Johanna Lake
Ramsey County, Minnesota212 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Johanna Lake. Here is what has been measured.
- Eutrophic
- Impaired · PFAS
- 2 aquatic invasives
- 43 ft max depth
- Public access
Johanna Lake in Ramsey County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 6.6 ft visibility. Phosphorus: 41 µg/L. Chlorophyll-a (algae): 8 µg/L. Maximum depth: 43 ft. Surface area: 211.91 acres.
Minnesota DNR's Standard Survey on August 9, 2021 caught 2.50 walleye per gill net at Johanna Lake. DNR survey details →
Johanna Lake is a 212-acre productive, nutrient-rich eutrophic lake in Ramsey County, Minnesota with a maximum depth of 43 feet (17-foot average). Overall water quality is declining over recent sampling years. The lake supports 13 documented fish species including black crappie, bluegill, and bowfin (dogfish). Public access is available with 1 public boat landing. Compared to the 43 other monitored lakes in Ramsey County, Johanna Lake ranks #19 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-22. Methodology: how these readings are compared.
What Johanna Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Fishing13 species recorded
- Ice seasonIce-out around Apr 5
- Deep water43 ft surveyed max depth
Swimming conditions
Readings onlyBacteria tested: low
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.
Based on E. coli testing, Johanna Lake rarely exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 4.3% of 92 samples across 3 seasons.
This is a historical summary of past testing, not a current condition — bacteria levels change quickly, especially after rain. Always check Minnesota’s current beach and health-department advisories before swimming.
Whether Johanna Lake is safe to swim in today is a call for the Minnesota Pollution Control Agency and the Minnesota DNR and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Johanna Lake
These are the measurements Minnesota PCA publishes for Johanna Lake, 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 6.6 ft. Phosphorus 41 µg/L. Chlorophyll-a 8 µg/L. TSI 53.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 6.6ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 41µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 8µg/L | Fair GoodFairPoor |
| 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 Johanna Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Johanna Lake typically sits around 51°F at the surface in October. Summer average is about 62°F. Usually warmest in Jul (about 64°F) and coldest in Feb (about 35°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (35°F) to its warmest (64°F).
Typical surface water temperature by month, from 1,092 field readings (2010–2025) via the EPA Water Quality Portal. See the full Johanna Lake water temperature breakdown →
Minnesota DNR's Standard Survey on August 9, 2021 caught 2.50 walleye per gill net at Johanna Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Johanna Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
11 surveys on file from MN DNR Fisheries. Most recent: 2021-08-09 (Standard Survey).
11 surveys on file · most recent 2021-08-09 (Standard Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Bluegill | 59.04 | 1–9 in 2021-08-09 | 0.13 lb |
| Yellow Perch | 19.05 | 5–7 in 2021-08-09 | 0.1 lb |
| Black Crappie | 11.74 | 4–10 in 2021-08-09 | 0.14 lb |
| Northern Pike | 4.32 | 9–37 in 2021-08-09 | 3.77 lb |
| Pumpkinseed | 2.98 | 3–6 in 2021-08-09 | 0.12 lb |
| Largemouth Bass | 2.87 | 4–17 in 2021-08-09 | 0.71 lb |
CPUE = catch per unit effort, fish caught per net per set in a standardised survey. It measures abundance, not size, and is not a weekly bite report.
Length Distributions
Number of fish caught at each inch class in the most recent survey that recorded lengths. Red dashed line marks an approximate trophy threshold for that species.
Bluegill
Yellow Perch
Black Crappie
Northern Pike
From the 2021-08-09 survey
Lake Johanna is a 213-acre, eutrophic lake located in Arden Hills, 7.5 miles northwest of St. Paul. The contributing watershed is characterized by residential, commercial, industrial and major roadways. Overall, water quality in Lake Johanna is very good. The most recent data indicates that it is one of the best lakes…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Johanna Lake. 3 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — JohannaFisheries Lake Survey · MN DNR LakeFinder
- —Fish Stocking History — JohannaFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — JohannaPublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
43 ft
Average depth
17 ft
Surface area
212 acres
Shoreline
3 mi
Littoral zone
45%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Recreation & Access
- Johanna LakePublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Johanna Lake
Compare lakeside cabins, hotels, and vacation rentals near Johanna Lake in Ramsey County, Minnesota — 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. The water-quality readings cover nutrients and algae, not lodging. Cabins and rentals around Johanna Lake are listed below.
Top-rated places to stay near Johanna Lake
Prices for Oct 9–11, 4 adults. Change dates on the map below.
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a whole trip? See where to stay at Minnesota’s top lakes →
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Fish Species
Click a species to see every lake where it is documented.
Fishing Johanna Lake
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: Worsening
Based on 6 years of monitoring (2020–2025).
Water clarity
Worsening6 years
Phosphorus
Worsening+1.5 µg/L/yr6 years
Chlorophyll-a
Worsening+2.43 µg/L/yr6 years
Ice season
Typical ice-out
Apr 5
Earliest Mar 8, 2000 · Latest Apr 29, 2013
Typical ice-in
Dec 3
Earliest Nov 30, 1994 · Latest Dec 14, 2004
Most recent ice-out
Apr 29
2013
15 observations · Minnesota PCA ice records
EPA Impairment Status
Johanna Lake 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, Fish consumption.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN62-0078-00 · Official waterbody report
Nearby Lakes in Ramsey County
Frequently asked questions about Johanna Lake
Where is Johanna Lake?
- Johanna Lake is a lake in Ramsey County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Johanna Lake?
- Johanna Lake in Ramsey County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 6.6 ft visibility. Phosphorus: 41 µg/L. Chlorophyll-a (algae): 8 µg/L. Maximum depth: 43 ft. Surface area: 211.91 acres.
Is Johanna Lake safe to swim in?
- Based on E. coli testing, Johanna Lake rarely exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 4.3% of 92 samples across 3 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 Johanna Lake is safe to swim in today is a call for Minnesota's water agency and the county health department; check their current beach advisories before you swim.
What is the water temperature of Johanna Lake?
- Johanna Lake typically sits around 51°F at the surface in October, from 1,092 EPA Water Quality Portal field readings (2010–2025). That is a typical value for the month, not a live reading.
How deep is Johanna Lake?
- Johanna Lake has a maximum depth of 43 feet and an average depth of 17 feet. The lake covers 211.91 acres.
What fish are in Johanna Lake?
- Fish species found in Johanna Lake include black crappie, bluegill, bowfin (dogfish), green sunfish, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, tiger muskellunge, walleye, white sucker, yellow bullhead, yellow perch. Johanna Lake is located in Ramsey County, Minnesota.
What did the DNR fisheries survey find at Johanna Lake?
- Minnesota DNR's Standard Survey on August 9, 2021 caught 2.50 walleye per gill net at Johanna Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Johanna Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
When does Johanna Lake thaw?
- Johanna Lake typically has ice-out around Apr 5. Ice typically forms around Dec 3. The open water season is approximately 242 days.
Are there boat ramps on Johanna Lake?
- Johanna Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Johanna Lake. Public access is listed as yes.
Can I fish at Johanna Lake?
- Johanna Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Minnesota's fish and wildlife agency, so check its current regulations before you go.
Explore Johanna Lake across LakeQuality
Depth, room, public access, and the state wake-sport rules
Fish species and the cleanest lakes across Minnesota
Fish species and best lakes in Ramsey County
Species activity outlook by water temperature and season
Where to stay at Minnesota's top lakes, each with its readings
Minnesota's cleanest lakes, ranked on agency measurements
More lakes in Minnesota
State Parks Near Johanna Lake
Other Lakes in Minnesota
Eutrophic Lakes in Minnesota
Where this data comes from
431 measurements from 4 monitoring stations, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA431 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Colorimetry
- Phosphorus by Two Reagent Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
- 2130 B ~ Nephelometric Method
- Turbidity by Nephelometry
Monitoring station identifiers (4)
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 details from Minnesota DNR LakeFinder
Named boat-access points from the USGS National Boat Ramps inventory
Ice data from Minnesota DNR Climate