Martha Lake
Wright County, Minnesota102 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Martha Lake. Here is what has been measured.
- Eutrophic
- 22 ft max depth
- Public access
Martha Lake in Wright County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 3 ft visibility. Phosphorus: 77.5 µg/L. Chlorophyll-a (algae): 68.1 µg/L. Maximum depth: 22 ft. Surface area: 102.45 acres.
Minnesota DNR's Standard Survey on June 13, 2022 caught 0.33 walleye per gill net at Martha Lake. DNR survey details →
Martha Lake is a 102-acre productive, nutrient-rich eutrophic lake in Wright County, Minnesota with a maximum depth of 22 feet (8-foot average). Overall water quality is declining over recent sampling years. The lake supports 9 documented fish species including black crappie, bluegill, and brown bullhead. Public access is available with 1 public boat landing. Compared to the 50 other monitored lakes in Wright County, Martha Lake ranks #38 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-29. Methodology: how these readings are compared.
What Martha Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Fishing9 species recorded
- Ice seasonIce-out around Apr 9
Swimming conditions
Readings onlyAlgae risk
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. Check local advisories before you swim.
Whether Martha 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 Martha Lake
These are the measurements Minnesota PCA publishes for Martha Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Very murky, less than 3 ft of visibility. Phosphorus 77.5 µg/L. Chlorophyll-a 68.1 µg/L. TSI 67.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 3ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 77.5µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 68.1µg/L | Poor GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 67 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Martha Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Martha Lake typically sits around 64°F at the surface in October. Summer average is about 74°F. Usually warmest in Jul (about 76°F) and coldest in May (about 61°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (61°F) to its warmest (76°F).
Typical surface water temperature by month, from 188 field readings (2011–2025) via the EPA Water Quality Portal. See the full Martha Lake water temperature breakdown →
Minnesota DNR's Standard Survey on June 13, 2022 caught 0.33 walleye per gill net at Martha Lake.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Martha 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
6 surveys on file from MN DNR Fisheries. Most recent: 2022-06-13 (Standard Survey).
6 surveys on file · most recent 2022-06-13 (Standard Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Black Bullhead | 184.85 | 12 in 2006-06-12 | 0.41 lb |
| Bluegill | 34.85 | 4–8 in 2022-06-13 | 0.18 lb |
| Black Crappie | 32.36 | 5–11 in 2022-06-13 | 0.19 lb |
| Largemouth Bass | 29.15 | 4–20 in 2022-06-13 | 0.92 lb |
| Pumpkinseed | 22.74 | 6 in 2022-06-13 | 0.13 lb |
| Hybrid Sunfish | 14.30 | 6–8 in 2022-06-13 | 0.21 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
Bluegill
Black Crappie
Largemouth Bass
From the 2022-06-13 survey
Lake Martha is a small 97-acre lake located two miles southwest of Hanover in Wright County. Martha has a maximum depth of 25 feet and an average water clarity of six feet. A state-owned public access is located along the south shore and offers parking for two to three vehicle/trailer combos. A standard survey was…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Martha Lake. 3 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — MarthaFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Martha (2024)Aquatic Plant Report · MN DNR LakeFinder
- —Public Water Access Sites — MarthaPublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
22 ft
Average depth
7.9 ft
Surface area
102 acres
Shoreline
1.9 mi
Littoral zone
70%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
1 sq mi
HydroLAKES / HydroSHEDS
Elevation
958 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Lake MarthaPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Martha Lake
Compare lakeside cabins, hotels, and vacation rentals near Martha Lake in Wright 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 Martha Lake are listed below.
Top-rated places to stay near Martha 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 Martha Lake’s readings
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Fish Species
Click a species to see every lake where it is documented.
Fishing Martha Lake
Water Quality Trend: Worsening
Based on 6 years of monitoring (2020–2025).
Water clarity
Worsening6 years
Phosphorus
Worsening+7.19 µg/L/yr6 years
Chlorophyll-a
Worsening+4.52 µg/L/yr6 years
Ice season
Typical ice-out
Apr 9
Earliest Mar 13, 2016 · Latest Apr 21, 2008
Typical ice-in
Nov 30
Earliest Nov 4, 1991 · Latest Dec 20, 1998
Most recent ice-out
Mar 13
2016
14 observations · Minnesota PCA ice records
Nearby Lakes in Wright County
Frequently asked questions about Martha Lake
Where is Martha Lake?
- Martha Lake is a lake in Wright County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Martha Lake?
- Martha Lake in Wright County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 3 ft visibility. Phosphorus: 77.5 µg/L. Chlorophyll-a (algae): 68.1 µg/L. Maximum depth: 22 ft. Surface area: 102.45 acres.
Is Martha Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
What is the water temperature of Martha Lake?
- Martha Lake typically sits around 64°F at the surface in October, from 188 EPA Water Quality Portal field readings (2011–2025). That is a typical value for the month, not a live reading.
How deep is Martha Lake?
- Martha Lake has a maximum depth of 22 feet and an average depth of 7.9 feet. The lake covers 102.45 acres.
What fish are in Martha Lake?
- Fish species found in Martha Lake include black crappie, bluegill, brown bullhead, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, walleye, yellow bullhead. Martha Lake is located in Wright County, Minnesota.
What did the DNR fisheries survey find at Martha Lake?
- Minnesota DNR's Standard Survey on June 13, 2022 caught 0.33 walleye per gill net at Martha Lake. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Martha 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 Martha Lake thaw?
- Martha Lake typically has ice-out around Apr 9. Ice typically forms around Nov 30. The open water season is approximately 235 days.
Are there boat ramps on Martha Lake?
- Martha Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Lake Martha. Public access is listed as yes.
Can I fish at Martha Lake?
- Martha 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 Martha Lake across LakeQuality
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Fish species and best lakes in Wright County
Species activity outlook by water temperature and season
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Where this data comes from
187 measurements from 2 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
MNPCA187 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Two Reagent Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
Monitoring station identifiers (2)
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
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