← Basin groundwater

HIGGINS 78604-F

Monitored well · 150653 · Division 1 · Water District 8

Its well permit here · Well permit at DWR ↗

Source DWR administrative record · verify at DWR well record ↗ Source DWR administrative record · verify at DWR permit record ↗

Unclassified

No aquifer or designated-basin assignment — administrative world unknown, kept out of recharge math.

Water-level record

No water-level measurements are cached for this well. It is in the well inventory — permit, construction and aquifer below — but nobody has logged a level we hold.

Geophysical log

DWR holds a geophysical log for this well, run 2016-04-23 (gamma, resistivity, spontaneous_potential). DWR's log page.

Formation picks (DWR)

AquiferTop ftBase ftNet sand ft
ALLUVIAL-9 8
DAWSON8 943 348
DENVER965 17

Net sand is DWR's own reading of the log (its gLogThickness), not the gross interval.

Net sand per aquifer, from the gamma curve

Computed here from DWR's own digital log (LAS): linear gamma index, clean/shale lines at p10/p90 of the gamma over the interval, sand where Vsh < 0.4, beds under 1.0 ft merged. DWR’s own pick is beside it, never averaged with it.

AquiferInterval ftNet sand ftNet / grossDWR net sand ftDifference ft
ALLUVIAL-9–8 1 0.09
DAWSON8–943 511 0.55 348 +163

A gamma cutoff is a convention, not a measurement. Against DWR’s own picks on 50 wells this one correlates at r 0.86 with a median error near 30% and no bias (how it was scored).

Curves digitized from the scan

Hydrohistorian traced the scanned log automatically. 2 curves passed the confidence gate; 27 did not and are listed with the reason. Screening data: the scan stays the record.

CurveInterval ftCoverageVerdict Curves like this one scored
64" Normal Resistivity (Ohm-m) 4–1654 97% not used: ambiguous rows 28%; scale OCR confidence 0.62
64" Normal Resistivity (Ohm-m) 4–1654 4% not used: coverage 4%; ambiguous rows 21%; curve class not verified by the benchmark: 64" Normal Resistivity traced as thin
Natural Gamma (CPS) 4–1654 98% pass r 0.99 median, error 3.3% of scale, 3% below r 0.8 (n 89) LAS
Single-Point Resistance (Ohms) 4–1654 97% pass r 0.99 median, error 0.6% of scale, 6% below r 0.8 (n 49) LAS
Spontaneous Potential (mV) 4–1654 97% not used: SP: the printed scale is a span with an unknown offset, and the benchmark could not verify the shape (median r 0.28 after offset removal)
CPS (CPS) 10–169 100% not used: ambiguous rows 20%; curve name not recognized: 'CPS'
Ohms (Ohms) 10–169 35% not used: coverage 35%; curve name not recognized: 'Ohms'
mV (mV) 10–169 77% not used: curve name not recognized: 'mV'
CPS (CPS) 180–389 100% not used: ambiguous rows 18%; curve name not recognized: 'CPS'
Ohms (Ohms) 180–389 42% not used: curve name not recognized: 'Ohms'
mV (mV) 180–389 91% not used: curve name not recognized: 'mV'
CPS (CPS) 400–609 100% not used: ambiguous rows 26%; curve name not recognized: 'CPS'
Ohms (Ohms) 400–609 47% not used: curve name not recognized: 'Ohms'
mV (mV) 400–609 81% not used: curve name not recognized: 'mV'
CPS (CPS) 620–829 100% not used: ambiguous rows 29%; curve name not recognized: 'CPS'
Ohms (Ohms) 620–829 38% not used: coverage 38%; curve name not recognized: 'Ohms'
mV (mV) 620–829 73% not used: curve name not recognized: 'mV'
CPS (CPS) 840–1049 100% not used: ambiguous rows 29%; curve name not recognized: 'CPS'
Ohms (Ohms) 840–1049 49% not used: ambiguous rows 36%; curve name not recognized: 'Ohms'
mV (mV) 840–1049 80% not used: curve name not recognized: 'mV'
CPS (CPS) 1060–1269 100% not used: ambiguous rows 28%; curve name not recognized: 'CPS'
Ohms (Ohms) 1060–1269 42% not used: ambiguous rows 7%; curve name not recognized: 'Ohms'
mV (mV) 1060–1269 79% not used: curve name not recognized: 'mV'
CPS (CPS) 1280–1489 100% not used: ambiguous rows 22%; curve name not recognized: 'CPS'
Ohms (Ohms) 1280–1489 42% not used: curve name not recognized: 'Ohms'
mV (mV) 1280–1489 84% not used: curve name not recognized: 'mV'
CPS (CPS) 1500–1654 92% not used: ambiguous rows 29%; curve name not recognized: 'CPS'
Ohms (Ohms) 1500–1654 48% not used: ambiguous rows 14%; curve name not recognized: 'Ohms'
mV (mV) 1500–1654 75% not used: curve name not recognized: 'mV'

"Curves like this one" is the benchmark row for this curve's class: curves of the same name traced the same way, scored against DWR's own digital log of the same run. r is correlation (the print's own smoothing allowed for); error is mean absolute error as a share of the track's printed range; "below r 0.8" is the share of passing curves in the class that still disagreed with DWR's log, which this curve's own numbers cannot rule out.

The LAS files and every verdict are in the statewide groundwater release (/data, table gw_digitized); the MCP server's gw_digitized_curves and gw_net_sand work from them. How well the tracer does was measured against DWR's own digital logs.

The well itself

Total depth1640.0 ft
Perforated interval960.0–1640.0 ft
Ground elevation7280.0 ft
Permit78604
Location39.13000, -104.74000
What this page is not

Monitoring records are irregular: measurements cluster where somebody chose to look, so a trend describes this well's record, not the aquifer as a whole. Levels are DWR's published measurements, unedited. A trend here is not a prediction, and it is not a determination about anyone's water right.