Arrowhead Lake
Sac County, Iowa110 acresView mapDirections
Iowa DNR publishes the water-quality measurements for Arrowhead Lake. Here is what has been measured.
- Eutrophic
- Public access
Arrowhead Lake in Sac County, Iowa has water-quality measurements published by Iowa DNR, shown here as reported. Water clarity: 5.6 ft visibility. Phosphorus: 26 µg/L. Chlorophyll-a (algae): 7.1 µg/L. Surface area: 110 acres.
Free interactive depth-contour map of Arrowhead Lake, reaching a maximum surveyed depth of 22 ft. Toggle Depth contours to overlay the bathymetric survey lines. Contour data from Iowa DNR.
Arrowhead Lake is a 110-acre productive, nutrient-rich eutrophic lake in Sac County, Iowa. Overall water quality is improving over recent sampling years. Limited fish-species data available. Public access is available with 2 public boat landings. Compared to the 1 other monitored lakes in Sac County, Arrowhead Lake ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, Iowa DNR, last sampled 2024-09-04. Methodology: how these readings are compared.
Arrowhead Lake covers about 110 acres in Sac County. It has 2 public boat landings, so a lakefront rental is not the only way to get a boat on the water. Vrbo is where to look for cabins and lake homes around Arrowhead Lake, and Booking.com and Expedia search hotels near the lake for your dates.
What Arrowhead Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch2 documented ramps
Swimming conditions
Readings onlyLow algae
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 Arrowhead 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 Arrowhead Lake
These are the measurements Iowa DNR publishes for Arrowhead Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Murky, only visible to about 5.6 ft. Phosphorus 26 µg/L. Chlorophyll-a 7.1 µg/L. TSI 51.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 5.6ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 26µg/L | Good GoodFairPoor |
| Chlorophyll-a (algae) | 7.1µg/L | Good GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 51 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Arrowhead Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Arrowhead Lake typically sits around 79°F at the surface in August. Summer average is about 78°F. Usually warmest in Jul (about 80°F) and coldest in May (about 64°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (64°F) to its warmest (80°F).
Typical surface water temperature by month, from 29 field readings (2010–2023) via the EPA Water Quality Portal. See the full Arrowhead Lake water temperature breakdown →
Lake Details
Surface area
110 acres
Public access
Yes
Listed by Iowa DNR
No bathymetric survey has been published for Arrowhead Lake, so its depth is not documented here.
Recreation & Access
- Black Hawk Wildlife AreaPublic
- Black Hawk Wildlife AreaPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Arrowhead Lake
Compare lakeside cabins, hotels, and vacation rentals near Arrowhead Lake in Sac 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.
Top-rated places to stay near Arrowhead Lake
Prices for Oct 30–Nov 1, 4 adults. Change dates on the map below.
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Fishing Arrowhead Lake
Water Quality Trend: Improving
Based on 5 years of monitoring (2020–2024).
Water clarity
Stable5 years
Phosphorus
Improving-10.3 µg/L/yr4 years
Chlorophyll-a
Improving-4.99 µg/L/yr5 years
Reservoir Info (USACE NID)
Arrowhead Lake is a man-made reservoir impounded by the Provost Bay Dam, built primarily for other on the unnamed tributary; earth-type dam, 10 ft tall and 650 ft long.
- Surface area
- 110 ac
- Max storage
- 257 ac-ft
- Drainage area
- 0.54 sq mi
- Hazard class
- Low
- Owner
- Iowa Department of Natural Resources
Source: USACE National Inventory of Dams, NID ID IA04396 · Operator website · Matched by proximity (0.67 km)
Regulated Pollution Sources Nearby
3 EPA-permitted facilities operate within about 5 miles of Arrowhead Lake under Clean Water Act (NPDES) discharge permits. 3 facilities have a reported Clean Water Act violation in the past three years.
- Lake View City Of StpLake View · 1.1 mi away · NPDES IA0041998Recent violation
- Wall Lake City Of StpWall Lake · 3.1 mi away · NPDES IA0033065Recent violation
- Western Iowa Energy, LlcWall Lake · 3.5 mi away · NPDES IA0079855Recent violation
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 Sac County
Frequently asked questions about Arrowhead Lake
Where is Arrowhead Lake?
- Arrowhead Lake is a lake in Sac County, Iowa. Its water-quality measurements are published by Iowa DNR and shown on this page as reported.
What is the water quality of Arrowhead Lake?
- Arrowhead Lake in Sac County, Iowa has water-quality measurements published by Iowa DNR, shown here as reported. Water clarity: 5.6 ft visibility. Phosphorus: 26 µg/L. Chlorophyll-a (algae): 7.1 µg/L. Surface area: 110 acres.
Is Arrowhead 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 Arrowhead Lake?
- Arrowhead Lake typically sits around 79°F at the surface in August, from 29 EPA Water Quality Portal field readings (2010–2023). That is a typical value for the month, not a live reading.
Are there boat ramps on Arrowhead Lake?
- Arrowhead Lake has 2 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Black Hawk Wildlife Area, Black Hawk Wildlife Area. Public access is listed as yes.
Can I fish at Arrowhead Lake?
- Arrowhead Lake has 2 documented boat landings 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 Arrowhead Lake across LakeQuality
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Where this data comes from
60 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_WQX60 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
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Named boat-access points from the USGS National Boat Ramps inventory