Lost Lake Depth Map & Fishing Spots (Mason County, WA)

Hatch outlook

Callibaetis (Speckled Dun)Active window

Typical here: Aug 15 – Sep 15 · the smaller fall brood

nymphthe hours before the midday emergence — nymphs rise off the weed tops in a vertical zigzag that can take hours — sources split between slow 2–4 inch strips with long pauses and a quicker steady retrieve; carry both speeds
dunmidday, roughly 11am into early afternoon
spinnermid-to-late-morning falls

Trout browse the weed-bed edges knocking nymphs loose, then cruise the flats sipping duns at midday — the marquee western lake mayfly.

The midday emergence puts cruisers over weed flats in under 20 ft: a casting bubble with a #14 Callibaetis nymph retrieved dead-slow with pauses is the honest match. Between hatch hours, small spoons and #1 inline spinners along the weed edges and drop-offs pick off the same fish.

The event happens over weed flats and weed-bed edges in 20 ft of water or less

Chironomids (stillwater midges)Active window

Typical here: May 1 – Oct 31

nymphearly morning, start of the day — fish the bloodworm ON the bottom — 4–6 inches off the mud before the emergence starts
pupathe cool morning hours are prime — as the emergence builds, slide the pupa up to 12–15 inches off bottom under the indicator; a little wind chop does the jigging

Concentrates by DEPTH BAND and mud type, not a fixed spot: roughly 20–25 ft in spring, deeper midsummer, in against the feeder creeks in summer heat, 5–25 ft in fall. Match the band.

This one translates almost perfectly: a slip float with a 1/64–1/100 oz midge-pattern jig set 4–15 inches off bottom over a mud flat, dead-sticked with the chop doing the work. Depth control is everything — no moving lure imitates a hanging pupa; the float rig IS the technique.

The event happens over open mud flats alongside weedlines, channels and basin edges; feeder-creek mouths in summer heat

Water boatman fall flightsActive window

Typical here: Aug 25 – Oct 10 · peaks on crisp, bright fall days after the first cold snap

adultmiddday-ish on calm, sunny fall days — the fishable moment is the splashdown: boatmen dive in headfirst trailing an air bubble and make repeated trips back to the surface — a fly or lure that dives nose-first on the drop imitates exactly this

Takes are seldom subtle — trout ravage boatmen as they hit the water and during their subsurface runs.

Tailor-made for hardware: a small 1/16 oz silver-bellied spoon or jig cast AT the rings of a splashdown sinks headfirst exactly like the natural — twitch-pause it back through the top few feet. On flight days fan-cast the shallow weed margins.

The event happens over near-shore shallows, weed beds and shoal margins on calm sunny fall afternoons

Grasshoppers (east-side summer)Active window

Typical here: Jun 15 – Sep 30

adultall day in high summer, best when afternoon wind knocks bugs onto the water

Pulls fish to the windward grassy banks and edges for months — fish the bank the wind blows ONTO.

The friendliest crossover of the summer: on lakes, drift the windward bank with a bubble-and-foam-hopper — the bubble's splash doesn't hurt a hopper presentation. On rivers, the same rig dead-drifted along the undercut grass banks, or small gold spinners under the banks between rises.

The event happens over grassy banks, undercut edges and windward shorelines

Next on this water

Damselfly migration · forageMay 15 – Jul 31 · in ~9 months

Recommendations come from depth structure and seasonal species behavior. Treat them as a starting point, not a guarantee. Contours here are interpolated from real agency depth surveys (state DNR / USACE). Never use for navigation. Always check local regulations.

Loading depth chart…

Recent catches at Lost Lake

Shared by DepthScout anglers. Exact spots stay private, always.

No shared catches here yet — be the first.Log a catch from the map above and share it to put Lost Lake on the board.

Fishing Lost Lake: what the data says

152-acre lake near Mason County. The lake tops out around 60 ft. The depth chart is built from real state fisheries GPS surveys, so the humps, channels and drop-offs you see are measured, not guessed. What follows comes from the same scoring engine that paints the spots above.

Traced from the shoreline, Lost Lake runs 152 acres with 1.9 miles of edge. At index 1.1 the outline is almost a bowl — read the depth changes, not the shoreline. The shallow band under 15 ft claims about 31% of the surface — that's where the groceries are. Call it 0.8 mi long by 0.4 mi wide at the broadest reach. The water lies in Mason County. For a second option, Isabella Lake lies 6 mi east.

Rainbow Trout fishing at Lost Lake

Start shallow in spring: rainbow trout sit in 5 to 20 ft that time of year. Warm water sends them out to 8 to 30 ft; cold water stacks them in 8 to 40 ft. Top water on the chart: Creek inflow, an inflow / creek mouth in the 11 ft range, prime in spring. Fish it in early morning and the evening and you'll meet the bite. Throw a dodger + spoon (deep troll) or a flutter spoon until the fish tell you otherwise.

Season	Depth	Best window	Start at	Go-to baits
Spring	5 to 20 ft	dawn & dusk	Creek inflow (11 ft)	Inline spinner (silver), Small spoon
Summer	8 to 30 ft	dawn & dusk	Creek inflow (11 ft)	Dodger + spoon (deep troll), Flutter spoon
Fall	10 to 35 ft	dawn & dusk	Old creek channel (10 ft)	Casting spoon, Jerkbait over shoals
Winter	8 to 40 ft	dawn	Old creek channel (10 ft)	Jigging spoon, Tube jig (white)

Largemouth Bass fishing at Lost Lake

Spring puts largemouth bass in skinny water — 2 to 10 ft is the zone. As the season builds they drop to 8 to 20 ft, wintering in 15 to 35 ft. Spring largemouth bass concentrate at Back-bay flat, a prime-rated weed flat around 6 ft. Warm-month bites cluster around early morning and the evening. A texas-rigged 10" worm or a deep-diving crankbait covers the summer program.

Season	Depth	Best window	Start at	Go-to baits
Spring	2 to 10 ft	dawn & dusk	Back-bay flat (6 ft)	Spinnerbait, Chatterbait
Summer	8 to 20 ft	dawn & dusk	Shallow bay flat (11 ft)	Texas-rigged 10" worm, Deep-diving crankbait
Fall	4 to 15 ft	midday & dawn	Old creek channel (10 ft)	Squarebill crankbait (shad), Spinnerbait
Winter	15 to 35 ft	midday	Old creek channel (10 ft)	Blade bait, Jigging spoon

Smallmouth Bass fishing at Lost Lake

In spring, smallmouth bass run shallow here, mostly 3 to 12 ft. Summer pushes them deeper, 10 to 30 ft, and winter fish settle into 20 to 45 ft. Creek inflow is the standout, an inflow / creek mouth at roughly 11 ft, rated prime for spring smallmouth bass. Time it for early morning and the evening. You won't need more than a drop shot (goby/minnow) or a ned rig most summer days.

Season	Depth	Best window	Start at	Go-to baits
Spring	3 to 12 ft	dawn & dusk	Creek inflow (11 ft)	Ned rig, Tube jig
Summer	10 to 30 ft	dawn & dusk	Old creek channel (10 ft)	Drop shot (goby/minnow), Ned rig
Fall	8 to 25 ft	midday & dawn	Old creek channel (10 ft)	Jerkbait, Blade bait
Winter	20 to 45 ft	midday	open water	Blade bait, Hair jig

Yellow Perch fishing at Lost Lake

Early season yellow perch use the shallows, holding in 3 to 12 ft. Expect a summer slide to 10 to 30 ft, then a winter hold in 15 to 35 ft. Put Shallow bay flat first on the milk run — a weed flat near 11 ft that grades prime for spring. In summer the feeding windows fall in early morning. Tie on a drop-shot micro plastics or a small spoon tipped with worm and you're in the game.

Season	Depth	Best window	Start at	Go-to baits
Spring	3 to 12 ft	midday & dawn	Shallow bay flat (11 ft)	Small jig + curly tail, Perch-pattern micro crank
Summer	10 to 30 ft	dawn	Shallow bay flat (11 ft)	Drop-shot micro plastics, Small spoon tipped with worm
Fall	12 to 35 ft	midday	Deep basin (60 ft)	Jigging spoon (small), Perch rig / spreader
Winter	15 to 35 ft	midday & dawn	Deep basin (60 ft)	Tungsten jig + spikes, Rattle spoon (small)

Bluegill fishing at Lost Lake

Start shallow in spring: bluegill sit in 1 to 6 ft that time of year. Summer pushes them deeper, 4 to 15 ft, and winter fish settle into 10 to 25 ft. The spot to know is Back-bay flat, a weed flat in about 6 ft of water that rates prime for bluegill in spring. Warm-month bites cluster around early morning and the evening. Throw a small sponge spider (fly) or a micro tube jig until the fish tell you otherwise.

Season	Depth	Best window	Start at	Go-to baits
Spring	1 to 6 ft	midday & dusk	Back-bay flat (6 ft)	1/32 oz jig + micro plastic, Tiny popper (evenings)
Summer	4 to 15 ft	dawn & dusk	Shallow bay flat (11 ft)	Small sponge spider (fly), Micro tube jig
Fall	6 to 18 ft	midday	Shallow bay flat (11 ft)	Micro jig + waxworm, Small spoon tipped
Winter	10 to 25 ft	midday	Shallow bay flat (11 ft)	Tungsten ice jig + plastic, Tiny spoon

Crappie fishing at Lost Lake

In spring, crappie run shallow here, mostly 2 to 8 ft. Summer pushes them deeper, 10 to 25 ft, and winter fish settle into 15 to 35 ft. Old creek channel is the standout, a creek channel at roughly 10 ft, rated prime for fall crappie. Time it for early morning and the evening. You won't need more than a jig trolled/spider-rigged or a small crankbait (trolled) most summer days.

Season	Depth	Best window	Start at	Go-to baits
Spring	2 to 8 ft	midday & dawn	Back-bay flat (6 ft)	1/16 oz jig + tube, Curly-tail grub
Summer	10 to 25 ft	dawn & dusk	Old creek channel (10 ft)	Jig trolled/spider-rigged, Small crankbait (trolled)
Fall	8 to 20 ft	dawn	Old creek channel (10 ft)	Jig + minnow combo, Small swimbait (1.5-2")
Winter	15 to 35 ft	midday	Old creek channel (10 ft)	Tungsten jig + soft plastic, Tiny jigging spoon

Notable structure

Structure-wise the chart holds 5 features, led in depth by Deep basin at roughly 60 ft.

Deep basin: deep basin, around 60 ft
Shallow bay flat: weed flat, around 11 ft
Creek inflow: inflow / creek mouth, around 11 ft
Old creek channel: creek channel, around 10 ft
Back-bay flat: weed flat, around 6 ft

Public access & boat ramps

Lost Lake — ramp (concrete)

Access data: Washington WDFW — Water Access Sites. Confirm conditions and fees locally before you launch.

Lost Lake fishing regulations

Season dates, license requirements, and size and bag limits for Washington waters are set by the Washington Department of Fish and Wildlife — and special regulations can apply to Lost Lake specifically, so confirm the current rules before you fish.

Check the official Washington fishing regulations →

Common questions

How deep is Lost Lake?

Lost Lake is about 60 ft (18 m) deep at its deepest point. The depth chart here comes from real state fisheries GPS surveys, so the contours reflect measured depths.

What fish are in Lost Lake?

Anglers target rainbow trout, largemouth bass, smallmouth bass, yellow perch, bluegill, crappie on Lost Lake.

Where is the best fishing spot on Lost Lake?

Creek inflow is the top-rated area: an inflow / creek mouth in about 11 ft of water that rates prime for rainbow trout in spring. Every other rated spot, per species and season, is on the map above.

When is the best time to fish Lost Lake?

For rainbow trout, the summer bite is best in early morning and the evening. Each species page section below lists the seasonal windows, and the map shows a live NOW badge when you're inside one.

What are the fishing regulations for Lost Lake?

Fishing on Lost Lake is regulated by the Washington Department of Fish and Wildlife. Check the official Washington regulations for current license requirements, season dates, and size and bag limits — special regulations can apply to this specific water.

Nearby waters

Isabella Lake 6 mi · Nahwatzel Lake 7 mi · Island Lake 9 mi · Summit Lake 10 mi · Lake Limerick 13 mi · Forbes Lake 13 mi · Phillips Lake 15 mi · Spencer Lake 15 mi · Black Lake 17 mi · Mason Lake 18 mi · Benson Lake 19 mi · U Lake 20 mi

See how Lost Lake stacks up: best largemouth bass lakes in Washington · best smallmouth bass lakes in Washington · best crappie lakes in Washington · best bluegill lakes in Washington

More water nearby: Mason County fishing maps (14 charts). Browse all Washington fishing maps or see every water on DepthScout. Bathymetry credit: state fisheries survey programs. How we build these maps. Fish here with a sonar unit that logs? Send us your depth data and we'll improve this chart, credited to you. For fishing guidance only, never navigation.