Portage Lake
Hubbard County, Minnesota429 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Portage Lake. Here is what has been measured.
- Eutrophic
- Impaired · Mercury
- 17 ft max depth
- Public access
Portage Lake in Hubbard County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 5.5 ft visibility. Phosphorus: 30.5 µg/L. Chlorophyll-a (algae): 11.2 µg/L. Maximum depth: 17 ft. Surface area: 428.71 acres.
Minnesota DNR's Standard Survey on August 8, 2022 caught 0.89 walleye per gill net at Portage Lake. DNR survey details →
Portage Lake is a 429-acre productive, nutrient-rich eutrophic lake in Hubbard County, Minnesota with a maximum depth of 17 feet (10-foot average). Overall water quality is declining over recent sampling years. The lake supports 12 documented fish species including black bullhead, black crappie, and bluegill. Public access is available with 1 public boat landing. Compared to the 67 other monitored lakes in Hubbard County, Portage Lake ranks #60 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-10-06. Methodology: how these readings are compared.
Portage Lake covers about 430 acres in Hubbard County. It has one public boat landing. The median ice-out date is April 18, which is when the open-water season begins. Vrbo is where to look for cabins and lake homes around Portage Lake, and Booking.com and Expedia search hotels near the lake for your dates.
What Portage Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Fishing12 species recorded
- Ice seasonIce-out around Apr 18
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. Portage Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury, nutrients (phosphorus, nitrogen). Check local advisories before you swim.
Whether Portage 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 Portage Lake
These are the measurements Minnesota PCA publishes for Portage 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 5.5 ft. Phosphorus 30.5 µg/L. Chlorophyll-a 11.2 µg/L. TSI 53.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 5.5ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 30.5µg/L | Fair GoodFairPoor |
| Chlorophyll-a (algae) | 11.2µg/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 Portage Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Portage Lake typically sits around 52°F at the surface in October. Summer average is about 72°F. Usually warmest in Jul (about 75°F) and coldest in Oct (about 52°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (52°F) to its warmest (75°F).
Typical surface water temperature by month, from 475 field readings (2010–2025) via the EPA Water Quality Portal. See the full Portage Lake water temperature breakdown →
Blue-Green Algae (Cyanobacteria)
There’s no recent EPA CyAN cyanobacteria estimate for Portage Lake — clouds, ice, or an off-season gap in coverage. The most recent reading was moderate (36,983 cells/mL) on July 4, 2026.
Blue-green algae can appear and clear within days, so check your state’s current advisory before swimming. EPA CyAN ↗
Minnesota DNR's Standard Survey on August 8, 2022 caught 0.89 walleye per gill net at Portage Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Portage 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
13 surveys on file from MN DNR Fisheries. Most recent: 2022-08-08 (Standard Survey).
13 surveys on file · most recent 2022-08-08 (Standard Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Black Bullhead | 21.92 | 4–15 in 2022-08-08 | 0.38 lb |
| Brown Bullhead | 14.21 | 5–14 in 2022-08-08 | 0.63 lb |
| Bluegill | 11.26 | 3–8 in 2022-08-08 | 0.19 lb |
| Yellow Perch | 7.63 | 5–9 in 2022-08-08 | 0.12 lb |
| Northern Pike | 6.28 | 10–29 in 2022-08-08 | 1.8 lb |
| Black Crappie | 6.06 | 5–12 in 2022-08-08 | 0.34 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.
Black Bullhead
Brown Bullhead
Bluegill
Yellow Perch
From the 2022-08-08 survey
Portage Lake is located three miles northwest of Park Rapids in west-central Hubbard County. Portage has a surface area of 429 acres and a maximum depth of 17 feet. A county owned public access is located on the south shore of the lake. Portage is a very popular lake for ice fishing, as it is one of the first lakes to…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Portage Lake. 4 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — PortageFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Portage (1264)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — PortageFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — PortagePublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
17 ft
Average depth
10 ft
Surface area
429 acres
Shoreline
5.3 mi
Littoral zone
96%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
14 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,417 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Portage 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 Portage Lake
Compare lakeside cabins, hotels, and vacation rentals near Portage Lake in Hubbard 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.
Top-rated places to stay near Portage 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 →
Follow Portage Lake’s readings
Email me when new measurements post for this lake. Updates stay free.
Or email
Fish Species
Click a species to see every lake where it is documented.
Fishing Portage Lake
Water Quality Trend: Worsening
Based on 6 years of monitoring (2020–2025).
Water clarity
Worsening6 years
Phosphorus
Worsening+4.56 µg/L/yr6 years
Chlorophyll-a
Worsening+0.67 µg/L/yr6 years
Ice season
Typical ice-out
Apr 18
Earliest Mar 14, 2024 · Latest May 9, 2013
Typical ice-in
Nov 15
Earliest Oct 31, 1993 · Latest Dec 5, 2009
Most recent ice-out
Mar 14
2024
159 observations · Minnesota PCA ice records
Reservoir Info (USACE NID)
Portage Lake is a man-made reservoir impounded by the Portage Lake (completed 1938), built primarily for recreation on the Portage River; gravity-type dam, 12 ft tall and 11 ft long.
- Surface area
- 422 ac
- Normal storage
- 4,120 ac-ft
- Max storage
- 5,320 ac-ft
- Drainage area
- 4.9 sq mi
- Hazard class
- Low
- Owner
- MNDNR
Source: USACE National Inventory of Dams, NID ID MN00185 · Operator website
EPA Impairment Status
Portage Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).
Causes of impairment
Designated uses not supporting: Fish consumption, Recreation.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN29-0250-00 · Official waterbody report
Nearby Lakes in Hubbard County
Frequently asked questions about Portage Lake
Where is Portage Lake?
- Portage Lake is a lake in Hubbard County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Portage Lake?
- Portage Lake in Hubbard County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 5.5 ft visibility. Phosphorus: 30.5 µg/L. Chlorophyll-a (algae): 11.2 µg/L. Maximum depth: 17 ft. Surface area: 428.71 acres.
Is Portage Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Portage Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury, nutrients (phosphorus, nitrogen). Check local advisories before you swim.
What is the water temperature of Portage Lake?
- Portage Lake typically sits around 52°F at the surface in October, from 475 EPA Water Quality Portal field readings (2010–2025). That is a typical value for the month, not a live reading.
How deep is Portage Lake?
- Portage Lake has a maximum depth of 17 feet and an average depth of 10 feet. The lake covers 428.71 acres.
What fish are in Portage Lake?
- Fish species found in Portage Lake include black bullhead, black crappie, bluegill, brown bullhead, largemouth bass, northern pike, pumpkinseed, rock bass, walleye, white sucker, yellow bullhead, yellow perch. Portage Lake is located in Hubbard County, Minnesota.
What did the DNR fisheries survey find at Portage Lake?
- Minnesota DNR's Standard Survey on August 8, 2022 caught 0.89 walleye per gill net at Portage Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Portage 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 Portage Lake thaw?
- Portage Lake typically has ice-out around Apr 18. Ice typically forms around Nov 15. The open water season is approximately 211 days.
Does Portage Lake have blue-green algae?
- There is no recent EPA CyAN cyanobacteria estimate for Portage Lake (clouds, ice, or an off-season gap). The most recent reading was moderate (36,983 cells/mL). Blue-green algae can appear and clear within days, so check Minnesota's current advisory before swimming.
Are there boat ramps on Portage Lake?
- Portage Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Portage Lake. Public access is listed as yes.
Can I fish at Portage Lake?
- Portage 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 Portage Lake across LakeQuality
Fish species and the cleanest lakes across Minnesota
Fish species and best lakes in Hubbard County
Species activity outlook by water temperature and season
Top lakes and where to stay in the Park Rapids Area area
Where to stay at Minnesota's top lakes, each with its readings
Lakes in the Mississippi Headwaters, ranked by water quality
Minnesota's cleanest lakes, ranked on agency measurements
More lakes in Minnesota
State Parks Near Portage Lake
Other Lakes in Minnesota
Eutrophic Lakes in Minnesota
Compare Portage Lake With Nearby Lakes
Hubbard County · 10.2 ft
Becker County · 8 ft
Hubbard County · 11.5 ft
Hubbard County · 11.2 ft
Hubbard County · 10.5 ft
Hubbard County · 11.2 ft
Where this data comes from
271 measurements from 1 monitoring station, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA271 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Two Reagent Colorimetry
- Phosphorus by Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
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)
Lake details from Minnesota DNR LakeFinder
Named boat-access points from the USGS National Boat Ramps inventory
Ice data from Minnesota DNR Climate