Lake depth chart
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Recent public catches load as you reach this section.
1,393-acre lake in Peterborough County, Ontario. The lake tops out around 26 ft. The depth chart comes from Ontario Ministry of Natural Resources and Forestry bathymetric survey data, so the contours are survey-derived rather than computer-modeled. The depth data here comes from the Ontario MNRF survey of 1962, a decades-old survey (a transect sounding survey). Here is how the season plays out for each species, straight from the data behind the map.
On the chart, Round Lake draws 1,399 acres inside 13.4 miles of shoreline, broken up by 32 islands. With a shoreline index of 2.5, this water is all arms and coves — edge habitat well beyond its acreage. Roughly 52% of the water is 15 ft or less, the band where the food chain lives. The basin spans about 2.4 mi end to end and 1.9 mi across at its widest. You'll find it in Peterborough County. For a second option, Sebright Bay lies 1 mi northeast.
These fish are listed in an exact-water agency record as forage or ecological context. They are not target-species profiles and do not affect DepthScout's Prime, Good, or Fair spot ratings.
Official Ontario MNRF Fish ON-Line record. The listing documents source-recorded presence, not present abundance or guaranteed catchability.
Spring cisco (lake herring) on Round Lake hold shallow, usually 7 to 26 ft. Depth-wise the year is flat: 8 to 26 ft in summer, 8 to 26 ft once it turns cold. Put Deep basin first on the milk run — a deep basin near 26 ft that grades prime for spring. The feeding windows run early morning. The summer box starts with a vertical flutter spoon (small) or a drop-shot micro plastic.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 7 to 26 ft chart-limited; documented 10 to 40 ft | dawn & dusk | Deep basin (26 ft) | Small silver spoon, Tiny swim jig (white) |
| Summer | 8 to 26 ft chart-limited; documented 40 to 80 ft | dawn | Deep basin (26 ft) | Vertical flutter spoon (small), Drop-shot micro plastic |
| Fall | 5 to 25 ft | dusk & dawn | Break off the point (18 ft) | Small casting spoon, Inline spinner (silver) |
| Winter | 8 to 26 ft chart-limited; documented 20 to 60 ft | dawn | Deep basin (26 ft) | Small jigging spoon (glow/silver), Tungsten jig + minnow head |
When the water first warms, walleye slide up into 4 to 15 ft. By summer they slide out to 8 to 26 ft, and by winter most fish are in 8 to 26 ft. If you only fish one area, make it Break off the point: a drop-off around 18 ft that scores prime in fall. In summer the feeding windows fall in the evening and early morning. Keep a crawler harness on bottom bouncer or a deep crankbait (trolled) rigged through the warm months.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 4 to 15 ft | dusk & dawn | Main-lake point (1 ft) | 1/8 oz jig + minnow, Hair jig |
| Summer | 8 to 26 ft chart-limited; documented 15 to 35 ft | dusk & dawn | Break off the point (18 ft) | Crawler harness on bottom bouncer, Deep crankbait (trolled) |
| Fall | 8 to 26 ft chart-limited; documented 12 to 40 ft | dusk & night | Break off the point (18 ft) | Jigging rap, Jig + big minnow |
| Winter | 8 to 26 ft chart-limited; documented 20 to 40 ft | dusk & dawn | Deep basin (26 ft) | Jigging spoon + minnow head, Rattle bait |
When the water first warms, yellow perch slide up into 3 to 12 ft. Summer is an 8 to 26 ft game here, winter an 8 to 26 ft one. Start at Deep basin. It's a deep basin holding about 26 ft of water and rates prime come fall. The feeding windows run early morning. Keep a drop-shot micro plastics or a small spoon tipped with worm rigged through the warm months.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | midday & dawn | Shallow bay flat (2 ft) | Small jig + curly tail, Perch-pattern micro crank |
| Summer | 8 to 26 ft chart-limited; documented 10 to 30 ft | dawn | Deep basin (26 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 8 to 26 ft chart-limited; documented 12 to 35 ft | midday | Deep basin (26 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 8 to 26 ft chart-limited; documented 15 to 35 ft | midday & dawn | Deep basin (26 ft) | Tungsten jig + spikes, Rattle spoon (small) |
Spring puts muskellunge in skinny water — 3 to 12 ft is the zone. Warm water sends them out to 8 to 25 ft; cold water stacks them in 8 to 26 ft. Break off the point is the standout, a drop-off at roughly 18 ft, rated prime for fall muskellunge. Plan around the evening and early morning in the warm months. A double-10 bucktail or a topwater (walk-the-dog / creeper) covers the summer program.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | dusk | Shallow bay flat (2 ft) | Smaller bucktail (#8 blades), 6" glide bait |
| Summer | 8 to 25 ft | dusk & dawn | Break off the point (18 ft) | Double-10 bucktail, Topwater (walk-the-dog / creeper) |
| Fall | 7 to 26 ft chart-limited; documented 8 to 30 ft | midday & dusk | Break off the point (18 ft) | Big rubber (Bull Dawg style), 10"+ glide bait |
| Winter | 8 to 26 ft chart-limited; documented 15 to 35 ft | midday | Deep basin (26 ft) | Large rubber, crawled slow |
The spring pattern is a shallow one: smallmouth bass in 3 to 12 ft. Midsummer fish sit out in 8 to 26 ft before dropping to 8 to 26 ft for winter. The spot to know is Break off the point, a drop-off in about 18 ft of water that rates prime for smallmouth bass in winter. Plan around early morning and the evening in the warm months. Summer baits: a drop shot (goby/minnow) or a ned rig gets it done.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | dawn & dusk | Main-lake point (1 ft) | Ned rig, Tube jig |
| Summer | 8 to 26 ft chart-limited; documented 10 to 30 ft | dawn & dusk | Break off the point (18 ft) | Drop shot (goby/minnow), Ned rig |
| Fall | 8 to 25 ft | midday & dawn | Break off the point (18 ft) | Jerkbait, Blade bait |
| Winter | 8 to 26 ft chart-limited; documented 20 to 45 ft | midday | Break off the point (18 ft) | Blade bait, Hair jig |
Start shallow in spring: largemouth bass sit in 2 to 10 ft that time of year. Warm water sends them out to 8 to 20 ft; cold water stacks them in 8 to 26 ft. Top water on the chart: Shallow bay flat, a weed flat in the 2 ft range, prime in spring. Fish it in early morning and the evening and you'll meet the bite. Throw a texas-rigged 10" worm or a deep-diving crankbait until the fish tell you otherwise.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 10 ft | dawn & dusk | Shallow bay flat (2 ft) | Spinnerbait, Chatterbait |
| Summer | 8 to 20 ft | dawn & dusk | Break off the point (18 ft) | Texas-rigged 10" worm, Deep-diving crankbait |
| Fall | 4 to 15 ft | midday & dawn | Main-lake point (1 ft) | Squarebill crankbait (shad), Spinnerbait |
| Winter | 8 to 26 ft chart-limited; documented 15 to 35 ft | midday | Break off the point (18 ft) | Blade bait, Jigging spoon |
Round Lake also holds rock bass (5 to 20 ft in summer), bluegill (4 to 15 ft in summer), pumpkinseed (2 to 10 ft in summer), brown bullhead (3 to 12 ft in summer). Pick any of them on the map above for rated spots and bait picks.
Count 6 structure marks on this chart. The deepest, Deep basin, sits near 26 ft.
Access data: Geospatial Ontario - Fishing Access Points; Government of Ontario - MNR Unpatented Crown Land Shoreline; Government of Ontario - MNR Unpatented Crown Land Shoreline. Confirm conditions and fees locally before you launch.
Season dates, license requirements, and size and bag limits for Ontario waters are set by the Ontario fishing regulations (FMZ summary) — and special regulations can apply to Round Lake specifically, so confirm the current rules before you fish.
Check the official Ontario fishing regulations →
Round Lake is about 26 ft (8 m) deep at its deepest point. The depth data here comes from the Ontario MNRF survey of 1962, a decades-old survey (a transect sounding survey).
Anglers target cisco (lake herring), walleye, yellow perch, muskellunge, smallmouth bass, largemouth bass, rock bass, bluegill, pumpkinseed, brown bullhead on Round Lake.
Deep basin is the top-rated area: a deep basin in about 26 ft of water that rates prime for cisco (lake herring) in spring. The interactive chart above rates every spot for each species and season.
For cisco (lake herring), the summer bite is best in early morning. Each species page section below lists the seasonal windows, and the map shows a live NOW badge when you're inside one.
Fishing on Round Lake is regulated by the Ontario fishing regulations (FMZ summary). Check the official Ontario regulations for current license requirements, season dates, and size and bag limits — special regulations can apply to this specific water.
Sebright Bay 1 mi · Belmont Lake 3 mi · Lanes Lake 4 mi · Beloporine Lake 4 mi · Lost Lake 4 mi · Cordova Lake 6 mi · Oak Lake 7 mi · Crowe Lake 7 mi · Twin Sister L.s 9 mi · Kasshabog Lake 11 mi · Dummer Lake 11 mi · Thomson Lake 11 mi
See how Round Lake stacks up: best largemouth bass lakes in Ontario · best smallmouth bass lakes in Ontario · best walleye lakes in Ontario · best bluegill lakes in Ontario
More water nearby: Peterborough County fishing maps (83 charts). Browse all Ontario fishing maps. See every water on DepthScout. Bathymetry: published agency survey data. 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.