Rupel Lake

St. Joseph County, Indiana · IN DNR bathymetric survey

9ft Max
depth

25 acres 9 contours 24% weedy

Paddling Index65MixedMedium confidencesheltered geometry

Get directions

Depth scale

0123456789

The lake

Survey readout

Rupel Lake is mapped to a depth of 9 ft on the Indiana DNR survey and covers about 25 acres in St. Joseph County, Indiana. Depths come from the Indiana DNR survey of 2018.

Measured from the Indiana DNR lake bathymetry survey.

Deepest mapped contour: 9 ft
Survey year: 2018
Surface area: 25 acres
Shoreline: 1.03 mi · lobed
Aquatic vegetation: 24% of surface · NDVI estimate
Public access: No public DNR launch identified

Additional depth details9 contours

Contour depths: 0–9 ft
Recorded point soundings: 9 ft

Compare with another lake

Location

St. Joseph County, Indiana · all 5 lakes · tap a dot for that lake

Chart data

Provenance

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

⚠ Not for navigation

Spot an error? Send a correction

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: 41.52867, -86.41554
IN DNR lake ID: 123165957
Vertical exaggeration: 3.0×
Basemap: USDA NAIP · public domain
Model size: 0.8 MB

Paddling

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

65 / 100MixedData confidence: Medium

Rupel Lake has a partly natural setting, well 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	Good	17.5 of 35	46% natural land cover within 150 m of shore (9% forest, 37% wetland; 0% developed)
Geometric wind exposure	Excellent	29.4 of 29	mean fetch 331 m · 100% of sampled water within 500 m of shelter · short fetch in most directions
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	9.7 of 18	some nearby classified roads · 13 INDOT-classified segments within 1.2 km, peak 6,238 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: Moderate — narrow in places — wakes would carry across parts of the lake
Aquatic vegetation: Moderate — approximately 24% 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 — 9% forest and 37% 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

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

Common Carp

Bigmouth Buffalo

Gizzard Shad

White Perch

Golden Shiner

Brook Silverside

About these fish → the Fish of Indiana guide

Fishing rules for this lake Beta

Size and daily limits for the 20 species found here — 15 open to harvest, 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.

White PerchSpecial rulesAn exotic fish: unlawful to possess alive. If caught it must be killed at once -- head, gill arches or viscera removed (312 IAC 9-6-7).

Bigmouth BuffaloOpen to harvestMinimum size: no size limit · Daily limit: no limit (312 IAC 9-7-14(d) · “Buffalo”)

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)).

Bigmouth BuffaloOpen to harvestMinimum size: no size limit · Daily limit: no limit (312 IAC 9-7-14(d) · “Buffalo”)

Black CrappieOpen to harvestMinimum size: no size limit · Daily limit: 25 (312 IAC 9-7-14(a)) Black and white crappie together.

BluegillOpen to harvestMinimum size: no size limit · Daily limit: no limit (312 IAC 9-7-14(d) · “Bluegill”)

BowfinOpen to harvestMinimum size: no size limit · Daily limit: no limit (312 IAC 9-7-14(d) · “Bowfin”) Roe must stay intact inside the fish while on or beside the water and until processing begins; once removed, roe may not be screened, washed, processed, preserved, stored, kept, given away, sold or transported without a roe harvester's license (312 IAC 9-7-14(f), (g)).

Brook SilversideRule not confidently resolvedNot named in 312 IAC 9-7 or in the DNR guide's limits table. Please check with the Indiana DNR (317-232-4200) before keeping this species.

Brown BullheadOpen to harvestMinimum size: no size limit · Daily limit: no limit (312 IAC 9-7-14(d) · “Bullhead”)

Channel CatfishOpen to harvestMinimum size: no size limit · Daily limit: 10 (312 IAC 9-7-3(b), (d)) The 10 is catfish in aggregate of any size from a lake or reservoir. Of those, not more than one channel catfish 28 inches or longer, one blue catfish 35 inches or longer and one flathead catfish 35 inches or longer per day.

Common CarpOpen to harvestMinimum size: no size limit · Daily limit: no limit (312 IAC 9-7-14(d) · “Carp”)

Gizzard ShadOpen to harvestMinimum size: no size limit · Daily limit: no limit (312 IAC 9-7-14(d) · “Gizzard shad”) No limit on harvest, but live shad may not be kept: live gizzard or threadfin shad may be possessed or used as bait only on eight named waters (Brookville, Cecil M. Harden, Monroe and Patoka reservoirs, Lakes Freeman and Shafer, Hardy Lake, the Ohio River main stem excluding its embayments), and only where collected. Everywhere else shad must be killed immediately (312 IAC 9-6-8(b)–(d)).

Golden ShinerOpen to harvestMinimum size: no size limit · Daily limit: none stated (312 IAC 9-7-15) A minnow under the code’s definition (312 IAC 9-6-1). Minnows may be taken at any time of year by minnow trap, dip net, seine, cast net or lawful sport-fishing methods; the section states no bag or size limit, caps transport out of Indiana at 100 minnows in any 24-hour period (licensed bait dealers, scientific-purposes licensees and those commercially raising minnows in private waters for sale excepted), and requires a bait dealer’s license to sell (312 IAC 9-7-15).

Green SunfishRule not confidently resolvedNot named in 312 IAC 9-7 or in the DNR guide's limits table. Please check with the Indiana DNR (317-232-4200) before keeping this species.

Largemouth BassOpen to harvestMinimum size: 14" · Daily limit: 5 (312 IAC 9-7-6(a), (c)(3)) The 5 is black bass in aggregate — any combination of largemouth, smallmouth and spotted bass — not 5 of each.

Northern PikeOpen to harvestMinimum size: 24" · Daily limit: 3 (312 IAC 9-7-5(a), (b)) No more than one of the three may be over 30 inches.

PumpkinseedRule not confidently resolvedNot named in 312 IAC 9-7 or in the DNR guide's limits table. Please check with the Indiana DNR (317-232-4200) before keeping this species.

Redear SunfishOpen to harvestMinimum size: no size limit · Daily limit: 25 (312 IAC 9-7-14(c))

Spotted GarOpen to harvestMinimum size: no size limit · Daily limit: no limit (312 IAC 9-7-14(d) · “Gar”)

WarmouthRule not confidently resolvedNot named in 312 IAC 9-7 or in the DNR guide's limits table. Please check with the Indiana DNR (317-232-4200) before keeping this species.

White CrappieOpen to harvestMinimum size: no size limit · Daily limit: 25 (312 IAC 9-7-14(a)) Black and white crappie together.

White PerchSpecial rulesAn exotic fish: unlawful to possess alive. If caught it must be killed at once -- head, gill arches or viscera removed (312 IAC 9-6-7).

Yellow BullheadOpen to harvestMinimum size: no size limit · Daily limit: no limit (312 IAC 9-7-14(d) · “Bullhead”)

Official rule text for this lake

“An individual may take minnows at any time during the year.” — 312 IAC 9-7-15(a), Indiana Administrative Code

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 2018

284Fish sampled

20Species

Gamefish Bowfin 17 · Largemouth Bass 10 · Channel Catfish 9 · Northern Pike 1

Panfish Bluegill 143 · Black Crappie 12 · White Crappie 9

All survey species20 species

Gamefish

Bowfin17 caught · to 28″

Largemouth Bass10 caught · to 18″

Channel Catfish9 caught · to 26″

Northern Pike1 caught · to 36″

Panfish

Bluegill143 caught · to 7″

Black Crappie12 caught · to 10″

White Crappie9 caught · to 10″

Green Sunfish5 caught · to 4″

Redear Sunfish2 caught · to 8″

Pumpkinseed1 caught · to 4″

Warmouth1 caught · to 4″

Bullhead & catfish

Brown Bullhead4 caught · to 10″

Yellow Bullhead3 caught · to 11″

Forage & nongame

White Perch19 caught · to 12″

Bigmouth Buffalo17 caught · to 25″

Spotted Gar13 caught · to 30″

Gizzard Shad11 caught · to 21″

Common Carp5 caught · to 25″

Brook Silverside1 caught · to 3″

Golden Shiner1 caught · to 5″

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

Rupel Lake — common questions

How deep is Rupel Lake?

The deepest contour on the Indiana DNR bathymetric survey of Rupel Lake is 9 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 Rupel Lake?

Rupel Lake covers about 25 acres in St. Joseph County, Indiana.

What fish are in Rupel Lake?

Species with survey, catch or recent-stocking evidence include channel catfish, largemouth bass, northern pike, black crappie, bluegill, bowfin. The page lists all 20 species and the evidence behind each.

Is there public access to Rupel Lake?

No public launch for Rupel 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.

More lakes in St. Joseph County