Silver Lake
Palo Alto County, IowaView mapDirections
Iowa DNR publishes the water-quality measurements for Silver Lake. Here is what has been measured.
- Hypereutrophic
- Impaired · Algal growth
- 51 ft max depth
- Public access
Silver Lake in Palo Alto County, Iowa has water-quality measurements published by Iowa DNR, shown here as reported. Water clarity: 1.2 ft visibility. Phosphorus: 209 µg/L. Chlorophyll-a (algae): 53.9 µg/L.
Free interactive depth-contour map of Silver Lake, reaching a maximum surveyed depth of 6 ft. Toggle Depth contours to overlay the bathymetric survey lines. Contour data from Iowa DNR.
Silver Lake is a highly nutrient-loaded hypereutrophic lake in Palo Alto County, Iowa with an estimated average depth of about 51 feet. Overall water quality is declining over recent sampling years. Limited fish-species data available. Public access is available with 1 public boat landing. Compared to the 2 other monitored lakes in Palo Alto County, Silver Lake ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, Iowa DNR, last sampled 2024-09-11. Methodology: how these readings are compared.
What Silver Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
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. Silver Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for algal growth, turbidity. Check local advisories before you swim.
Whether Silver Lake is safe to swim in today is a call for the Iowa Department of Natural Resources and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Silver Lake
These are the measurements Iowa DNR publishes for Silver 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 1.2 ft of visibility. Phosphorus 209 µg/L. Chlorophyll-a 53.9 µg/L. TSI 75.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 1.2ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 209µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 53.9µg/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. | 75 | Hypereutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Very high nutrients, dense algae, poor clarity
Ask about Silver Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Silver Lake typically sits around 70°F at the surface in September. Summer average is about 75°F. Usually warmest in Jul (about 80°F) and coldest in Jun (about 70°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (70°F) to its warmest (80°F).
Typical surface water temperature by month, from 27 field readings (2010–2023) via the EPA Water Quality Portal. See the full Silver Lake water temperature breakdown →
Lake Details
Max depth
~51 ft est.
Public access
Yes
Listed by Iowa DNR
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Iowa has not published bathymetry for Silver Lake.
Lake Size & Watershed
Watershed (drainage) area
14 sq mi
HydroLAKES / HydroSHEDS
Surface area
672 acres
HydroLAKES / HydroSHEDS
Shoreline
5.9 mi
HydroLAKES / HydroSHEDS
Elevation
1,312 ft
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
- Silver Lake - Palo AltoPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Silver Lake
Compare lakeside cabins, hotels, and vacation rentals near Silver Lake in Palo Alto County, Iowa — 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 Silver Lake are listed below.
Top-rated places to stay near Silver Lake
Prices for Oct 23–25, 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 trip? Cabins and lodging at Silver Lake → · more Iowa lake trips
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Fishing Silver Lake
Water Quality Trend: Worsening
Based on 5 years of monitoring (2020–2024).
Water clarity
Worsening5 years
Phosphorus
Worsening+59.3 µg/L/yr4 years
Chlorophyll-a
Improving-17.53 µg/L/yr5 years
EPA Impairment Status
Silver 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: Recreation.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit IA 04-UDM-1229 · Official waterbody report
Regulated Pollution Sources Nearby
2 EPA-permitted facilities operate within about 5 miles of Silver Lake under Clean Water Act (NPDES) discharge permits. 1 facility has a reported Clean Water Act violation in the past three years.
- Ayrshire, City Of StpAyrshire · 2.9 mi away · NPDES IA0079677Recent violation
- Ayrshire, City Of WtpAyrshire · 2.5 mi away · NPDES IA0084361
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 Palo Alto County
Frequently asked questions about Silver Lake
Where is Silver Lake?
- Silver Lake is a lake in Palo Alto County, Iowa. Its water-quality measurements are published by Iowa DNR and shown on this page as reported.
What is the water quality of Silver Lake?
- Silver Lake in Palo Alto County, Iowa has water-quality measurements published by Iowa DNR, shown here as reported. Water clarity: 1.2 ft visibility. Phosphorus: 209 µg/L. Chlorophyll-a (algae): 53.9 µg/L.
Is Silver Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Silver Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for algal growth, turbidity. Check local advisories before you swim.
What is the water temperature of Silver Lake?
- Silver Lake typically sits around 70°F at the surface in September, from 27 EPA Water Quality Portal field readings (2010–2023). That is a typical value for the month, not a live reading.
How deep is Silver Lake?
- No published bathymetric survey covers Silver Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 51 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 Silver Lake?
- Silver Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Silver Lake - Palo Alto. Public access is listed as yes.
Can I fish at Silver Lake?
- Silver 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 Iowa's fish and wildlife agency, so check its current regulations before you go.
Explore Silver Lake across LakeQuality
More lakes in Iowa
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Hypereutrophic Lakes in Iowa
Where this data comes from
52 measurements from 1 monitoring station, 2020–2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Iowa DNR Surface Water Monitoring Data
21IOWA_WQX52 samples · 2020–2024
Analytical methods
- Unknown
- Phosphorus by Colorimetry
- 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
- In-Vitro Determination of Chlorophyll
- ISU modification of APHA 2130-B
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
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