Access & Logistics

Current Conditions

Flow Rate Flow Rate
Wading:150–400 cfs
Floating:Not floatable
Current flow affects each method differently—see condition ratings.
187 cfs
Trend Trend
🔴Dropping Fast - ≤ -30%
🟠Dropping - -10% to -30%
🔘Stable - -10% to +10%
🔵Rising - +10% to +30%
🔴Rising Fast - > +30%
-16%

Flow data from USGS, USBR .

Hatch Guide for Ruby River - Alder

Gear Recommendations

ROD 5wt
LEADER 9-12ft , 4X-5X taper
TIPPET 4X-6X
INDICATOR Yarn, NZ style, or dry-dropper
RIG Indicator nymph (2-fly)
Fish: 10-14 inches avg, trophy to 18+

⚠️ REGULATIONS

Ruby River, downstream from Ruby Dam to the Beaverhead/Big Hole confluence at Twin Bridges — regulations vary by reach (2026 MT regulations): the channel just below Ruby Dam (dam to its confluence with the outlet channel, including the outlet channel) is closed year-round. Downstream from Ruby Dam: catch-and-release for rainbow trout. Ruby Dam to Alder Bridge (Ruby Island FAS): catch-and-release for brown trout; open April 1 through Sept. 30. Alder Bridge to the mouth: brown trout — 1 daily and in possession, must be less than 18 inches. Valid Montana fishing license required. See https://fwp.mt.gov/fish/regulations.

View official Montana regulations →

*Verify current regulations before fishing. Rules may change.

Map Ruby River - Alder

Nearby Rivers to Fly Fishing Ruby River – Alder

Fish Species

Fly Fishing Ruby River - Alder

The Ruby River near Alder offers excellent small stream fly fishing in one of Montana's most accessible and productive freestone fisheries, flowing through open ranchland and agricultural areas before joining the Beaverhead River. This section is characterized by fast-moving pocketwater, boulder gardens, and deep pools that create diverse fishing opportunities throughout the season. The combination of excellent water quality, abundant wild trout, and good access makes this a popular destination for both local and visiting anglers seeking a classic Montana small stream experience.

The Alder section flows through relatively flat terrain, creating a mix of fast riffles, deep runs, classic freestone pools, and extensive pocketwater. The river bottom consists of cobble, boulders, and gravel, providing excellent habitat for both trout and aquatic insects. The gradient is moderate to steep in places, creating excellent holding water with fast seams and deep pools. The banks are lined with willows, cottonwoods, and agricultural fields, providing essential cover and shade. The water clarity is typically excellent, with cold, highly oxygenated water that supports healthy trout populations. This is a small freestone stream that is ideal for wade fishing.

This section supports healthy populations of wild brown trout and rainbow trout, with fish typically ranging from 10 to 14 inches. The brown trout are particularly aggressive and opportunistic, often responding well to attractor patterns and terrestrials. Rainbow trout are protected by catch-and-release regulations downstream from Ruby Dam. Trophy fish exceeding 18 inches are possible, with fish over 20 inches occasionally caught. The section has a special regulation for brown trout: 1 daily and in possession, must be less than 18 inches. Mountain whitefish are also abundant and provide consistent action.

Hatch activity is good throughout the season, beginning after spring runoff subsides, typically in late May or early June. The section benefits from excellent mayfly and caddis hatches during summer, with various patterns producing exciting dry fly action. Blue-winged Olives emerge in spring and fall, PMDs appear in mid-summer, and various caddis species provide excellent evening fishing. Terrestrial patterns become extremely effective from mid-summer through early fall, with hoppers, ants, and beetles producing excellent results when fished tight to the banks. Nymphing remains productive year-round, with various mayfly, caddis, and stonefly patterns being effective.

Optimal wading flows for the Alder section range from 80 to 300 CFS, with flows above 400 CFS becoming challenging for safe wading. Typical flows vary dramatically by season, with spring runoff peaks and lower flows in fall/winter. The river is ideal for wade fishing, with good access along local roads. Access is good along local roads, with numerous public access points, fishing access sites, and pullouts throughout the section. The town of Alder provides limited services, with additional services available in Dillon and Twin Bridges. The nearest major commercial airport is Bozeman Yellowstone International (BZN), approximately 90-120 minutes away.

The Ruby River near Alder offers excellent small stream fly fishing opportunities in one of Montana's most accessible freestone fisheries. Its combination of healthy wild trout populations, diverse water types, and good access makes it an ideal destination for anglers seeking a classic Montana small stream experience. The section's reputation for consistent fishing and excellent hatches makes it a popular choice for both local and visiting anglers.