is weak evidence of nonuse
0801462 DWR↗ (1861-08-30, 0.5 cfs decreed): last active 1968 — 57 years idle † predates modern reporting era — last recorded activity predates this basin's modern reporting era (~1973) -- early absence of record is weak evidence of nonuse
0200870 DWR↗ (1883-09-15, 13.0 cfs decreed): last active 1970 — 55 years idle † predates modern reporting era — last recorded activity predates this basin's modern reporting era (~1973) -- early absence of record is weak evidence of nonuse
2301504 DWR↗ (1983-07-31, 0.0 cfs decreed): last active 1970 — 55 years idle † predates modern reporting era — last recorded activity predates this basin's modern reporting era (~1973) -- early absence of record is weak evidence of nonuse
2301589 DWR↗ (1932-06-21, 0.1 cfs decreed): last active 1970 — 55 years idle † predates modern reporting era — last recorded activity predates this basin's modern reporting era (~1973) -- early absence of record is weak evidence of nonuse
2301639 DWR↗ (1961-09-02, 0.1 cfs decreed): last active 1970 — 55 years idle † predates modern reporting era — last recorded activity predates this basin's modern reporting era (~1973) -- early absence of record is weak evidence of nonuse

Compliance screens (295 advisory flags)

Screened 552 of 21881 structures with rights (762 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.

LORENZ TRUST 4-R12939 (0207026) DWR↗: Observed p99 daily rate 123904.7 cfs (max 123904.7) exceeds total decreed absolute 4.3 cfs across 12 recorded day(s).
0802922 DWR↗: Observed p99 daily rate 338.8 cfs (max 475.5) exceeds total decreed absolute 5.0 cfs across 5146 recorded day(s).
MILTON RES (0203876) DWR↗: Observed p99 daily rate 256.0 cfs (max 602.1) exceeds total decreed absolute 50.0 cfs across 34963 recorded day(s).
2303904 DWR↗: Observed p99 daily rate 215.0 cfs (max 462.0) exceeds total decreed absolute 6.0 cfs across 11185 recorded day(s).
0200902 DWR↗: Observed p99 daily rate 141.0 cfs (max 141.0) exceeds total decreed absolute 100.0 cfs across 36 recorded day(s).
2303962 DWR↗: Observed p99 daily rate 110.5 cfs (max 261.5) exceeds total decreed absolute 0.5 cfs across 40688 recorded day(s).
WHIPPLE DITCH (0200871) DWR↗: Observed p99 daily rate 94.6 cfs (max 143.0) exceeds total decreed absolute 6.0 cfs across 10045 recorded day(s).
SECTION NO 3 DITCH (0200830) DWR↗: Observed p99 daily rate 58.0 cfs (max 141.0) exceeds total decreed absolute 57.7 cfs across 33792 recorded day(s).
2300694 DWR↗: Observed p99 daily rate 50.0 cfs (max 50.0) exceeds total decreed absolute 35.4 cfs across 2574 recorded day(s).
EAST NERES CANAL (0200919) DWR↗: Observed p99 daily rate 49.6 cfs (max 185.9) exceeds total decreed absolute 25.0 cfs across 13610 recorded day(s).

Seniority (top structures by decreed rate)

Structure	Senior priority date	Rights	Decreed abs (cfs)	Decreed abs (AF)	Conditional?
BURLINGTON D RIVER HEADGATE (0200802) DWR↗	1861-06-29	52	5216.8	10000	yes
EVANS NO 2 DITCH (0200817) DWR↗	1871-10-05	17	1008.1	6565	yes
UNION DITCH (0200828) DWR↗	1873-09-26	11	744.3	620	yes
FULTON DITCH (0200808) DWR↗	1863-03-15	30	719.2	0	yes
0801004 DWR↗	1861-08-30	13	628.3	0	—
2300693 DWR↗	1994-12-21	1	600.0	0	—
0801002 DWR↗	1860-12-28	27	439.8	0	—
0801017 DWR↗	1860-12-28	25	413.0	0	yes
LOWER LATHAM DITCH (0200834) DWR↗	1869-05-12	7	329.6	0	yes
0801016 DWR↗	1863-03-15	3	300.0	0	—
0200895 DWR↗	1970-05-13	1	290.0	0	—
BURLINGTON DITCH 2ND (0200865) DWR↗	1886-11-15	1	250.0	0	—
BURLINGTON DITCH 3RD (0200866) DWR↗	1887-09-15	1	250.0	0	—
WESTERN MUTUAL DITCH (0200825) DWR↗	1866-05-05	8	242.3	0	yes
0801001 DWR↗	1863-12-30	18	230.0	474	yes

Recent inventory & legal-document changes

2026-08-26 — call set: LOWER PLATTE BEAVER D (39357)
2026-08-26 — call set: OGILVY DITCH (39359)
2026-08-26 — call released: 39331
2026-08-26 — call released: 39335
2026-08-26 — call released: 39333
2026-08-26 — call set: SOUTH FLAT DITCH (39348)
2026-08-26 — call set: HARRIMAN DITCH (39347)
2026-08-26 — call released: 39287

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.

What this does and doesn't model. Seniority arithmetic only: every right junior to the call is treated as curtailed. It does not model reach applicability — structures downstream of the calling point are not administered by it — and it applies no futile-call judgment. Read it as “who is junior to this date, and by how much,” not as a prediction of what the Division Engineer would actually order.

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.

Or enter an administration number directly

Administration number

DWR administration numbers encode appropriation and adjudication dates; lower is more senior.

Gage	Station	Avg cfs Aug 17–Aug 23	% Hist Median	Rank	Δ1wk	Δ4wk	Yrs	Status
FIRBUCCO	FIRST CR BEL BUCKLEY RD, AT ROCKY MTN ARSENAL, CO	3.6	361%	100	-3	+3	34.2	OK
BIGWESCO	BIG DRY CREEK AT WESTMINSTER, COLO	0.5	2%	0	-0	-2	37.7	OK
PLASIXCO	SOUTH PLATTE R AT 64TH AVE. COMMERCE CITY, CO.	100.3	49%	22	-130	+30	44.3	OK
PLAHENCO	SOUTH PLATTE RIVER AT HENDERSON, CO	242.9	67%	26	-151	+88	100.1	OK
PLALUPCO	SOUTH PLATTE RIVER AT FORT LUPTON, CO.	177.7	55%	16	-61	+97	89.3	OK
SANCOMCO	SAND CREEK AT MOUTH NR COMMERCE CITY,CO	39.2	82%	40	-6	+32	33.3	OK
BIGDAFCO	BIG DRY CREEK AT MOUTH NEAR FORT LUPTON	15.3	47%	0	+2	-0	34.6	OK
EVANS2CO	EVANS #2 DITCH	33.4	28%	0	-14	+33	33.5	OK
WESDITCO	WESTERN MUTUAL DITCH AKA HEWES COOK	66.9	75%	22	+27	+51	29.9	SHORT_RECORD
METSEWCO	METRO SEWER EFFLUENT AT DENVER	179.0	99%	3	-1	+8	5.2	SHORT_RECORD
BURCANCO	BURLINGTON-WELLINGTON CANAL	30.9	54%	0	-13	+7	37.3	OK
FULDITCO	FULTON DITCH AT HEADGATE NEAR THORNTON	80.8	98%	42	-2	-8	27.4	SHORT_RECORD
FRMDITCO	FARMERS INDEPENDENT DITCH	62.3	97%	21	-3	+5	18.6	SHORT_RECORD
SECDITCO	SECTION NO 3 DITCH	24.9	107%	54	-8	-8	17.8	SHORT_RECORD
SHLINLCO	SAND HILL LAKE (INLET)	0.0	0%	0	-0	+0	18.3	SHORT_RECORD
SHLOUTCO	SAND HILL LAKE (OUTLET)	0.0	0%	0	-3	+0	18.1	SHORT_RECORD
BRTDITCO	BRANTNER DITCH	39.8	105%	56	-1	+3	17.8	SHORT_RECORD
BRGDITCO	BRIGHTON DITCH	18.7	84%	27	-1	-2	17.8	SHORT_RECORD
LPBEASCO	LUPTON BOTTOM DITCH EAST AUG RET	4.9	99%	49	-0	-0	17.7	SHORT_RECORD
LPBWESCO	LUPTON BOTTOM DITCH WEST AUG RET	1.7	77%	17	+0	-0	17.8	SHORT_RECORD
MDWDITCO	MEADOW ISLAND #2 AND BEEMAN COMBINED	48.2	103%	67	+31	+37	17.3	SHORT_RECORD
SHLLMOCO	SAND HILL LAKE LM OUTLET	0.0	0%	0	+0	-0	17.8	SHORT_RECORD
LLADIVCO	LOWER LATHAM DITCH	106.5	60%	0	+7	+27	17.3	SHORT_RECORD
MEDIS1CO	MEADOW ISLAND NO 1 DITCH	20.1	92%	0	+12	+9	16.7	SHORT_RECORD
PLADITCO	PLATTEVILLE DITCH DIVERSION	54.2	100%	47	+4	+7	17.4	SHORT_RECORD
LLABYPCO	LOWER LATHAM AUGMENTATION BYPASS	0.0	0%	0	+0	+0	16.0	SHORT_RECORD
UNION2CO	UNION DITCH NEAR MILLIKEN	74.4	72%	0	+9	+15	17.4	SHORT_RECORD
NGLNLBCO	NORTHGLENN LUPTON BOTTOM AUG RETURN	0.5	18%	0	+0	-0	5.8	SHORT_RECORD
PLARTNCO	PLATTEVILLE DITCH CENTRAL AUG RT	1.5	68%	0	-0	+0	6.4	SHORT_RECORD
CENTLBCO	CCWCD LUPTON BOTTOMS 14.5 AUG RTN	3.8	59%	0	+0	-0	8.0	SHORT_RECORD
CENFULCO	CCWCD FULTON DITCH AUG RTN	1.4	50%	0	+0	+0	8.1	SHORT_RECORD
CHERTNCO	CHEROKEE POWER PLANT RETURN TO SOUTH PLATTE RIVER	0.0	0%	4	-0	+0	13.5	SHORT_RECORD
GDRDITCO	GARDENER DITCH TO CHEROKEE POWER PLANT	0.0	0%	0	+0	+0	13.4	SHORT_RECORD
DWRDECCO	DENVER WATER REUSE DELIVERY TO CHEROKEE POWER PLANT	4.1	0%	68	-0	-2	13.5	SHORT_RECORD
SPPUMPCO	SOUTH PLATTE PUMP STATION DELIVERY TO CHEROKEE POWER PLANT	0.0	0%	0	+0	+0	13.5	SHORT_RECORD
SANABDCO	SAND CREEK ABOVE BURLINGTON DITCH NEAR COMMERCE CITY, CO	49.6	371%	100	-26	+42	10.6	SHORT_RECORD
UAUGRTCO	UNION DITCH AUGMENTATION RETURN	1.5	56%	28	+1	+1	11.8	SHORT_RECORD
SVPPRTCO	FT. SAINT VRAIN POWER PLANT RETURN TO ST. VRAIN CREEK	1.8	107%	58	-0	+1	11.6	SHORT_RECORD
JAYTOMCO	JAY THOMAS DITCH	0.0	0%	0	+0	+0	11.5	SHORT_RECORD
BNSVPPCO	BEEMAN DITCH DELIVERY TO FORT ST. VRAIN POWER PLANT	6.5	68%	13	+6	+5	11.6	SHORT_RECORD