City Millpond
City Millpond in Green Lake County, Wisconsin is not rated for water quality — its monitoring record does not meet the evidence bar. Phosphorus: 38.4 µg/L. Maximum depth: 236 ft. Surface area: 7920 acres.
Wisconsin DNR lists Smallmouth Bass as common on City Millpond. DNR survey details →
- Max depth
- 236 ft
- Area
- 7,920 acres
- Public access
- Yes
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Why City Millpond has no grade
We grade a lake only when the monitoring record supports a letter: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For City Millpond, no nutrient or algae measurement meets the evidence bar (at least 3 samples within 10 years). Sampling here has recorded phosphorus, but not water clarity and algae (chlorophyll-a).
Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.
Sampling is run by WI DNR and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
City Millpond is a 7,920-acre lake in Green Lake County, Wisconsin with a maximum depth of 236 feet. The lake supports 7 documented fish species including Panfish, Largemouth Bass, and Smallmouth Bass. Public access is available with 2 public boat landings and 3 public beaches.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2024-06-05. Grade methodology: LakeQuality methodology.
Watch City Millpond water quality
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Swimming Safety
Not ratedBacteria B
Based on E. coli testing, City Millpond rarely exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 3.1% of 98 samples across 9 seasons.
This is a historical summary of past testing, not a current condition — bacteria levels change quickly, especially after rain. Always check Wisconsin’s current beach and health-department advisories before swimming.
Water quality measurements for City Millpond
These readings exist but are not enough for an A–F grade — see why.
No clarity data. Phosphorus level: 38.4 µg/L. Trophic State Index: 57.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | 38.4 µg/L | Not graded |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 57 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near City Millpond
Compare lakeside cabins, hotels, and vacation rentals near City Millpond in Green Lake County, Wisconsin — 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 City Millpond
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Planning a trip? Cabins and lodging at City Millpond → · more Wisconsin lake trips
Wisconsin DNR lists Smallmouth Bass as common on City Millpond.
A DNR fisheries survey reports fish abundance and catch rates, not a water-quality grade. LakeQuality does not assign an A–F grade on City Millpond — official chemistry is on file, not a letter. 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. 85 stations on file (most recent sample 2026).
Fish Species (DNR-rated)
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 236 ft |
| Surface Area | 7,920 acres |
| Public Access | Yes |
Recreation & Access
- Canal StreetPublic
- Hattie Sherwood ParkPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Fish Species
Click a species to see every graded lake where it is documented.
Fishing City Millpond
Invasive & Introduced Species
Red chips are ecologically harmful invasive species. Gray chips are stocked or introduced fish that aren't a current ecological concern.
Reservoir Info (USACE NID)
City Millpond is a man-made reservoir impounded by the Upper Green Lake (completed 1869), built primarily for recreation on the PUCHYAN; gravity-type dam, 8 ft tall and 200 ft long.
- Surface area
- 7,346 ac
- Normal storage
- 30,000 ac-ft
- Max storage
- 40,000 ac-ft
- Drainage area
- 115 sq mi
- Hazard class
- High
- Owner
- City Of Green Lake
Source: USACE National Inventory of Dams, NID ID WI00633 · Operator website · Matched by proximity (0.46 km)
Graded lakes near City Millpond
City Millpond has no grade, but these lakes within a short drive do.
Nearby Lakes in Green Lake County
Frequently asked questions about City Millpond
Where is City Millpond?
- City Millpond is a lake in Green Lake County, Wisconsin. LakeQuality has not rated this lake (UNRATED) — there is not enough recent sampling to assign a letter.
What is the water quality grade for City Millpond?
- City Millpond in Green Lake County, Wisconsin is not rated for water quality — its monitoring record does not meet the evidence bar. Phosphorus: 38.4 µg/L. Maximum depth: 236 ft. Surface area: 7920 acres.
Is City Millpond safe to swim in?
- Based on E. coli testing, City Millpond rarely exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 3.1% of 98 samples across 9 seasons. That works out to a bacteria swim-safety grade of B — a historical summary of past testing, not a current reading. City Millpond is not rated for water quality — its monitoring record does not meet the evidence bar. Bacteria levels can spike quickly after heavy rain, so always check Wisconsin's current beach and health-department advisories before you swim.
How deep is City Millpond?
- City Millpond has a maximum depth of 236 feet. The lake covers 7920 acres.
What fish are in City Millpond?
- Fish species found in City Millpond include Panfish, Largemouth Bass, Smallmouth Bass, Northern Pike, Trout, Walleye, Catfish. City Millpond is located in Green Lake County, Wisconsin.
What did the DNR fisheries survey find at City Millpond?
- Wisconsin DNR lists Smallmouth Bass as common on City Millpond. A DNR fisheries survey reports fish abundance and catch rates, not a water-quality grade. LakeQuality does not assign an A–F grade on City Millpond — official chemistry is on file, not a letter. Catch rate is not a swim clearance and is not a weekly bite report.
Are there boat ramps on City Millpond?
- City Millpond has 2 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Canal Street, Hattie Sherwood Park. Public access is listed as yes.
Explore City Millpond across LakeQuality
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Where this data comes from
7 measurements from 1 monitoring station, 2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Wisconsin Department of Natural Resources
WIDNR_WQX7 samples · 2024
Analytical methods
- Phosphorus by Colorimetry
Monitoring station identifiers (1)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.
Other records on this page
Lake size & watershed from HydroLAKES (HydroSHEDS)
Fish and recreation data from Wisconsin DNR Lakes
Named boat-access points from the USGS National Boat Ramps inventory