Lake Sumner water level — New Mexico

New Mexico · USACE · reading Aug 22, 2026, 1:15 PM (UTC+00:00)

Lake Sumner in New Mexico was last measured at 4,237.85 ft (datum NAVD88), as of Aug 22, 2026, 1:15 PM (UTC+00:00) (USACE CWMS Data). Over its recent trend window the level has been steady (+0.1 ft).

Current reading Lake Sumner · New Mexico
Pool elevation
4,237.85 ft

Datum NAVD88. (Why datum matters →)

% of conservation pool full
Not reported
Storage
4,781 acre-ft
Recent trend
→Steady

+0.1 ft over the trend window

Recent trend

Readings this station published between Jun 2, 2026 and Jun 7, 2026 — a 5-day window — downsampled for display.

4245.6ft4245.5ftJun 2 – Jun 7

Data: USGS Water Services (waterservices.usgs.gov) and USACE CWMS Data (cwms-data.usace.army.mil), retrieved 2026-08-31. Both public domain (a work of the U.S. Government, 17 U.S.C. §105).

Not for navigation or safety decisions (why →)

Source: USACE SPA/Sumner, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00). Official page for this lake →

About this gauge's record

USACE's continuous elevation record for this project begins in 1999 (2 tracked series for this project).

The dam behind Lake Sumner

Lake Sumner is held back by Sumner Dam (also recorded as Alamagordo;Sumner Lake) , an earthfill embankment, holding the pool back by sheer mass and an impervious core rather than by the strength of concrete , standing 164 ft high and running 3,084 ft along its crest , built across PECOS RIVER in De Baca County , near FORT SUMNER . It was completed in 1937 and modified in 1956S , and is owned by BUREAU OF RECLAMATION (a federal owner) , to a design credited to O.L. RICE.

Its recorded primary purpose is flood risk reduction — the pool is drawn down between storms so there is empty space waiting for the next flood, which is why this level can fall in dry weather and climb sharply after rain . It also serves flood risk reduction;irrigation.

Its spillway is ungated: once the pool reaches the crest, water leaves on its own and the operator cannot hold it back. The spillway opening is 135 ft wide. Its outlet works use tainter (radial)3.

NID classes it high hazard potential. That describes what a failure would cost downstream — loss of life would be expected — and says nothing about how likely a failure is, or what condition the dam is in.

At its normal pool the reservoir covers about 7,615 acres. NID records a maximum storage of 227,683 acre-ft against a normal storage of 63,690 acre-ft. Its maximum discharge capacity is 56,000 cubic feet per second.

Dam facts: National Inventory of Dams record NM00130 , filed by Bureau of Reclamation — U.S. Army Corps of Engineers, public domain. Water levels above come from USACE CWMS Data and are a separate source. (How this dam was matched to this gauge →)

How Lake Sumner compares nearby

3 of 6 nearby lakes with a current trend are also steady right now.

Nearby lakes

The six nearest published lakes by centroid distance (great-circle) — cross-state neighbors included.

Lakes nearest to Lake Sumner, with current level and distance.
Lake State Level Distance
Santa Rosa Lake NM 4,694.24 ft 55 km
Conchas Lake NM 4,180.59 ft 90 km
Ute Reservoir NM 3,784.41 ft 118 km
Two River Reservoir NM 3,977.02 ft 149 km
Diamond a Reservoir NM 3,957.00 ft 149 km
Two Rivers Dam NM 3,957.00 ft 151 km

Frequently asked questions

What is the current water level of Lake Sumner?
As of Aug 22, 2026, 1:15 PM (UTC+00:00), the pool elevation was 4,237.85 ft (datum NAVD88). See the trend chart above for the recent direction.
Is Lake Sumner full right now?
Its managing agency does not publish a %-of-conservation-pool-full figure for this lake, so we show the bare level rather than estimate one.
Where does this data come from?
From USACE SPA/Sumner, retrieved Aug 31, 2026, 8:24 AM (UTC+00:00).

More in New Mexico

See every lake tracked in New Mexico, or read the methodology behind these figures.