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Arkansas: Headwaters to Salida

Division 2 · Water District 11 · As of 2026-08-19 03:34 MDT

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Reconstruct conditions as of

Evolution of the network

Gage flow trend & changepoints

What counts as a trend here

Computed 2026-08-20 08:33 from 62 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 62 gages with enough record, 3 are trending down and 6 up, and 9 carry a detected shift. The clearest is ARKANSAS RIVER AT GRANITE, CO., +5.4 points of its long-term median per decade over 117 years (p<0.0001). The other 51 show no clear signal either way.

Gage	Trend	Change / decade points of median	Significance	Years	Changepoint
▸ LAKE FORK CREEK ABOVE TURQUOISE LKCTURCO	↓ decreasing	-225.7	p=0.000	33	~2014
▸ SOUTH ARKANSAS RIVER BELOW GARFIELD SOARGRCO	↑ increasing	+153.8	p=0.020	11	—
▸ LAKE FORK CREEK BELOW SUGAR LOAF DAM NEAR LEADVILLE LFCBSLCO	↓ decreasing	-73.1	p=0.000	57	~1986
▸ LAKE FORK ABOVE SUGAR LOAF RESERVOIR, CO. LFCASLCO	no clear trend	+21.4	p=0.159	22	~1960
▸ LAKE CREEK BELOW TWIN LAKES RESERVOIR LAKBTLCO	↑ increasing	+21.0	p=0.012	60	~1980
▸ CHARLES H. BOUSTEAD TUNNEL BOUTUNCO	↑ increasing	+20.2	p=0.002	55	~1991
▸ BUSK-IVANHOE TUNNEL BUSTUNCO	↓ decreasing	-7.5	p=0.044	64	~1986
▸ TWIN LAKES TUNNEL TWITUNCO	↑ increasing	+7.5	p=0.001	92	~2003
▸ SOUTH ARKANSAS RIVER NEAR SALIDA, CO. SOARSACO	↑ increasing	+7.1	p=0.049	31	—
▸ ARKANSAS RIVER AT GRANITE, CO. ARKGRNCO	↑ increasing	+5.4	p=0.000	117	~1964
▸ ARKANSAS RIVER NEAR NATHROP, CO ARKNATCO	no clear trend	-3.6	p=0.084	55	~1999

51 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. 42 gage(s) and 0 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)
1900s	1	0
1910s	8	0
1920s	4	0
1930s	4	0
1940s	4	0
1950s	14	1
1960s	17	0
1970s	25	110
1980s	22	110
1990s	26	170
2000s	28	188
2010s	36	212
2020s	41	109

Mass-balance (network closure) trend

Structure divrec-history backfill coverage as of the last check: 2% of 3197 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 (1950–2026)

Mass-balance kinks computed for every summer month back to 1950 (4327 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.

EF ARKANSAS R AT US HIGHWAY 24, NR LEADVILLE, CO.: reach shifted from -756 cfs to +81 cfs summer mean (more gaining, p=0.013, 37 yr) [sedimentary uplands: moderate groundwater connectivity -- gain/loss shifts can be real aquifer response; corroborate with nearby well records]
ARKANSAS RIVER AT BUENA VISTA, CO.: reach shifted from +959 cfs to +792 cfs summer mean (more losing, p=0.027, 23 yr) [mountain crystalline canyon: minimal groundwater storage -- large or shifting unaccounted losses here are more consistent with data/measurement issues or unmodeled plumbing than with aquifer exchange] [11 alluvial wells within 2 mi of the gage; pooled water table +1.3 ft (1971–2003, no_trend)]
ARKANSAS RIVER AT GRANITE, CO.: reach shifted from +700 cfs to +266 cfs summer mean (more losing, p=0.000, 77 yr) [mountain crystalline canyon: minimal groundwater storage -- large or shifting unaccounted losses here are more consistent with data/measurement issues or unmodeled plumbing than with aquifer exchange] [measurement-evolution caution: this shift co-moves with the growth of the gage/metering network (rho=-0.42) -- part of it may be unaccounted water becoming accounted, not hydrologic change] [2 alluvial wells within 2 mi of the gage; pooled water table -0.4 ft (1972–1994, no_trend)]
SOUTH ARKANSAS RIVER NEAR SALIDA, CO.: reach shifted from -47 cfs to -15 cfs summer mean (more gaining, p=0.010, 18 yr) [alluvial valley: real alluvial aquifer -- a decades-long shift toward losing is the classic signature of alluvial pumping and urbanization] [measurement-evolution caution: this shift co-moves with the growth of the gage/metering network (rho=0.62) -- part of it may be unaccounted water becoming accounted, not hydrologic change] [9 alluvial wells within 2 mi of the gage; pooled water table +1.3 ft (1990–2009, no_trend)]
ARKANSAS RIVER AT SALIDA, CO.: reach shifted from +1277 cfs to -54 cfs summer mean (more losing, p=0.000, 77 yr) [alluvial valley: real alluvial aquifer -- a decades-long shift toward losing is the classic signature of alluvial pumping and urbanization] [measurement-evolution caution: this shift co-moves with the growth of the gage/metering network (rho=-0.59) -- part of it may be unaccounted water becoming accounted, not hydrologic change] [19 alluvial wells within 2 mi of the gage; pooled water table +4.2 ft (1971–2025, decreasing)]
CLEAR CREEK ABOVE CLEAR CREEK RESERVOIR, CO.: reach shifted from -686 cfs to -426 cfs summer mean (more gaining, p=0.001, 75 yr) [mountain crystalline canyon: minimal groundwater storage -- large or shifting unaccounted losses here are more consistent with data/measurement issues or unmodeled plumbing than with aquifer exchange] [2 alluvial wells within 2 mi of the gage; pooled water table -0.4 ft (1972–1994, no_trend)]

Groundwater now has its own tab: 221 monitored well(s), water-table trends, stream corridors, and the advisory depletion screen.

Reservoirs now has its own tab: 9 reservoir(s), end-of-year storage back to 1949, click-to-chart histories.

Cross-gage pattern fingerprint

Over the 92-year window with full coverage (1935–2026), the dominant shared pattern across 3 gage(s) explains 61% of year-to-year variance (almost certainly a basin-wide climate/snowpack driver).

TWITUNCO doesn't move with that shared pattern -- a real, localized signal (a new diversion, land-use change, or a gage-specific data problem) worth a closer look, not necessarily noise.

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 45 day(s) old (target 7)
diversion record	stale	newest diversion record is 1024 day(s) old (DWR publishes ~1 year in arrears)
structure coverage	sparse	2% of schematic structures have data

Independent check: PASS — 100.0000% agreement across 133,957 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 — 99.82% day-level agreement with USGS's own published records for the same gages, across 29 co-listed station(s) and 281,373 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.

62 gage(s) / 719,555 daily values (1909-10-01–2026-07-06); 419 structure(s) with diversion records; 1489 with decreed rights. Methodology has not yet had independent expert review — treat every figure as an advisory screen, not an administrative or legal conclusion.

3,234 water-level measurements across 221 monitored well(s) — 142 alluvial, 0 bedrock — plus 3 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 23 well(s) with enough record for a trend test: 9 declining, 2 rising.

Fastest-declining wells	Setting	ft / decade	Span	p
▸ SC01108018AAA	unknown	-12.48	18 yr	0.0
▸ NA05000814DCB	alluvial	-4.89	24 yr	0.0001
▸ SC01507834CCD	alluvial	-2.32	36 yr	0.0
▸ SC01407830DAA	unknown	-2.24	54 yr	0.0
▸ NA05100833AAD	alluvial	-2.06	44 yr	0.0
▸ NA05000835AAD	alluvial	-1.89	54 yr	0.0
▸ NA05000733DAB	alluvial	-1.87	45 yr	0.0003
▸ SC00908032ACD	alluvial	-0.47	44 yr	0.0055

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.

ARKANSAS RIVER AT BUENA VISTA, CO.: 11 alluvial well(s) nearby; pooled water table +1.3 ft (1971–2003, no_trend, p=0.4573)

ARKANSAS RIVER AT GRANITE, CO.: 2 alluvial well(s) nearby; pooled water table -0.4 ft (1972–1994, no_trend, p=0.8267)

SOUTH ARKANSAS RIVER NEAR SALIDA, CO.: 9 alluvial well(s) nearby; pooled water table +1.3 ft (1990–2009, no_trend, p=0.8711). Glover screen: 0.3 cfs of nearby metered alluvial pumping → est. lagged depletion 0.2–0.3 cfs (uncalibrated T/S ranges; flagged for SPDSS calibration, AWAS cross-check, and expert review — DWR's AWAS is the authority).

ARKANSAS RIVER AT SALIDA, CO.: 19 alluvial well(s) nearby; pooled water table +4.2 ft (1971–2025, decreasing, p=0.0). Glover screen: 0.3 cfs of nearby metered alluvial pumping → est. lagged depletion 0.3–0.3 cfs (uncalibrated T/S ranges; flagged for SPDSS calibration, AWAS cross-check, and expert review — DWR's AWAS is the authority).

CLEAR CREEK ABOVE CLEAR CREEK RESERVOIR, CO.: 2 alluvial well(s) nearby; pooled water table -0.4 ft (1972–1994, no_trend, p=0.8267)

LAKE FORK CREEK BELOW SUGAR LOAF DAM NEAR LEADVILLE: 1 alluvial well(s) nearby

LAKE CREEK BELOW TWIN LAKES RESERVOIR: 1 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.

9 reservoir(s) with 17,935 storage measurement(s), 1949–2018. Basin storage as of 2018-04-30 (the record's own end — reservoir records publish ~annually): 103,958 AF across 2 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
▸ BEAR LAKE (CHAFFEE CTY) MIN LEVEL (1103927)	102,989	1979-10-31
▸ TURQUOISE RESERVOIR (1103500)	95,794	2018-01-23
▸ TWIN LAKES RESERVOIR (1103503)	80,503	1984-10-31
▸ CLEAR CREEK RESERVOIR (1103504)	8,164	2018-04-30
▸ NORTH FORK RESERVOIR (1103300)	583	2010-10-31
▸ O'HAVER RESERVOIR (1103921)	168	2010-09-30
▸ COTTONWOOD LAKE (1104005)	102	2010-10-31
▸ RAINBOW LAKE (M COTTONWD CRK) (1103535)	59	2010-10-31

Decreed rights on this network run from 1860-05-01 to 2022-11-03. 25 abandonment screens and 179 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: 1934 across 1489 structure(s); 119 structure(s) carry 0 court-case references. Advisory reading aids on public DWR data — not administrative or legal conclusions.

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).

BLOW DITCH - EMPIRE CREEK (1100729) (1890-12-01, 2.0 cfs decreed): last active 1912 — 109 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
IRON SILVER MINING CO-EVANS GULCH BRANCH (1100757) (1904-06-02, 0.3 cfs decreed): last active 1912 — 109 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
RESURRECTION DITCH (1100758) (1904-06-01, 3.3 cfs decreed): last active 1912 — 109 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
EGGLESTON DITCH (1100846) (1885-04-20, 1.0 cfs decreed): last active 1913 — 108 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
PINON CANON DITCH (1100847) (1886-09-01, 3.4 cfs decreed): last active 1913 — 108 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
ROCK CLIFF DITCH (1100852) (1890-01-30, 2.0 cfs decreed): last active 1913 — 108 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
LIPPARD DITCH (1100853) (1895-05-01, 2.0 cfs decreed): last active 1913 — 108 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
TOWN DITCH (1100854) (1895-05-01, 1.5 cfs decreed): last active 1913 — 108 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
SCANGA DITCH (1100856) (1896-07-01, 2.8 cfs decreed): last active 1913 — 108 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
WILLIAMS DITCH (1100876) (1877-04-30, 1.0 cfs decreed): last active 1913 — 108 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 (179 advisory flags)

Screened 260 of 1489 structures with rights (281 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.

TURQUOISE RESERVOIR (1103500): Observed p99 daily rate 804.3 cfs (max 1260.9) exceeds total decreed absolute 3.0 cfs across 12875 recorded day(s). Structure holds an Augmentation-use decree -- diversions above the direct-flow decree can be lawful under plan operations; interpret with care.
OTERO PUMP STATION (1100529): Observed p99 daily rate 180.5 cfs (max 180.7) exceeds total decreed absolute 1.7 cfs across 4079 recorded day(s). Structure holds an Augmentation-use decree -- diversions above the direct-flow decree can be lawful under plan operations; interpret with care.
SALIDA "OLD" GALLERY (1100882): Observed p99 daily rate 76.5 cfs (max 110.2) exceeds total decreed absolute 2.5 cfs across 3126 recorded day(s).
CHAMP DITCH (ARK) (1100517): Observed p99 daily rate 52.8 cfs (max 52.8) exceeds total decreed absolute 5.0 cfs across 10598 recorded day(s).
BOWEN DITCH (1100691): Observed p99 daily rate 50.0 cfs (max 55.5) exceeds total decreed absolute 44.5 cfs across 7630 recorded day(s). Structure holds an Augmentation-use decree -- diversions above the direct-flow decree can be lawful under plan operations; interpret with care.
BUSK-IVANHOE SYSTEM (1104612): Observed p99 daily rate 49.6 cfs (max 74.7) exceeds total decreed absolute 17.5 cfs across 13026 recorded day(s).
HELENA DITCH (1100535): Observed p99 daily rate 40.0 cfs (max 50.5) exceeds total decreed absolute 36.0 cfs across 16496 recorded day(s).
MCFARLAND DITCH (1100702): Observed p99 daily rate 40.0 cfs (max 40.0) exceeds total decreed absolute 0.4 cfs across 6452 recorded day(s).
STEVENS & LEITER WELL (1100759): Observed p99 daily rate 36.0 cfs (max 36.0) exceeds total decreed absolute 1.1 cfs across 4698 recorded day(s).
FISH DITCH (1100546): Observed p99 daily rate 25.0 cfs (max 25.0) exceeds total decreed absolute 0.2 cfs across 7432 recorded day(s).

Seniority (top structures by decreed rate)

Structure	Senior priority date	Rights	Decreed abs (cfs)	Conditional?
MT ELBERT CONDUIT (1101123)	1939-02-10	1	370.0	—
HALFMOON DIVERSION (1102057)	1881-05-07	4	150.0	—
D & C PIPELINE NO 3 (1100887)	1908-07-05	1	72.8	—
SETHMAN PIPELINE HDGT 1 (1100804)	1904-06-01	1	63.8	—
MISSOURI PARK DITCH (1100570)	1880-11-15	3	55.0	—
STARR DITCH (LOWER PT) (1100786)	1860-05-01	1	51.0	—
BOWEN DITCH (1100691)	1888-09-24	1	44.5	—
SUNNYSIDE PARK DITCH (1100539)	1884-01-03	3	39.2	—
HELENA DITCH (1100535)	1882-03-01	3	36.0	—
PIONEER DITCH (BROWNS) (1100632)	1866-05-17	3	31.0	—
RIVERSIDE-ALLEN DITCH (1100534)	1872-11-01	4	29.0	—
STEVENS & LEITER DITCH (1100751)	1873-09-01	1	27.6	—
WILLOWDALE DITCH (1100684)	1867-05-31	9	24.9	—
WOLF & NEERLAND DITCH (1100651)	1877-04-01	6	21.4	—
NEW SALIDA DITCH (1100536)	1882-05-01	1	20.0	—

No inventory or legal-document changes detected since the daily watch began.

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.

Stream	Gage	R-mile	Predicted (cfs)	Observed (cfs)	Δ (cfs)	Reach (mi)	Hypothesis
MAINSTEM	PONCHA CREEK AT PONCHA SPRINGS (PNCKPSCO)	321.8	253.9	2.0	-251.9	240.7	Unaccounted -251.9 cfs loss over 240.7 mi. No structure clearly responsible — possible ungaged diversion, channel seepage / phreatophyte loss, or evapotranspiration.
MAINSTEM	ARKANSAS RIVER NEAR NATHROP, CO (ARKNATCO)	63.8	0.0	208.0	+208.0	4.8	Unaccounted +208.0 cfs gain over 4.8 mi. No structure clearly responsible — possible ungaged return flow, baseflow from groundwater, or unmodeled tributary inflow.
MAINSTEM	COTTONWOOD CREEK NEAR BUENA VISTA (COCRBVCO)	48.3	147.7	3.3	-144.4	13.3	Unaccounted -144.4 cfs loss over 13.3 mi. No structure clearly responsible — possible ungaged diversion, channel seepage / phreatophyte loss, or evapotranspiration.
MAINSTEM	ARKANSAS RIVER BELOW GRANITE, CO (ARKBGNCO)	35.0	7.5	147.7	+140.2	0.9	Unaccounted +140.2 cfs gain over 0.9 mi. No structure clearly responsible — possible ungaged return flow, baseflow from groundwater, or unmodeled tributary inflow.
MAINSTEM	CLEAR CREEK ABOVE CLEAR CREEK RESERVOIR, CO. (CCACCRCO)	31.0	100.8	23.7	-77.1	1.1	Unaccounted -77.1 cfs loss over 1.1 mi. No structure clearly responsible — possible ungaged diversion, channel seepage / phreatophyte loss, or evapotranspiration.
MAINSTEM	ARKANSAS RIVER NEAR WELLSVILLE, CO. (ARKWELCO)	81.1	197.3	253.9	+56.6	5.6	Unaccounted +56.6 cfs gain over 5.6 mi. No structure clearly responsible — possible ungaged return flow, baseflow from groundwater, or unmodeled tributary inflow.
MAINSTEM	ARKANSAS RIVER AT GRANITE, CO. (ARKGRNCO)	29.9	46.8	100.8	+54.1	3.3	Unaccounted +54.1 cfs gain over 3.3 mi. No structure clearly responsible — possible ungaged return flow, baseflow from groundwater, or unmodeled tributary inflow.
MAINSTEM	ARKANSAS RIVER BELOW EMPIRE GULCH NEAR MALTA, CO (ARKEMPCO)	20.1	3.1	43.1	+40.0	7.7	Unaccounted +40.0 cfs gain over 7.7 mi. No structure clearly responsible — possible ungaged return flow, baseflow from groundwater, or unmodeled tributary inflow.
MAINSTEM	LARKSPUR DITCH AT MARSHALL PASS (LARDITCO)	59.0	17.7	0.0	-17.7	3.9	Unaccounted -17.7 cfs loss over 3.9 mi. No structure clearly responsible — possible ungaged diversion, channel seepage / phreatophyte loss, or evapotranspiration.
MAINSTEM	PINE CREEK AT MOUTH (PINMOUCO)	34.1	23.7	7.5	-16.2	3.1	Unaccounted -16.2 cfs loss over 3.1 mi. No structure clearly responsible — possible ungaged diversion, channel seepage / phreatophyte loss, or evapotranspiration.
MAINSTEM	LAKE CREEK BELOW TWIN LAKES RESERVOIR (LAKBTLCO)	26.6	32.4	46.8	+14.4	6.0	Unaccounted +14.4 cfs gain over 6.0 mi. No structure clearly responsible — possible ungaged return flow, baseflow from groundwater, or unmodeled tributary inflow.
MAINSTEM	CHALK CREEK AT NATHROP (CHCRNACO)	55.1	3.8	17.7	+13.9	1.4	Unaccounted +13.9 cfs gain over 1.4 mi. No structure clearly responsible — possible ungaged return flow, baseflow from groundwater, or unmodeled tributary inflow.
MAINSTEM	COTTONWOOD CREEK BELOW HOT SPRINGS (COCRHSCO)	359.4	9.2	22.9	+13.7	2.7	Unaccounted +13.7 cfs gain over 2.7 mi. No structure clearly responsible — possible ungaged return flow, baseflow from groundwater, or unmodeled tributary inflow.
MAINSTEM	ARKANSAS RIVER NEAR LEADVILLE, CO (ARKLEACO)	12.2	0.0	11.9	+11.9	12.2	Unaccounted +11.9 cfs gain over 12.2 mi. No structure clearly responsible — possible ungaged return flow, baseflow from groundwater, or unmodeled tributary inflow.
MAINSTEM	NORTH FORK SOUTH ARKANSAS RIVER (NFSOAKCO)	360.2	22.9	11.4	-11.5	0.8	Unaccounted -11.5 cfs loss over 0.8 mi. No structure clearly responsible — possible ungaged diversion, channel seepage / phreatophyte loss, or evapotranspiration.
MAINSTEM	PUEBLO WEST PIONEER (BROWN) AUGMENTATION STATION (PWPBASCO)	368.1	11.4	0.6	-10.8	7.9	Unaccounted -10.8 cfs loss over 7.9 mi. No structure clearly responsible — possible ungaged diversion, channel seepage / phreatophyte loss, or evapotranspiration.
MAINSTEM	CLEAR CREEK BELOW CLEAR CREEK RESERVOIR (CCBCCRCO)	20.6	43.1	32.4	-10.7	0.5	Unaccounted -10.7 cfs loss over 0.5 mi. No structure clearly responsible — possible ungaged diversion, channel seepage / phreatophyte loss, or evapotranspiration.
MAINSTEM	ARKANSAS RIVER AT SALIDA, CO. (ARKSALCO)	75.5	208.0	197.3	-10.7	11.7	Unaccounted -10.7 cfs loss over 11.7 mi. No structure clearly responsible — possible ungaged diversion, channel seepage / phreatophyte loss, or evapotranspiration.
MAINSTEM	SOUTH ARKANSAS RIVER BELOW GARFIELD (SOARGRCO)	356.7	0.2	9.2	+9.0	3.5	Unaccounted +9.0 cfs gain over 3.5 mi. No structure clearly responsible — possible ungaged return flow, baseflow from groundwater, or unmodeled tributary inflow.
MAINSTEM	LAKE FORK CREEK BELOW SUGAR LOAF DAM NEAR LEADVILLE (LFCBSLCO)	12.4	11.9	3.1	-8.8	0.2	Unaccounted -8.8 cfs loss over 0.2 mi. No structure clearly responsible — possible ungaged diversion, channel seepage / phreatophyte loss, or evapotranspiration.
MAINSTEM	EF ARKANSAS R AT US HIGHWAY 24, NR LEADVILLE, CO. (ARKEFOCO)	371.2	1.9	10.3	+8.3	2.6	Unaccounted +8.3 cfs gain over 2.6 mi. No structure clearly responsible — possible ungaged return flow, baseflow from groundwater, or unmodeled tributary inflow.
MAINSTEM	BROWNS CREEK ABOVE CONFLUENCE OF ARKANSAS (BCACOACO)	373.2	10.7	2.6	-8.1	1.1	Unaccounted -8.1 cfs loss over 1.1 mi. No structure clearly responsible — possible ungaged diversion, channel seepage / phreatophyte loss, or evapotranspiration.

Gage ⇅	Station ⇅	Avg cfs Aug 10–Aug 16 ⇅	% Hist Median ⇅	Rank ⇅	Δ1wk ⇅	Δ4wk ⇅	Yrs ⇅	Status ⇅
SOARGRCO	SOUTH ARKANSAS RIVER BELOW GARFIELD	9.2	42%	0	+0	+0	9.9	STALE
LKCTURCO	LAKE FORK CREEK ABOVE TURQUOISE	2.3	30%	0	+0	-0	29.1	SHORT_RECORD
ARKEMPCO	ARKANSAS RIVER BELOW EMPIRE GULCH NEAR MALTA, CO	43.1	36%	0	+7	-1	11.2	SHORT_RECORD
ARKBGNCO	ARKANSAS RIVER BELOW GRANITE, CO	147.7	32%	0	+46	+45	13.9	SHORT_RECORD
COCRHSCO	COTTONWOOD CREEK BELOW HOT SPRINGS	22.9	53%	0	+1	-1	12.3	SHORT_RECORD
PNCKPSCO	PONCHA CREEK AT PONCHA SPRINGS	2.0	33%	0	+1	-2	10.9	SHORT_RECORD
SOAKNBCO	SOUTH ARKANSAS ABOVE NEWBY BORING DITCH	8.9	54%	0	-5	-2	6.3	SHORT_RECORD
DD3AUGCO	DERRY DITCH NO 3 AUGMENTATION	0.0	0%	0	+0	+0	5.7	SHORT_RECORD
GYCROHCO	GRAY'S CREEK BELOW O'HAVER RESERVOIR	0.7	50%	6	+0	-0	13.2	SHORT_RECORD
NFSOAKCO	NORTH FORK SOUTH ARKANSAS RIVER	11.4	55%	7	+1	+2	10.2	SHORT_RECORD
PINMOUCO	PINE CREEK AT MOUTH	7.5	75%	19	+0	-0	7.3	SHORT_RECORD
PWWDASCO	PUEBLO WEST COMBINED AUGMENTATION STATION NEAR WILLOWDALE HEADGATE	3.8	59%	33	-0	+0	12.2	SHORT_RECORD
HRGTNDCO	HARRINGTON DITCH	1.9	0%	50	-0	-0	0.2	SHORT_RECORD
BCACOACO	BROWNS CREEK ABOVE CONFLUENCE OF ARKANSAS	2.6	145%	55	+1	+2	3.2	SHORT_RECORD
PWPBASCO	PUEBLO WEST PIONEER (BROWN) AUGMENTATION STATION	0.6	6689%	57	+1	+1	7.7	SHORT_RECORD
SOAKTECO	SOUTH ARKANSAS BELOW TENNASSE DITCH	10.7	117%	59	-5	-4	16.2	SHORT_RECORD
BLKRSOCO	BOSS LAKE RESERVOIR OUTLET	0.2	348%	100	+0	+0	12.1	SHORT_RECORD
BUSTUNCO	BUSK-IVANHOE TUNNEL	0.1	5%	0	-0	-0	69.5	OK
LAKBTLCO	LAKE CREEK BELOW TWIN LAKES RESERVOIR	46.8	20%	0	+20	+28	57.7	OK
LARDITCO	LARKSPUR DITCH AT MARSHALL PASS	0.0	0%	0	+0	+0	63.9	OK
LFCBSLCO	LAKE FORK CREEK BELOW SUGAR LOAF DAM NEAR LEADVILLE	3.1	20%	0	+0	-1	56.8	OK
HOMTUNCO	HOMESTAKE TUNNEL	0.0	0%	0	+0	+0	59.7	OK
ARKEFOCO	EF ARKANSAS R AT US HIGHWAY 24, NR LEADVILLE, CO.	10.3	30%	0	-0	+1	36.2	OK
ARKLEACO	ARKANSAS RIVER NEAR LEADVILLE, CO	11.9	24%	0	+1	+0	52.2	OK
HALMALCO	HALFMOON CREEK NEAR MALTA, CO	7.6	28%	0	+0	-0	79.9	OK
LAKATLCO	LAKE CREEK ABOVE TWIN LAKES RESERVOIR, CO.	26.0	26%	0	-2	-5	78.3	OK
ARKGRNCO	ARKANSAS RIVER AT GRANITE, CO.	100.8	23%	0	+33	+36	115.8	OK
CCACCRCO	CLEAR CREEK ABOVE CLEAR CREEK RESERVOIR, CO.	23.7	39%	0	-2	-0	80.1	OK
ARKNATCO	ARKANSAS RIVER NEAR NATHROP, CO	208.0	30%	0	+26	+32	39.2	OK
ARKSALCO	ARKANSAS RIVER AT SALIDA, CO.	197.3	28%	0	+13	+6	116.8	OK
ARKWELCO	ARKANSAS RIVER NEAR WELLSVILLE, CO.	253.9	35%	0	+33	+33	65.2	OK
COLDITCO	COLUMBINE DITCH NEAR FREMONT PASS, CO.	0.0	0%	0	+0	+0	77.3	OK
EWIDITCO	EWING DITCH AT TENNESSEE PASS, CO.	0.0	0%	0	+0	+0	73.2	OK
WURDITCO	WURTZ DITCH NEAR TENNESSEE PASS	0.0	0%	0	+0	+0	78.5	OK
WUREXTCO	WURTZ EXTENSION	0.0	0%	0	+0	+0	35.0	OK
BOUTUNCO	CHARLES H. BOUSTEAD TUNNEL	0.0	0%	0	-0	-3	54.8	OK
CCBCCRCO	CLEAR CREEK BELOW CLEAR CREEK RESERVOIR	32.4	46%	8	+4	+7	53.6	OK
CHCRNACO	CHALK CREEK AT NATHROP	17.7	43%	10	+3	+5	55.6	OK
COCRBVCO	COTTONWOOD CREEK NEAR BUENA VISTA	3.3	42%	27	-5	+2	51.6	OK
TWITUNCO	TWIN LAKES TUNNEL	6.4	24%	30	-0	-3	90.9	OK