Lake Beulah
Walworth County, Wisconsin812 acresView mapDirections
Wisconsin DNR publishes the water-quality measurements for Lake Beulah. Here is what has been measured.
- Mesotrophic
- Impaired · Nutrients (phosphorus, nitrogen)
- 3 aquatic invasives
- 58 ft max depth
- Public access
Lake Beulah in Walworth County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 10 ft visibility. Phosphorus: 13.4 µg/L. Chlorophyll-a (algae): 2.5 µg/L. Maximum depth: 58 ft. Surface area: 812 acres.
Wisconsin DNR lists Panfish as common on Lake Beulah. DNR survey details →
Lake Beulah is a 812-acre mesotrophic lake in Walworth County, Wisconsin with a maximum depth of 58 feet. Overall water quality is improving over recent sampling years. The lake supports 3 documented fish species including Panfish, Largemouth Bass, and Northern Pike. Public access is available. Compared to the 18 other monitored lakes in Walworth County, Lake Beulah ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2026-05-08. Methodology: how these readings are compared.
What Lake Beulah is good for
From access and monitoring records, not editorial picks.
- Clear water10 ft of visibility
- Fishing3 species recorded
- Deep water58 ft surveyed max depth
Swimming conditions
Readings onlyRecreation use not supported
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrient and algae readings are not a swimming clearance. Lake Beulah is listed impaired under Clean Water Act §303(d) (IR 5) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.
Whether Lake Beulah 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 Lake Beulah
These are the measurements Wisconsin DNR publishes for Lake Beulah, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Good clarity, visible to about 10 ft. Phosphorus 13.4 µg/L. Chlorophyll-a 2.5 µg/L. TSI 42.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 10ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 13.4µg/L | Good GoodFairPoor |
| Chlorophyll-a (algae) | 2.5µg/L | Good GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 42 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Lake Beulah
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Lake Beulah typically sits around 72°F at the surface in September. Summer average is about 80°F. Usually warmest in Jun (about 82°F) and coldest in May (about 58°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (58°F) to its warmest (82°F).
Typical surface water temperature by month, from 14 field readings (2024–2026) via the EPA Water Quality Portal. See the full Lake Beulah water temperature breakdown →
Blue-Green Algae (Cyanobacteria)
There’s no recent EPA CyAN cyanobacteria estimate for Lake Beulah — clouds, ice, or an off-season gap in coverage. The most recent reading was high (222,844 cells/mL) on March 28, 2026.
Blue-green algae can appear and clear within days, so check your state’s current advisory before swimming. EPA CyAN ↗
Wisconsin DNR lists Panfish as common on Lake Beulah.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Lake Beulah’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is improving. 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. Monitored by volunteers since 1991. 7 stations on file (most recent sample 2026).
Fish Species (DNR-rated)
Lake Details
Max depth
58 ft
Surface area
812 acres
Public access
Yes
Listed by Wisconsin DNR
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Stays near Lake Beulah
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Top-rated places to stay near Lake Beulah
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Fish Species
Click a species to see every lake where it is documented.
Fishing Lake Beulah
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 Trend: Improving
Based on 6 years of monitoring (2020–2025).
Water clarity
Improving6 years
Phosphorus
Improving-0.61 µg/L/yr6 years
Chlorophyll-a
Worsening+0.1 µg/L/yr3 years
Reservoir Info (USACE NID)
Lake Beulah is a man-made reservoir impounded by the Lake Beulah (completed 1840), built primarily for recreation on the Lake Beulah Outlet; gravity-type dam, 14 ft tall and 300 ft long.
- Surface area
- 834 ac
- Normal storage
- 5,000 ac-ft
- Max storage
- 7,000 ac-ft
- Drainage area
- 10 sq mi
- Hazard class
- High
- Owner
- Lake Beulah Management District;Walworth County
Source: USACE National Inventory of Dams, NID ID WI00699 · Operator website
EPA Impairment Status
Lake Beulah 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: Aquatic life, Recreation.
Source: EPA ATTAINS assessment unit WI10000591 · Official waterbody report
Regulated Pollution Sources Nearby
1 EPA-permitted facility operate within about 5 miles of Lake Beulah under Clean Water Act (NPDES) discharge permits, including 1 classified by the EPA as major discharger.
- Plymouth Tube Co East Troy & Trent PlantsEast Troy · 1.7 mi away · NPDES WI0038938Major
Facilities permitted to discharge under the Clean Water Act within ~5 miles; proximity does not by itself mean a facility affects this lake. Source: EPA ECHO (ICIS-NPDES), as of 2026-07.
Nearby Lakes in Walworth County
Frequently asked questions about Lake Beulah
Where is Lake Beulah?
- Lake Beulah is a lake in Walworth County, Wisconsin. Its water-quality measurements are published by Wisconsin DNR and shown on this page as reported.
What is the water quality of Lake Beulah?
- Lake Beulah in Walworth County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Water clarity: 10 ft visibility. Phosphorus: 13.4 µg/L. Chlorophyll-a (algae): 2.5 µg/L. Maximum depth: 58 ft. Surface area: 812 acres.
Is Lake Beulah safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Lake Beulah is listed impaired under Clean Water Act §303(d) (IR 5) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.
What is the water temperature of Lake Beulah?
- Lake Beulah typically sits around 72°F at the surface in September, from 14 EPA Water Quality Portal field readings (2024–2026). That is a typical value for the month, not a live reading.
How deep is Lake Beulah?
- Lake Beulah has a maximum depth of 58 feet. The lake covers 812 acres.
What fish are in Lake Beulah?
- Fish species found in Lake Beulah include Panfish, Largemouth Bass, Northern Pike. Lake Beulah is located in Walworth County, Wisconsin.
What did the DNR fisheries survey find at Lake Beulah?
- Wisconsin DNR lists Panfish as common on Lake Beulah. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Lake Beulah’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is improving. Catch rate is not a swim clearance and is not a weekly bite report.
Does Lake Beulah have blue-green algae?
- There is no recent EPA CyAN cyanobacteria estimate for Lake Beulah (clouds, ice, or an off-season gap). The most recent reading was high (222,844 cells/mL). Blue-green algae can appear and clear within days, so check Wisconsin's current advisory before swimming.
Can I fish at Lake Beulah?
- Public access to Lake Beulah is listed as yes on the lake record. 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 Lake Beulah across LakeQuality
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Where this data comes from
147 measurements from 6 monitoring stations, 2020–2026. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Wisconsin Department of Natural Resources
WIDNR_WQX95 samples · 2020–2026 - USGS Wisconsin Water Science Center
USGS-WI52 samples · 2020–2022
Analytical methods
- Phosphorus by Colorimetry
- Turbidity in Water
Monitoring station identifiers (6)
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
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Fish and recreation data from Wisconsin DNR Lakes