South Twin Lake

LaGrange County, Indiana · IN DNR bathymetric survey

50ft Max
depth

116 acres 10 contours

Paddling Index50ModestMedium confidencesheltered geometry

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Depth scale

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The lake

Survey readout

South Twin Lake is mapped to a depth of 50 ft on the Indiana DNR survey and covers about 116 acres in LaGrange County, Indiana.

Measured from the Indiana DNR lake bathymetry survey.

Deepest mapped contour: 50 ft
Surface area: 116 acres
Shoreline: 1.75 mi · round
Aquatic vegetation: 2% of surface · NDVI estimate
Public access: No public DNR launch identified

Additional depth details10 contours

Contour depths: 0–50 ft
Recorded point soundings: 50 ft

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Location

LaGrange County, Indiana · 15 nearest of 20 lakes · tap a dot for that lake

Chart data

Provenance

Sources: IN DNR Lake Bathymetry, USGS 3DEP, USDA NAIP (public domain), OpenStreetMap (ODbL).

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Map details & sources4 sources

All layers registered to one bounding box; positions in WGS 84.

Survey-derived depth contours drape over USGS 3DEP elevation, with a USDA NAIP aerial basemap and OpenStreetMap shoreline. Color shows surveyed depth; dark lines are the survey's own isobaths.

Coordinates: 41.72476, -85.46619
IN DNR lake ID: south-twin-lake
Vertical exaggeration: 1.98×
Basemap: USDA NAIP · public domain
Model size: 2.1 MB

Paddling

Paddling Index methodology v1.0 · calculated 2026-09-21

50 / 100ModestData confidence: Medium

South Twin Lake has a mixed natural and developed setting, generally sheltered geometry, some nearby classified roads. No special watercraft restriction is identified in the current source.

Why this score?5 components

Included in the index

Component	Rating	Points of weight	Measurement
Natural setting	Mixed	10.2 of 35	42% natural land cover within 150 m of shore (6% forest, 35% wetland; 31% developed)
Geometric wind exposure	Very Good	22.1 of 29	mean fetch 732 m · 0% of sampled water within 500 m of shelter · generally short fetch
Watercraft controls	None identified	8.8 of 18	No special watercraft restriction identified in the current DNR source. Motors permitted, subject to general law.
Public access	Not listed	—	No DNR-listed access site. Township, county and road-end launches are not in this source, so this is not evidence that access is poor — the component is excluded and the remaining weights are renormalized.
Road isolation	Good	9.2 of 18	some nearby classified roads · 1 INDOT-classified segment within 1.2 km, peak 4,824 vehicles/day

Additional paddling considerations

These describe the lake but are not part of the v1 Paddling Index and do not change the number above.

Wake sensitivity: Low — wide enough that wakes disperse over most of the lake
Aquatic vegetation: Low — approximately 2% mapped coverage · NAIP aerial imagery (NDVI)
Observed motorized activity: Unknown — No lake-level measurement of boat traffic is available. Legal permission to operate motors is not evidence of use.
Wildlife habitat potential: Moderate — 6% forest and 35% wetland cover within 150 m of shore

Compare Indiana lakes by Paddling Index →

How this index is calculated. The Paddling Index is a relative composite derived from lake geometry and public environmental, access, roadway and watercraft-control data. It is not a user review, a safety rating, or a prediction of an individual outing. Differences of a few points should not be treated as meaningful — an 84 and an 82 are broadly comparable. Components and weights: natural setting 30%, geometric wind exposure 25%, watercraft controls 15%, public access 15%, road isolation 15%; observed motorboat activity is weighted 0% because no defensible lake-level measurement exists. Where a component has no data the remaining weights are renormalized and the confidence rating is lowered; below Medium confidence no number is shown. Sources: USGS NHD waterbody outline, USGS/MRLC NLCD Land Cover (2021), IN DNR Fishing Access Sites (motor restrictions) (2026-08) and INDOT Annual Average Daily Traffic (2021). Conditions change quickly — check current weather and local conditions before going out.

Fish you might catch

from DNR surveys

1 species with recent evidence in this lake — sized relative to each other. Illustrations are AI-generated representative adults in everyday colors, not photographs (provenance).

Cisco

About these fish → the Fish of Indiana guide

Fishing rules for this lake Beta

Size and daily limits for the 1 species found here — 1 with a special rule or closed season.

These are hook-and-line size and daily limit rules. The fishing code sets no closed season for these species on inland lakes, but posted property rules can close a water — see the notes. Gear, spearing and bow fishing, netting and bait collection are set by other sections of 312 IAC 9 and are not shown here.

CiscoClosedEndangered in Indiana — it is illegal to take or possess this fish at any time (312 IAC 9-6-9; IC 14-22-34-12). Release it immediately, unharmed.

Beta. This panel is newly published. Every value is transcribed from the Indiana Administrative Code (312 IAC 9-7) and checked against the Indiana DNR's 2026-27 Fishing Regulations Guide, but the coverage and wording are still under review. If anything here disagrees with 312 IAC 9-7 or the Indiana DNR's guide, the DNR is right — the Administrative Code is the legal text; the guide summarizes it.

No closed season in the fishing code: 312 IAC 9-7 sets no season for these species on inland lakes (trout and salmon “at any time of year”, 9-7-13(d)(1)). Posted property rules can still close a water or bar entry (312 IAC 8-2-1) and 312 IAC 9-6-6 closes a few named areas, so check the property before you go. The possession limit is twice the daily bag limit (312 IAC 9-1-12.1); fish already processed and stored at your primary residence do not count toward it (312 IAC 9-2-8(d)).

CiscoClosedEndangered in Indiana — it is illegal to take or possess this fish at any time (312 IAC 9-6-9; IC 14-22-34-12). Release it immediately, unharmed.

From 312 IAC 9-7 (Sport fishing), Indiana Administrative Code (readopted 2025-03-25), and the 2026-2027 Indiana Fishing Regulations Guide · verified 2026-09-15. Regulations can change — the Indiana Administrative Code (312 IAC 9-7) is the controlling source; verify current regulations before fishing. Official regulations

Compiled from Indiana DNR fishery surveys. Silhouettes are stylized and scaled to typical adult sizes relative to one another. Presence is not a promise — fishing isn’t a sure thing.

Fishery

surveyed 2023

119Fish sampled

1Species

Forage & nongame

Cisco119 caught · to 12″

Length is the largest fish netted in the survey, not an angler record. Source: Indiana DNR fish survey (Indiana Data Hub) (counts summed across survey years).

Non-native species records

No non-native species recorded in the available dataset. This does not confirm that no non-native species are present.

Source: Midwest Glacial Lakes Partnership Conservation Planner; underlying nonindigenous species records from the USGS Nonindigenous Aquatic Species database.

Quick answers

South Twin Lake — common questions

How deep is South Twin Lake?

The deepest contour on the Indiana DNR bathymetric survey of South Twin Lake is 50 ft. That is the deepest depth the historical survey map records, which may differ from the deepest point of the lake itself.

How big is South Twin Lake?

South Twin Lake covers about 116 acres in LaGrange County, Indiana.

What fish are in South Twin Lake?

Species with survey, catch or recent-stocking evidence include cisco. The page shows the evidence behind each.

Is there public access to South Twin Lake?

No public launch for South Twin Lake is shown in the Indiana DNR's public access data. That is not the same as the lake being private -- municipal and private ramps are not in that source.

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