Mackenzie Reservoir: 11.7% full as of 2026-07-17

The elevation-storage rating curve used to produce the storage hydrograph is made of two segments: (1) the segment up to the conservation pool top (below the red line) is based on measured data, and (2) the segment in the flood pool (above the red line) is an extrapolation from the first segment and shouldn't be relied upon for flood storage information.

Historical Data

Date Percent Full Mean Water Level
(ft)
Reservoir Storage
(acre-ft)
Conservation Storage
(acre-ft)
Conservation Capacity
(acre-ft)
Surface Area
(acres)
Today 2026-07-17 11.7 3,020.24 5,441 5,441 46,450 246
Yesterday 2026-07-16 11.7 3,020.26 5,446 5,446 46,450 247
2 days ago 2026-07-15 11.7 3,020.29 5,452 5,452 46,450 247
1 week ago 2026-07-10 11.8 3,020.36 5,467 5,467 46,450 248
1 month ago 2026-06-17 12.0 3,020.85 5,571 5,571 46,450 250
3 months ago 2026-04-17 12.1 3,021.14 5,637 5,637 46,450 252
6 months ago 2026-01-17 12.6 3,021.98 5,846 5,846 46,450 258
1 year ago 2025-07-17 13.8 3,024.42 6,429 6,429 46,450 275
*

Percent Full is based on Conservation Storage and Conservation Capacity and doesn't account for storage in flood pool.

**

   Values above, including today's are averaged conditions. For near real-time instantaneous water level, see table below or the interactive map viewer.

Most Recent Instantaneous Water Level

Date/time Water Level
(ft)
Conservation Pool Elevation
(ft)
Height Above Conservation Pool
(ft)
Most recent 2026-07-17 10:30 3,020.25 3,100.00 -79.75
1 hour prior 2026-07-17 09:30 3,020.25 3,100.00 -79.75
2 hours prior 2026-07-17 08:30 3,020.24 3,100.00 -79.76
6 hours prior 2026-07-17 04:30 3,020.24 3,100.00 -79.76
12 hours prior 2026-07-16 22:30 3,020.25 3,100.00 -79.75
24 hours prior 2026-07-16 10:30 3,020.27 3,100.00 -79.73
48 hours prior 2026-07-15 10:30 3,020.30 3,100.00 -79.70
*

Data is provisional and subject to revision.

Additional Information

Impoundment date 1974-01-01
Vertical datum NGVD29
Service spillway crest elevation 3,100.00 ft above NGVD29
Emergency spillway crest elevation 3,110.00 ft above NGVD29
Top of dam elevation 3,126.00 ft above NGVD29
Conservation pool elevation 3,100.00 ft above NGVD29
Data download (CSV) period of record, last one year, last 30 days

Elevation-Area-Capacity Curves

1974-10-01 (source: TWDB)
Data Source USGS:07298100
USGS Monitoring Location USGS:07298100

Lake Location