Roberts Creek Lake
Marion County, Iowa296 acresView mapDirections
Iowa DNR publishes the water-quality measurements for Roberts Creek Lake. Here is what has been measured.
- Hypereutrophic
- Impaired · Turbidity
- 46 ft max depth
- Public access
Roberts Creek Lake in Marion County, Iowa has water-quality measurements published by Iowa DNR, shown here as reported. Water clarity: 1.5 ft visibility. Phosphorus: 115 µg/L. Chlorophyll-a (algae): 44.6 µg/L. Surface area: 296 acres.
Free interactive depth-contour map of Roberts Creek Lake, reaching a maximum surveyed depth of 20 ft. Toggle Depth contours to overlay the bathymetric survey lines. Contour data from Iowa DNR.
Roberts Creek Lake is a 296-acre highly nutrient-loaded hypereutrophic lake in Marion County, Iowa with an estimated average depth of about 46 feet. Overall water quality is improving over recent sampling years. Limited fish-species data available. Public access is available.
Source: EPA Water Quality Portal sampling records, Iowa DNR, last sampled 2024-09-17. Methodology: how these readings are compared.
What Roberts Creek Lake is good for
From access and monitoring records, not editorial picks.
- Camping4 public campgrounds nearby
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. Roberts Creek Lake is listed impaired under Clean Water Act §303(d) (IR 5) for turbidity. Check local advisories before you swim.
Whether Roberts Creek 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 Roberts Creek Lake
These are the measurements Iowa DNR publishes for Roberts Creek 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 1.5 ft of visibility. Phosphorus 115 µg/L. Chlorophyll-a 44.6 µg/L. TSI 71.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 1.5ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 115µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 44.6µg/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. | 71 | Hypereutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Very high nutrients, dense algae, poor clarity
Ask about Roberts Creek Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Roberts Creek Lake typically sits around 69°F at the surface in September. Summer average is about 78°F. Usually warmest in Jul (about 80°F) and coldest in Sep (about 69°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (69°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 Roberts Creek Lake water temperature breakdown →
Lake Details
Max depth
~46 ft est.
Surface area
296 acres
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 Roberts Creek Lake.
Lake Size & Watershed
Watershed (drainage) area
13 sq mi
HydroLAKES / HydroSHEDS
Shoreline
5 mi
HydroLAKES / HydroSHEDS
Elevation
735 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
Public campgrounds near Roberts Creek Lake
- Roberts Creek East Campground0.7 km
- Roberts Creek West Campground0.8 km
- Fifield (ia)1.7 kmReserve
- Whitebreast Point Shelter (ia)3.3 kmReserve
Nearest public campgrounds in the USGS National Map inventory, within about 3 miles. An empty list means USGS records no campground that close, which is not the same as camping being unavailable. Where the source gives an official reservation link, it is used; the cabin and hotel search does not cover campsites. More camping lakes
Stays via Stay22
Stays near Roberts Creek Lake
Compare lakeside cabins, hotels, and vacation rentals near Roberts Creek Lake in Marion 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 Roberts Creek Lake are listed below.
Top-rated places to stay near Roberts Creek Lake
Prices for Oct 23–25, 4 adults. Change dates on the map below.
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Planning a trip? Cabins and lodging at Roberts Creek Lake → · more Iowa lake trips
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Fishing Roberts Creek Lake
Water Quality Trend: Improving
Based on 5 years of monitoring (2020–2024).
Water clarity
Improving5 years
Phosphorus
Worsening+14 µg/L/yr4 years
Chlorophyll-a
Improving-11.27 µg/L/yr5 years
Reservoir Info (USACE NID)
Roberts Creek Lake is a man-made reservoir impounded by the Roberts Creek Dam (completed 1968), built primarily for recreation on the Roberts Creek; earth-type dam, 60 ft tall and 2,400 ft long.
- Surface area
- 296 ac
- Normal storage
- 3,043 ac-ft
- Max storage
- 21,863 ac-ft
- Drainage area
- 13.28 sq mi
- Hazard class
- Significant
- Owner
- Marion County Board of Supervisors
All listed purposes: Recreation;Other.
Source: USACE National Inventory of Dams, NID ID IA00655 · Operator website
EPA Impairment Status
Roberts Creek Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Designated uses not supporting: Recreation.
Source: EPA ATTAINS assessment unit IA 04-LDM-1019 · Official waterbody report
Regulated Pollution Sources Nearby
3 EPA-permitted facilities operate within about 5 miles of Roberts Creek Lake under Clean Water Act (NPDES) discharge permits. 2 facilities have a reported Clean Water Act violation in the past three years.
- Park Hills Wastewater FacilityOtley · 1.4 mi away · NPDES IA0075434Recent violation
- Lake Red Rock - Whitebreast Sewage LagoonKnoxville · 3.1 mi away · NPDES IA0083402Recent violation
- Lake Red Rock - North Overlook Sewage LagoonKnoxville · 4.9 mi away · NPDES IA0083399
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 Marion County
Frequently asked questions about Roberts Creek Lake
Where is Roberts Creek Lake?
- Roberts Creek Lake is a lake in Marion County, Iowa. Its water-quality measurements are published by Iowa DNR and shown on this page as reported.
What is the water quality of Roberts Creek Lake?
- Roberts Creek Lake in Marion County, Iowa has water-quality measurements published by Iowa DNR, shown here as reported. Water clarity: 1.5 ft visibility. Phosphorus: 115 µg/L. Chlorophyll-a (algae): 44.6 µg/L. Surface area: 296 acres.
Is Roberts Creek Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Roberts Creek Lake is listed impaired under Clean Water Act §303(d) (IR 5) for turbidity. Check local advisories before you swim.
What is the water temperature of Roberts Creek Lake?
- Roberts Creek Lake typically sits around 69°F at the surface in September, from 29 EPA Water Quality Portal field readings (2010–2023). That is a typical value for the month, not a live reading.
How deep is Roberts Creek Lake?
- No published bathymetric survey covers Roberts Creek Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 46 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate. The lake covers 296 acres.
Can I fish at Roberts Creek Lake?
- Public access to Roberts Creek 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.
Are there campgrounds on Roberts Creek Lake?
- Roberts Creek Lake has 4 public campgrounds from USGS The National Map within 5 km, including Roberts Creek East Campground, Roberts Creek West Campground, Fifield (ia), Whitebreast Point Shelter (ia). This is a location join, not a booking. Cabins and hotels are listed separately; campsite reservations use the official link when the source provides one.
Explore Roberts Creek Lake across LakeQuality
Depth, room, public access, and the state wake-sport rules
Species activity outlook by water temperature and season
Where to stay at Iowa's top lakes, each with its readings
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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
Impairment status from EPA ATTAINS 303(d) database
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Lake size & watershed from HydroLAKES (HydroSHEDS)
Public campgrounds from USGS The National Map Structures, within about 3 miles