Cooper Lake Water Level Today

Also known as Jim Chapman Lake · Cooper (Chapman) Lake

Daily level, percent full and history for Cooper Lake, on the Sulphur River in Texas.

Updated · Source: Texas Water Development BoardTWDB

Water level

433.91ft

msl · Daily reading for Nov 7, 2026

  • 6.09 ftbelow full pool (440.0 ft)
  • 61.9%full
  • −0.04 ftin 24 h−0.20 ft in 7 days−1.11 ft in 30 days
432434436438440442432434436438440442432434436438440442
  • Full pool
  • 1 yr ago

Storage 160,145 of 258,723 acre-ft

Is Cooper Lake full?

No. Cooper Lake is 61.9% full, 6.09 ft below full pool. It is 2.59 ft lower than a year ago (436.50 ft on Nov 7, 2025).

Cooper Lake level history

View data table
DateLevel (ft)% full
Nov 7, 2026433.9161.9%
Nov 6, 2026433.9562.1%
Nov 5, 2026433.9962.3%
Nov 4, 2026434.0362.6%
Nov 3, 2026434.0762.8%
Nov 2, 2026434.0562.7%
Nov 1, 2026434.0962.9%
Oct 31, 2026434.1163.0%
Oct 30, 2026434.1463.2%
Oct 29, 2026434.1863.4%
Oct 28, 2026434.2163.6%
Oct 27, 2026434.2463.7%
Oct 26, 2026434.2863.9%
Oct 25, 2026434.3264.2%
Oct 24, 2026434.3664.4%
Oct 23, 2026434.4064.6%
Oct 22, 2026434.4464.8%
Oct 21, 2026434.4765.0%
Oct 20, 2026434.4965.1%
Oct 19, 2026434.5365.4%
Oct 18, 2026434.5865.6%
Oct 17, 2026434.6365.9%
Oct 16, 2026434.7166.4%
Oct 15, 2026434.7766.7%
Oct 14, 2026434.8066.9%
Oct 13, 2026434.8367.1%
Oct 12, 2026434.8767.3%
Oct 11, 2026434.9167.5%
Oct 10, 2026434.9467.7%
Oct 9, 2026434.9867.9%
Oct 8, 2026435.0268.2%
  • Cooper Lake level
  • Full pool 440.0 ft
  • Above full pool
Source: TWDB · Daily readings since 2000

Cooper Lake on Nov 7 in past years

Cooper Lake water level on Nov 7 in past years
YearLevel (ft)vs today% full
2026today433.91—
61.9%
2025436.50+2.59
77.0%
2024436.66+2.75
78.0%
2023438.75+4.84
91.5%
2022434.67+0.76
66.1%
2021437.91+4.00
86.1%
2020436.30+2.39
76.1%
2019438.24+4.33
88.2%
2018440.68+6.77
100%above full pool
2017438.63+4.72
90.8%
2016436.87+2.96
79.6%

Today’s level is the lowest for this date since 2014.

Lake facts

Full pool (conservation pool)
440.0 ft msl
Dead pool
415.50 ft msl
Conservation capacity
258,723 acre-ft
Surface area today
14,217 acres
Highest since 2000
448.51 ftMar 2, 2018
Lowest since 2000
422.02 ftDec 28, 2006
Data since
Oct 1, 2000
Dam
Cooper Damcompleted 1991
River
Sulphur River
Dam location
Delta County
Gauge location
33.3334, −95.6252

Dam, river and owner from the National Inventory of Dams (USACE). Records cover Oct 1, 2000 to today (daily averages).

Sulphur River chain

UpstreamSulphur RiverDownstream
  1. Wright Patman Lake224.74 ft100% full+4.14 ft vs full pool

Weather on the lake

  1. Tonight49°FLowN 0–5 mphMostly Cloudy
  2. Sunday72°FHighLow 45°FN 0–5 mphPartly Sunny
  3. Monday73°FHighLow 54°FCalmMostly Sunny
  4. Tuesday75°FHighLow 57°FSW 0–5 mphMostly Sunny
  5. Wednesday79°FHighLow 51°FWSW 5 mphMostly Sunny then Slight Chance Rain Showers
  6. Thursday73°FHighLow 43°FNNW 10–15 mphSunny
  7. Friday68°FHighLow 43°FNNW 5 mphSunny

Forecast: National Weather Service for the dam area (33.33, −95.63). Wind speeds are forecasts, not measurements.

Nearby lakes

Quick answers

What is the full pool level of Cooper Lake?
440.0 ft above mean sea level, the top of its conservation pool. Above it, the extra water is flood storage that is later released downstream through Cooper Dam.
How much does Cooper Lake need to be full?
Cooper Lake needs 6.09 ft more water to reach full pool (440.0 ft), or about 98,578 acre-ft of storage, as of Nov 7, 2026.
Is Cooper Lake rising or falling?
It is falling: −0.20 ft in the last 7 days and −0.04 ft in 24 hours, to 433.91 ft on Nov 7, 2026 (Texas Water Development Board).
When was Cooper Lake last full?
It was last at or above full pool (440.0 ft) on Jul 20, 2025. On Nov 7, 2026 it was 6.09 ft below.
What is the highest level in our data?
Cooper Lake reached 448.51 ft on Mar 2, 2018. The lowest was 422.02 ft on Dec 28, 2006 (TWDB data since 2000; older records are not in this data set).
How much has Cooper Lake changed in the last year?
In the last 12 months it ranged from 433.91 ft (Nov 7, 2026) to 438.55 ft (Jun 25, 2026), a swing of 4.64 ft.
How often is this page updated?
This page is updated every morning with the daily reading published by the Texas Water Development Board. The last reading is from Nov 7, 2026.

Where this data comes from

Daily reservoir data from the Texas Water Development Board (Cooper Lake on waterdatafortexas.org). Updated every morning. Weather from the National Weather Service. Dam details from the National Inventory of Dams.

Lake Levels Daily is an independent site, not affiliated with TWDB, LCRA, USACE, USGS, NOAA, TVA or any lake operator. Check official sources before making safety decisions.