Holter Dam is a hydroelectric straight gravity dam on the Missouri River about 45 miles (72 km) northeast of Helena, Montana, in the United States.[3] The dam, which was built between 1908 and 1918, is 1,364 feet (416 m) long and 124 feet (38 m) high.[1][3] The reservoir formed by the dam, Holter Lake (also known as Holter Reservoir) is 25 miles (40 km) long and has a storage capacity of 243,000 acre feet (300,000,000 m3) of water when full.[4] The dam is a "run-of-the-river" dam because it can generate electricity without needing to store additional water supplies behind the dam
Holter Reservoir
Photo courtesy of Crystal Ash
Special Notices & Closures
Fishing Report for the week of 06/09/2025
Rainbow fishing has been productive during the early morning hours throughout most of the reservoir while trolling various flashers and spinners tipped with crawler pieces. A few rainbows are being picked up while fishing from shore at Departure Point with plain crawlers or Powerbait. Walleye fishing has been great around weed beds on the lower end of the reservoir while trolling bottom bouncers with crawler harnesses in 15 to 25 feet of water. A few northern pike are being caught while casting larger spoons around weed beds. Good numbers of perch are being caught in the same areas as the walleyes while trolling bottom bouncers or casting smaller jigs around weed beds.
Special Notices & Closures
Fishing Report for the week of 06/16/2025
Rainbow fishing has been great from Split Rock to the Dam and across from Cottonwood Creek while trolling 40 feet deep with downriggers and various flashers tipped with spinners and crawler pieces or soft plastics. An occasional kokanee is being picked up with the same equipment. Shore anglers are finding a few rainbows from the Gates of the Mountains Road and at Departure Point with plain crawlers or Powerbait. Walleye and perch fishing has been great on the lower end of the reservoir while pitching jigs and crawlers or leeches around weed beds in 10 to 25 feet of water. A few northern pike are being caught while casting swim baits or larger spoons around weed beds.
| Size: | 3666.94 acres |
| Elevation: | 3598.16 ft |
| Status of the Fishery: | Holter Reservoir is a popular year-round fishery for rainbow trout, walleye and yellow perch. In addition, kokanee salmon can be targeted primarily in deeper water near the dam. |
| Township/Range/Section: | 14N 3W 27 |
| Latitude/Longitude: | 46.93494 -111.96336 |
| FWP Region: | Region 4 |
| County: | |
| Fishing District: | Central |
Click on rows to select them for use in other tabs.
| Waterbody | Section | Field Form Type | Date | Purpose | Species |
|---|
To see this data, first select one or more rows from the Collection Info tab.
For Comparative analysis all Length Units are millimeters : all Weights are grams
| Species | Count | Avg | StdDev | Min | Max | AvgWgt | StdDevWgt | MinWeight | S/L | Sects | Surveys | Waterbody |
|---|
To see this data, first select one or more rows from the Collection Info tab.
For Comparative analysis all Length Units are millimeters : all Weights are grams
| Waterbody | Section | Species | Count | AveLength | StdDevLength | MinLength | MaxLength | AveWeight | StdDevWeight | MinWeight | MaxWeight |
|---|
To see this data, first select one or more rows from the Collection Info tab.
For Comparative analysis all Length Units are millimeters : all Weights are grams
| Waterbody | Year | Section | Species | Count | AveLength | StdDevLength | MinLength | MaxLength | AveWeight | StdDevWeight | MinWeight | MaxWeight |
|---|
To see this data, first select one or more rows from the Collection Info tab.
This is a preview, all fields will be visible by selecting a download option. For Comparative analysis all Length Units are millimeters : all Weights are grams.
| Year | Species Abbrv | Length | Weight | M/C | Count | Sex | Mort | Hook Scar | Disease | Scales | Otolith | Fin Clip | Tag | Comment | Genetics | Age | Stomach | Intercept | Slope | Gear | Equipment | Trip | Date | Pass/Run | Water | Section | Lat/Down | Lon/Down | Lat/Up | Lon/Up | Agency | Start Depth | End Depth |
|---|
View the latest Montana Fishing Regulations.
No Gauging Stations found.
This waterbody has a fish consumption advisory. Please see the link for guidelines.
Fish Consumption Guidelines (PDF)
