Gage Lake
Cass County, MichiganView mapDirections
EGLE publishes the water-quality measurements for Gage Lake. Here is what has been measured.
- Eutrophic
Gage Lake in Cass County, Michigan has water-quality measurements published by EGLE, shown here as reported. Phosphorus: 60 µg/L.
Gage Lake is a productive, nutrient-rich eutrophic lake in Cass County, Michigan. Overall water quality is declining over recent sampling years. Compared to the 9 other monitored lakes in Cass County, Gage Lake ranks #9 for water quality.
Source: EPA Water Quality Portal sampling records, EGLE, last sampled 2025-10-20. Methodology: how these readings are compared.
Swimming conditions
Readings onlyElevated nutrients
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 Gage Lake is safe to swim in today is a call for the Michigan Department of Environment, Great Lakes, and Energy (EGLE) and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Gage Lake
These are the measurements EGLE publishes for Gage Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
No clarity data. Phosphorus 60 µg/L. TSI 63.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | No reading How deep a black-and-white disk stays visible from the surface. Higher is clearer. | |
| Total phosphorus | 60µg/L | Poor GoodFairPoor |
| 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. | 63 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Gage Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Gage Lake typically sits around 58°F at the surface in October. Summer average is about 71°F. Usually warmest in Aug (about 73°F) and coldest in Feb (about 39°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (39°F) to its warmest (73°F).
Typical surface water temperature by month, from 775 field readings (2013–2025) via the EPA Water Quality Portal. See the full Gage Lake water temperature breakdown →
Stays via Stay22
Stays near Gage Lake
Compare lakeside cabins, hotels, and vacation rentals near Gage Lake in Cass County, Michigan — 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 Gage Lake are listed below.
Top-rated places to stay near Gage Lake
Prices for Oct 30–Nov 1, 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 Michigan’s top lakes →
Follow Gage Lake’s readings
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Fishing Gage Lake
Water Quality Trend: Worsening
Based on 9 years of monitoring (2016–2025).
Phosphorus
Worsening+17.14 µg/L/yr9 years
Regulated Pollution Sources Nearby
3 EPA-permitted facilities operate within about 5 miles of Gage Lake under Clean Water Act (NPDES) discharge permits, including 1 classified by the EPA as major discharger. 2 facilities have a reported Clean Water Act violation in the past three years.
- Dowagiac WwtpDowagiac · 4.2 mi away · NPDES MI0022837MajorRecent violation
- Alliance Cloud Services Llc-GwcuDowagiac · 2.5 mi away · NPDES MI0003069Recent violation
- Service Oil Co-DowagiacDowagiac · 3.8 mi away · NPDES MI0054488
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 Cass County
Frequently asked questions about Gage Lake
Where is Gage Lake?
- Gage Lake is a lake in Cass County, Michigan. Its water-quality measurements are published by EGLE and shown on this page as reported.
What is the water quality of Gage Lake?
- Gage Lake in Cass County, Michigan has water-quality measurements published by EGLE, shown here as reported. Phosphorus: 60 µg/L.
Is Gage 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 Gage Lake?
- Gage Lake typically sits around 58°F at the surface in October, from 775 EPA Water Quality Portal field readings (2013–2025). That is a typical value for the month, not a live reading.
Explore Gage Lake across LakeQuality
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Where this data comes from
424 measurements from 1 monitoring station, 2016–2025. Retrieved from the EPA Water Quality Portal on 2026-08-26.
Collected and reported by
- Pokagon Band of Potawatomi Indians, Michigan and Indiana (Tribal)
PBDNR424 samples · 2016–2025
Analytical methods
- 4500 P B ~ Phosphorus, sample preparation method
- 4500 P ~ Phosphorus in water and wastewater
- Total Phosphorus After Block Digestion
- Turbidity by Nephelometry
- Direct Measurement Method
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
Regulated discharger data from EPA ECHO (ICIS-NPDES)