Perfect World
Hydrology Metering

Caballo Dam · Rio Grande · NM

Caballo Reservoir

The re-regulating pool 25 miles below Elephant Butte that actually times the water's arrival in the valley.

Water surface elevation

4,133.8 ft

Bureau of Reclamation, daily · daily value, Aug 31

Water in storage

14,021 acre-feet

Bureau of Reclamation, daily · daily value, Aug 31

Share of capacity

4.1% full

against the project figure capacity figure (USBR Caballo Dam project data)

Below full pool

48.2 ft

full pool at 4,182.0 ft

This month in the record

lower than 75% of the 88 Septembers on record

monthly mean storage; record low 4,462 acre-feet (1956), record high 239,710 acre-feet (1987)

30-day trend

-19.4 af/day

storage, 2026-07-312026-08-30; over the year +32.7 af/day. Measured change, not a forecast.

Drought at the dam

D2 — Severe drought

US Drought Monitor at the dam's coordinates, released 2026-08-27; the feeding basin can differ.

full pool 4,182 ftcolumn continues below4,134

4.1% full

of capacity, by storage (project figure figure, USBR Caballo Dam project data). Sedimentation slowly shrinks real capacity.

The water line is elevation (USBR project datum); the percentage is storage ÷ capacity. They are different measures — a reservoir's volume is not linear in its depth, so the line's height in this column is not the percentage.

Snowpack in the feeding basin

Measured across the Rio Grande headwaters in Colorado and northern New Mexico.

Snow season

typically Oct 26 – May 27

0.1 in on the ground, 2026-09-01; median peak 17.3 in around Apr 17

Last winter's verdict

50% of median peak

water year 2026 — the snow that fed this year's pool

5 highest active SNOTEL stations in the basin (Elwood Pass, Rat Creek, Grayback, …), NRCS AWDB REST (SNOTEL), station set pinned 2026-08-31. Daily snow-water equivalent against the stations' own 30-year medians; off season the percent is withheld rather than divided by zero.

The last 120 days

Daily water-surface elevation in feet. The axis hugs the data — it does not start at zero. Source: committed snapshot (USBR RISE, retrieved 2026-08-31).

4132.34140.04147.6May 3Jul 2Aug 304133.8
See the numbers as a table
DateElevation (ft)
Aug 304133.82
Aug 294133.82
Aug 284133.84
Aug 274133.85
Aug 264133.88
Aug 254133.90
Aug 244133.92
Aug 234133.94
Aug 224133.98
Aug 214133.97
Aug 204134.03
Aug 194134.04
Aug 184134.03
Aug 174134.03
Aug 164134.05
Aug 154134.03
Aug 144134.06
Aug 134134.06
Aug 124134.06
Aug 114134.08
Aug 104134.09
Aug 94134.11
Aug 84134.11
Aug 74134.12
Aug 64134.13
Aug 54134.15
Aug 44134.19
Aug 34134.14
Aug 24134.13
Aug 14134.13

Most recent 30 days shown.

The whole record

Monthly mean elevation, Feb 1938 to Aug 2026. The axis spans the pools, not zero; elevations in USBR project datum. Months with fewer than 15 gaged days are dropped, and gaps in the record break the line. Source: USBR RISE, retrieved 2026-08-31.

monthly mean elevationpool reference lines
4,1124,1494,186Feb 1938May 1982Aug 2026full pool4,134
See the numbers as a table
MonthMean elevation (ft)Days gaged
Aug 20264134.030
Jul 20264135.931
Jun 20264139.530
May 20264141.731
Apr 20264134.630
Mar 20264134.831
Feb 20264134.928
Jan 20264134.731
Dec 20254134.431
Nov 20254134.230
Oct 20254134.231
Sep 20254132.430
Aug 20254128.031
Jul 20254139.231
Jun 20254141.529
May 20254142.131
Apr 20254136.330
Mar 20254136.531
Feb 20254136.528
Jan 20254136.331
Dec 20244136.031
Nov 20244135.730
Oct 20244135.631
Sep 20244134.930

Most recent 24 months shown; the full monthly series is in the page's API response.

Storage against capacity

Monthly mean storage in acre-feet, zero baseline. The dashed line is the project figure capacity figure (USBR Caballo Dam project data) — sedimentation slowly shrinks real capacity. Storage can legitimately rise past a conservation-pool line when the flood pool is in use.

monthly mean storagecapacity
0180,595361,190Feb 1938May 1982Aug 2026capacity14,530
See the numbers as a table
MonthMean storage (acre-feet)Days gaged
Aug 202614,53030
Jul 202618,48931
Jun 202627,59430
May 202633,99231
Apr 202615,76130
Mar 202616,16931
Feb 202616,24728
Jan 202615,80931
Dec 202515,29431
Nov 202514,88330
Oct 202514,96631
Sep 202512,14330
Aug 20255,94131
Jul 202526,36331
Jun 202533,79730
May 202535,15831
Apr 202519,27930
Mar 202519,73731
Feb 202519,75028
Jan 202519,31631
Dec 202418,67931
Nov 202418,05530
Oct 202417,68531
Sep 202416,40130

Most recent 24 months shown.

Where these numbers come from

Readings at Caballo Reservoir are the measuring agencies' own: each value above names its source (USGS gage, Bureau of Reclamation daily record, Army Corps project data, or this desk's committed copy) and its observation time in the reservoir's own time zone. The capacity figure is the project figure USBR Caballo Dam project data number; sedimentation slowly shrinks real capacity, so the vintage travels with the percent.