Caldron Falls Reservoir
Marinette County, Wisconsin1,063 acresView mapDirections
Wisconsin DNR publishes the water-quality measurements for Caldron Falls Reservoir. Here is what has been measured.
- Impaired · Mercury
- 2 aquatic invasives
- 40 ft max depth
- Public access
- Limited data
Caldron Falls Reservoir in Marinette County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 5.2 ft visibility. Maximum depth: 40 ft. Surface area: 1063 acres.
Wisconsin DNR lists Musky as common on Caldron Falls Reservoir. DNR survey details →
Caldron Falls Reservoir is a 1,063-acre lake in Marinette County, Wisconsin with a maximum depth of 40 feet. The lake supports 5 documented fish species including Musky, Panfish, and Largemouth Bass. Public access is available with 4 public boat landings.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2024-09-20. Methodology: how these readings are compared.
Caldron Falls Reservoir covers about 1,100 acres in Marinette County. It has 4 public boat landings, so a lakefront rental is not the only way to get a boat on the water. For a place on the water, look through cabin and lake-house rentals near Caldron Falls Reservoir on Vrbo. For a hotel or motel room, Booking.com and Expedia both search around the lake.
What Caldron Falls Reservoir is good for
From access and monitoring records, not editorial picks.
- Boat launch4 documented ramps
- Fishing5 species recorded
- Deep water40 ft surveyed max depth
- Big water1,063 acres
Swimming conditions
No readingBacteria tested: low
Based on E. coli testing, Caldron Falls Reservoir never exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 0% of 112 samples across 9 seasons.
This is a historical summary of past testing, not a current condition — bacteria levels change quickly, especially after rain. Always check Wisconsin’s current beach and health-department advisories before swimming.
Whether Caldron Falls Reservoir is safe to swim in today is a call for the Wisconsin Department of Natural Resources and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Caldron Falls Reservoir
These are the measurements Wisconsin DNR publishes for Caldron Falls Reservoir, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Murky, only visible to about 5.2 ft. TSI 53.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 5.2ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | No reading The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential. | |
| Chlorophyll-a (algae) | No reading The green pigment in algae — a direct measure of how much algae is in the water. | |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 53 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Caldron Falls Reservoir
Answers come straight from the public measurements and survey records on this page.
Wisconsin DNR lists Musky as common on Caldron Falls Reservoir.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Caldron Falls Reservoir’s water-quality measurements separately, and the water-quality trend over 3 years of monitoring is stable. Catch rate is not a swim clearance and is not a weekly bite report.
WI DNR Lake Profile
Authoritative data from the Wisconsin DNR LakePages. 5 stations on file (most recent sample 2024).
Fish Species (DNR-rated)
DNR Reports & Resources
Wisconsin DNR Fisheries scientists publish multi-year survey reports for Caldron Falls Reservoir covering fish populations, stocking, water quality, and management. 1 report on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- 2012Caldron Falls Flowage comprehensive fishery survey 2012Comprehensive Survey · WI DNR · 2012 (PDF)
Lake Details
Max depth
40 ft
Surface area
1,063 acres
Public access
Yes
Listed by Wisconsin DNR
Lake Size & Watershed
Watershed (drainage) area
491 sq mi
HydroLAKES / HydroSHEDS
Shoreline
16.3 mi
HydroLAKES / HydroSHEDS
Elevation
974 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Caldron Falls Reservoir #8 - Caldron BayPublic
- Caldron Falls Reservoir #9 - Muskellunge PointPublic
- Caldron Falls Reservoir #13 - South BayPublic
- Caldron Falls Reservoir #10 - North BayPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Caldron Falls Reservoir
Compare lakeside cabins, hotels, and vacation rentals near Caldron Falls Reservoir in Marinette County, Wisconsin — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.
Top-rated places to stay near Caldron Falls Reservoir
Prices for Oct 9–11, 4 adults. Change dates on the map below.
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Follow Caldron Falls Reservoir’s readings
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Fish Species
Click a species to see every lake where it is documented.
Fishing Caldron Falls Reservoir
- → Caldron Falls Reservoir fishing: DNR survey catch rates, species & stocking
- → Caldron Falls Reservoir fishing forecast & best times (species outlook + 14-day solunar calendar)
- → Caldron Falls Reservoir fishing regulations (limits, seasons, special rules)
- → Is it safe to eat fish from Caldron Falls Reservoir? (mercury & PFAS guide)
Invasive & Introduced Species
Red chips are ecologically harmful invasive species. Gray chips are stocked or introduced fish that aren't a current ecological concern.
Water quality readings over time
3 seasons of samples on record (2020–2024). Calling a direction takes at least 4 years of the same measurement.
Water clarity
Stable3 years
Reservoir Info (USACE NID)
Caldron Falls Reservoir is a man-made reservoir impounded by the Caldron Falls (completed 1924), built primarily for hydroelectric on the Peshtigo River; gravity-type dam, 81 ft tall and 1,250 ft long.
- Surface area
- 1,018 ac
- Normal storage
- 11,475 ac-ft
- Max storage
- 11,500 ac-ft
- Drainage area
- 496 sq mi
- Hazard class
- High
- Owner
- Wisconsin Public Service Corporation
All listed purposes: Hydroelectric;Fish and Wildlife Pond;Recreation;Flood Risk Reduction.
Source: USACE National Inventory of Dams, NID ID WI00759 · Operator website
EPA Impairment Status
Caldron Falls Reservoir is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Designated uses not supporting: Fish consumption.
Source: EPA ATTAINS assessment unit WI10001685 · Official waterbody report
Nearby Lakes in Marinette County
Frequently asked questions about Caldron Falls Reservoir
Where is Caldron Falls Reservoir?
- Caldron Falls Reservoir is a lake in Marinette County, Wisconsin. Its water-quality measurements are published by Wisconsin DNR and shown on this page as reported.
What is the water quality of Caldron Falls Reservoir?
- Caldron Falls Reservoir in Marinette County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 5.2 ft visibility. Maximum depth: 40 ft. Surface area: 1063 acres.
Is Caldron Falls Reservoir safe to swim in?
- Based on E. coli testing, Caldron Falls Reservoir never exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 0% of 112 samples across 9 seasons. That is a historical summary of past bacteria testing, not a current reading and not a swimming clearance. Bacteria levels can spike quickly after heavy rain, so whether Caldron Falls Reservoir is safe to swim in today is a call for Wisconsin's water agency and the county health department; check their current beach advisories before you swim.
How deep is Caldron Falls Reservoir?
- Caldron Falls Reservoir has a maximum depth of 40 feet. The lake covers 1063 acres.
What fish are in Caldron Falls Reservoir?
- Fish species found in Caldron Falls Reservoir include Musky, Panfish, Largemouth Bass, Northern Pike, Walleye. Caldron Falls Reservoir is located in Marinette County, Wisconsin.
What did the DNR fisheries survey find at Caldron Falls Reservoir?
- Wisconsin DNR lists Musky as common on Caldron Falls Reservoir. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Caldron Falls Reservoir’s water-quality measurements separately, and the water-quality trend over 3 years of monitoring is stable. Catch rate is not a swim clearance and is not a weekly bite report.
Are there boat ramps on Caldron Falls Reservoir?
- Caldron Falls Reservoir has 4 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Caldron Falls Reservoir #8 - Caldron Bay, Caldron Falls Reservoir #9 - Muskellunge Point, Caldron Falls Reservoir #13 - South Bay, Caldron Falls Reservoir #10 - North Bay. Public access is listed as yes.
Can I fish at Caldron Falls Reservoir?
- Caldron Falls Reservoir has 4 documented boat landings in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Wisconsin's fish and wildlife agency, so check its current regulations before you go.
Explore Caldron Falls Reservoir across LakeQuality
Depth, room, public access, and the state wake-sport rules
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Fish species and best lakes in Marinette County
Species activity outlook by water temperature and season
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Where this data comes from
7 measurements from 1 monitoring station, 2020–2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Wisconsin Department of Natural Resources
WIDNR_WQX7 samples · 2020–2024
Monitoring station identifiers (1)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database
Lake size & watershed from HydroLAKES (HydroSHEDS)
Fish and recreation data from Wisconsin DNR Lakes
Named boat-access points from the USGS National Boat Ramps inventory