Compare 1 documented access option before you commit to a shoreline or launch.
View access →Montana lake guide
Harpers Lake Fishing
Harpers Lake is a compact western Montana trout lake with a 28-foot maximum depth. Its small size favors deliberate coverage of shoreline drop-offs and deeper central water; verify the current public access route and parking situation before towing or carrying a craft.
LocationPowell County, Montana
Primary targetsRainbow Trout
Best seasonSpring to early summer
Lake size14 acres
Max depth28 feet
Access1 documented option
Guide reviewed
Start here
Plan Harpers Lake in 60 seconds
Make the trip decisions first. Use the deeper lake science, surveys, stocking history, and source material below when you want more detail.
Start with the documented species list, then open a species guide for seasonal behavior and practical tactics.
Choose a fish →Use verified depth information to identify basins, breaks, points, channels, and other structure before you fish.
View depth information →Wind, rain, temperature, and changing access can alter the plan quickly. Check current conditions before leaving.
Check conditions →Lake details
Depth, size & key facts
Max depth28 feet
Elevation3,998 feet
Public launches1
Summer cautionWarm water
Lake depth map
Depth contours may take a little time to load. Sorry for the inconvenience.
Contour line20 ft Visible depth label
Source: Montana Fish, Wildlife & Parks. Historical survey data may not reflect current water levels or underwater hazards. Informational only; not for navigation.
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Trip conditions
Current conditions
Loading the local forecast. Check access and official notices before leaving.
TodayLoading
WindLoading
GustsLoading
Rain chanceLoading
Four day outlook
Tools
Today's Lure Pick
Open Tools for species-specific lure guidance.
Official depth chart
Official static bathymetry
Interactive contours available
Harpers Lake official depth chart
Open the official depth publication to inspect the lake chart. This static survey complements interactive contours when available and should not be used as a navigation chart.
Fishery record
Documented fish species
These species come from the lake record. Open a species guide for identification, seasonal behavior, and practical tactics without confusing general species guidance with a lake-specific survey result.
Stocking information
Harpers Lake Fish Stocking
Recent stocking information summarized from Montana Fish, Wildlife & Parks. Dates and quantities can change. Always verify current fishing rules with the official agency before fishing.
Official stocking history
Five-year summary · 2022–2026
View agency record Fish stocked17,542
Stocking events87
Years stocked5
Species stocked2
Species in this period: Rainbow Trout, Westslope Cutthroat Trout
Most recent stockings
| Date | Species | Quantity | Size | Details |
|---|---|---|---|---|
| Jun 19, 2026 | Rainbow Trout | 520 | 10.8 in avg length | Jocko River Trout Hatchery · Montana FWP Fish Stocking Records |
| Jun 9, 2026 | Rainbow Trout | 660 | 10.4 in avg length | Jocko River Trout Hatchery · Montana FWP Fish Stocking Records |
Source: Montana Fish, Wildlife & Parks Last checked: Sep 5, 2026 11:06am
Fishery intelligence
Official fishery evidence
Agency survey records and measured fishery data, distilled for trip planning.
7
verified signals
Research & surveys
Agency-backed record
Use the evidence
Turn records into a fishing plan
- Compare survey evidence with the seasonal guide.
- Use the map to connect depth, access, and structure.
- Confirm current rules and access before your trip.
Angler interpretation
How the fishery changes through the seasons
This is the practical layer: use it alongside the documented species, depth, stocking, survey, access, and regulation record above. The current season opens first.
Spring
trout- Start here
- Cooler water, recent stocking, fish moving shallow, and protected shorelines or inlets that warm first.
- Watch for
- Cold fronts, changing water levels, muddy inflow, and early-season ramp conditions.
Summer
listed species- Start here
- Fish early or late, then adjust toward deeper water, shade, vegetation, or comfortable temperature zones.
- Watch for
- Warm water, weeds, algae, heat, and heavier boat traffic.
Fall
trout- Start here
- Cooling water, shoreline structure, points, weed edges, and simple presentations that let you cover water.
- Watch for
- Wind on open water, rapidly changing weather, and shorter daylight windows.
Winter
trout- Start here
- Legal open-water or ice access, stable depth zones, and conservative cold-weather trip plans.
- Watch for
- Ice safety where relevant, ramps, road conditions, cold-water exposure, and current rules.
Know before you go
Rules and restrictions
Check current Montana Western District regulations and any posted access-site restrictions before fishing.
Official field updates Recent surveys and fishing pressure
Official surveys and pressure information can help with trip planning. Conditions change, and these updates do not guarantee current fishing.
Rainbow trout, Westslope cutthroat trout
Montana FishMT provides an official Harpers Lake waterbody page with public waterbody information, fish species, and survey data sections. Use as source-available survey context, not live catch data.
Rainbow trout, Westslope cutthroat trout
Montana Fish, Wildlife & Parks FishMT source check includes fishery survey, sampling, or population context for Harpers Lake. This supports species planning for Rainbow trout, Westslope cutthroat trout, not guaranteed success.
Rainbow trout, Westslope cutthroat trout
FishMT provides official map and waterbody context for Harpers Lake. Use as access-planning context and verify ramps, restrictions, and site conditions before travel.
Rainbow trout, Westslope cutthroat trout
FishMT Harpers Lake page includes Harpers Lake FAS and day-use imagery plus waterbody information. Use as access/source context for family and trout planning.
Explore by region or target
More ways to explore this fishery
Use FishyNW fishing hubs to compare this water with other relevant lakes and rivers without starting another search.
Keep exploring
Nearby waters
The four closest FishyNW lake guides by straight-line distance.
Browns Lake
21.4 miles away · Lake
Targets include Rainbow Trout, Cutthroat Trout, Brook Trout.
Upsata Lake 30.2 miles away · LakeTargets include Yellow Perch, Northern Pike, Largemouth Bass.
Salmon Lake 32.2 miles away · LakeTargets include Kokanee, Northern Pike, Yellow Perch.
Georgetown Lake 32.8 miles away · LakeTargets include Rainbow Trout, Brook Trout, Kokanee.
Did you know?
What makes Harpers Lake distinctive
At roughly 14.0 acres, Harpers Lake is a compact fishery where shoreline structure can dominate the lake.
Harpers Lake sits at roughly 3,998 feet in elevation, so seasonal access and water temperature can differ sharply from lowland lakes.
Harpers Lake is documented in Powell County County with a dedicated FishyNW fishing and access profile.
Research & monitoring
Water science & monitoring
Loading available public monitoring and fishery science. Use this as supporting research, not as a live fishing report.
Pass 3 · depth + water column
Seasonal Fish Habitat
Surface · 0 ft
How to read this data
Temperature, dissolved oxygen, clarity, nutrients, chlorophyll-a, pH, and conductivity are observations from public monitoring records and may be historical. Thermocline depth is shown only when FishyNW can derive a strong vertical temperature gradient from a measured profile. It is not treated as a permanent lake characteristic.
Trophic indication uses the Carlson Trophic State Index only when FishyNW can normalize a measured chlorophyll-a, Secchi, or total-phosphorus value. It is a derived ecological indicator, not an agency impairment determination.
Seasonal Fish Habitat is shown only when verified bathymetry overlaps a same-day, same-station temperature and dissolved-oxygen profile. It is a historical screening snapshot, not a live prediction of where fish are located.
For lake trout, FishyNW uses the broader USGS-tested screening combination of water at or below 15°C (59°F) and dissolved oxygen at or above 4 mg/L. For other coldwater species, FishyNW does not invent a preferred-temperature threshold; it shows only the observed thermocline-to-oxygenated-depth refuge when the evidence supports it.
Harmful-algae status is never inferred from missing data. Always check the linked state source for current advisories before contact recreation.
Open matched Water Quality Portal recordsSources & feedback
Verified resources
Official links for this lake
Open the source that matches what you are planning.
Community feedback
See something that needs an update?
Send the correction and, when possible, the source. FishyNW reviews submissions before changing the guide.