Poplar Lake
Poplar Lake in Polk County, Wisconsin is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 12.7 ft visibility.
- Clarity
- 12.7 ft
- Max depth
- ~23 ft est.
- Trend
- → Stable
- Public access
- Yes
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Why Poplar Lake 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 Poplar Lake, the only measurement available is water clarity, which is not a water-quality indicator on its own — EPA's National Lakes Assessment does not grade clarity. Sampling here has recorded water clarity, but not phosphorus 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.
Poplar Lake is a lake in Polk County, Wisconsin with an estimated average depth of about 23 feet. Limited fish-species data available. Public access is available with 1 public boat landing.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water, last sampled 2024-08-14. Grade methodology: LakeQuality methodology.
Watch Poplar Lake water quality
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Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Poplar Lake
These readings exist but are not enough for an A–F grade — see why.
Good clarity, visible to about 12.7 ft. Trophic State Index: 40.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 12.7 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 40 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near Poplar Lake
Compare lakeside cabins, hotels, and vacation rentals near Poplar Lake in Polk 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 Poplar Lake
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Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | ~23 ft est. |
| Average Depth | ~11 ft est. |
| Public Access | Yes |
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Wisconsin has not published bathymetry for Poplar Lake.
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS). Mean depth here is modelled, not surveyed — HydroLAKES v1.0 estimates lake depth from surrounding terrain rather than from soundings. Treat it as an approximation, and prefer a state bathymetric survey where one exists.
Recreation & Access
- Poplar LakePublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Fishing Poplar Lake
Water Quality Trend: → Stable
Based on 4 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | → Stable | -0.163 m/yr | 4 |
Regulated Pollution Sources Nearby
4 EPA-permitted facilities operate within about 5 miles of Poplar Lake under Clean Water Act (NPDES) discharge permits. 2 facilities have a reported Clean Water Act violation in the past three years.
- St Croix Falls City OfSt Croix Falls · 2.7 mi away · NPDES WI0020796Recent violation
- Wi Dnr St Croix Falls HatcherySt Croix Falls · 3.5 mi away · NPDES WI0004201Recent violation
- Saputo Cheese Usa Inc DresserDresser · 1.5 mi away · NPDES WI0054852
- Taylors Falls WwtfTaylors Falls · 4.8 mi away · NPDES MN0053309
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.
Graded lakes near Poplar Lake
Poplar Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Polk County
Frequently asked questions about Poplar Lake
Where is Poplar Lake?
- Poplar Lake is a lake in Polk 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 Poplar Lake?
- Poplar Lake in Polk County, Wisconsin is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 12.7 ft visibility.
Is Poplar Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Poplar Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
How deep is Poplar Lake?
- No published bathymetric survey covers Poplar Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 23 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate.
Are there boat ramps on Poplar Lake?
- Poplar Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Poplar Lake. Public access is listed as yes.
Explore Poplar Lake across LakeQuality
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Where this data comes from
5 measurements from 2 monitoring stations, 2020–2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Wisconsin Department of Natural Resources
WIDNR_WQX5 samples · 2020–2024
Monitoring station identifiers (2)
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
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Lake size & watershed from HydroLAKES (HydroSHEDS)
Named boat-access points from the USGS National Boat Ramps inventory