Springbrook Lake
Guthrie County, Iowa12 acresView mapDirections
Iowa DNR publishes the water-quality measurements for Springbrook Lake. Here is what has been measured.
- Eutrophic
- Public access
Springbrook Lake in Guthrie County, Iowa has water-quality measurements published by Iowa DNR, shown here as reported. Water clarity: 3 ft visibility. Phosphorus: 59 µg/L. Chlorophyll-a (algae): 22.9 µg/L. Surface area: 12 acres.
Free interactive depth-contour map of Springbrook Lake, reaching a maximum surveyed depth of 20 ft. Toggle Depth contours to overlay the bathymetric survey lines. Contour data from Iowa DNR.
Springbrook Lake is a 12-acre productive, nutrient-rich eutrophic lake in Guthrie County, Iowa. Overall water quality is declining over recent sampling years. Limited fish-species data available. Public access is available.
Source: EPA Water Quality Portal sampling records, Iowa DNR, last sampled 2024-09-04. Methodology: how these readings are compared.
Swimming conditions
Readings onlyBacteria tested: exceedances
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.
Based on E. coli testing, Springbrook Lake frequently exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 20% of 5 samples across 2 seasons.
This is a historical summary of past testing, not a current condition — bacteria levels change quickly, especially after rain. Always check Iowa’s current beach and health-department advisories before swimming.
Whether Springbrook 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 Springbrook Lake
These are the measurements Iowa DNR publishes for Springbrook 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 3 ft of visibility. Phosphorus 59 µg/L. Chlorophyll-a 22.9 µg/L. TSI 62.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 3ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 59µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 22.9µg/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. | 62 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Springbrook Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Springbrook Lake typically sits around 68°F at the surface in September. Summer average is about 78°F. Usually warmest in Jul (about 81°F) and coldest in Sep (about 68°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (68°F) to its warmest (81°F).
Typical surface water temperature by month, from 100 field readings (2010–2023) via the EPA Water Quality Portal. See the full Springbrook Lake water temperature breakdown →
Lake Details
Surface area
12 acres
Public access
Yes
Listed by Iowa DNR
No bathymetric survey has been published for Springbrook Lake, so its depth is not documented here.
Stays via Stay22
Stays near Springbrook Lake
Compare lakeside cabins, hotels, and vacation rentals near Springbrook Lake in Guthrie 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 Springbrook Lake are listed below.
Top-rated places to stay near Springbrook Lake
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Fishing Springbrook Lake
Water Quality Trend: Worsening
Based on 4 years of monitoring (2021–2024).
Water clarity
Improving4 years
Phosphorus
Worsening+69.9 µg/L/yr4 years
Chlorophyll-a
Worsening+7.46 µg/L/yr4 years
Reservoir Info (USACE NID)
Springbrook Lake is a man-made reservoir impounded by the Springbrook Lake Dam (completed 1934), built primarily for recreation on the TR-MIDDLE RACCOON RIVER; earth-type dam, 40 ft tall and 580 ft long.
- Surface area
- 12 ac
- Normal storage
- 58 ac-ft
- Max storage
- 187 ac-ft
- Drainage area
- 2.54 sq mi
- Hazard class
- Significant
- Owner
- Iowa Department of Natural Resources
Source: USACE National Inventory of Dams, NID ID IA01345 · Operator website
Regulated Pollution Sources Nearby
2 EPA-permitted facilities operate within about 5 miles of Springbrook Lake under Clean Water Act (NPDES) discharge permits.
- Dnr Springbrook State Park-Campground AreaGuthrie Center · 0.3 mi away · NPDES IA0075281
- Dnr Springbrook State ParkGuthrie Center · 0.7 mi away · NPDES IA0075272
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 Guthrie County
Frequently asked questions about Springbrook Lake
Where is Springbrook Lake?
- Springbrook Lake is a lake in Guthrie County, Iowa. Its water-quality measurements are published by Iowa DNR and shown on this page as reported.
What is the water quality of Springbrook Lake?
- Springbrook Lake in Guthrie County, Iowa has water-quality measurements published by Iowa DNR, shown here as reported. Water clarity: 3 ft visibility. Phosphorus: 59 µg/L. Chlorophyll-a (algae): 22.9 µg/L. Surface area: 12 acres.
Is Springbrook Lake safe to swim in?
- Based on E. coli testing, Springbrook Lake frequently exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 20% of 5 samples across 2 seasons. That is a historical summary of past bacteria testing, not a current reading and not a swimming clearance. Bacteria levels can spike quickly after heavy rain, so whether Springbrook Lake is safe to swim in today is a call for Iowa's water agency and the county health department; check their current beach advisories before you swim.
What is the water temperature of Springbrook Lake?
- Springbrook Lake typically sits around 68°F at the surface in September, from 100 EPA Water Quality Portal field readings (2010–2023). That is a typical value for the month, not a live reading.
Can I fish at Springbrook Lake?
- Public access to Springbrook Lake is listed as yes on the lake record. 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 Springbrook Lake across LakeQuality
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Where this data comes from
54 measurements from 1 monitoring station, 2021–2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Iowa DNR Surface Water Monitoring Data
21IOWA_WQX54 samples · 2021–2024
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)