Ellis Lake
Lucas County, Iowa80 acresView mapDirections
Nutrients and algae run well above the regional average.
- Hypereutrophic
- Impaired · Oxygen depletion (low DO)
- #1 of 4 in the county
- 31 ft max depth
- Public access
- Limited data
Ellis Lake in Lucas County, Iowa has a water quality grade of F (Algae-prone). Water clarity: 2 ft visibility. Phosphorus: 63.5 µg/L. Chlorophyll-a (algae): 35.6 µg/L. Surface area: 80 acres.
- Clarity
- 2 ft
- Typical in September
- 77°F
- Max depth
- ~31 ft est.
- Area
- 80 acres
- Type
- Hypereutrophic
- Trend
- ↑ Improving
- Public access
- Yes
Stays via Stay22
Stays near Ellis Lake
Compare lakeside cabins, hotels, and vacation rentals near Ellis Lake in Lucas 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 grade measures nutrients and algae, not lodging — cabins and rentals around Ellis Lake are listed below.
Top-rated places to stay near Ellis Lake
Prices for Sep 11–13, 4 adults. Change dates on the map below.
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Watch Ellis Lake’s letter
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Free interactive depth-contour map of Ellis Lake, reaching a maximum surveyed depth of 20 ft. Toggle Depth contours to overlay the bathymetric survey lines. Contour data from Iowa DNR.
Ellis Lake is a 80-acre highly nutrient-loaded hypereutrophic lake in Lucas County, Iowa with an estimated average depth of about 31 feet. Water quality is graded F based on 2 sampling years through 2022. Overall water quality is improving over recent sampling years. Limited fish-species data available. Public access is available with 1 public boat landing. Compared to the 3 other monitored lakes in Lucas County, Ellis Lake ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, Iowa DNR, last sampled 2022-09-06. Grade methodology: LakeQuality methodology.
What Ellis Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
Swimming Safety
Grade onlyLimited data
Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
The F is nutrients and algae, not a swimming clearance. Ellis Lake is listed impaired under Clean Water Act §303(d) (IR 5) for oxygen depletion (low DO). Check local advisories before you swim.
Water Quality Grade: F (Algae-prone)
Very murky, less than 2 ft of visibility. Phosphorus 63.5 µg/L. Chlorophyll-a 35.6 µg/L. TSI 66. The letter is not a swimming clearance.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 2 ft | Not graded |
| Phosphorus | 63.5 µg/L | Poor |
| Chlorophyll-a (Algae) | 35.6 µg/L | Poor |
| Trophic State Index (TSI) | 66 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
Water Temperature
Ellis Lake typically sits around 77°F at the surface in September. Summer average is about 84°F. Usually warmest in Jul (about 84°F) and coldest in May (about 71°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 9 field readings (2018–2022) via the EPA Water Quality Portal. See the full Ellis Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | ~31 ft est. |
| Average Depth | ~14 ft est. |
| Surface Area | 80 acres |
| Public Access | Yes |
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Iowa has not published bathymetry for Ellis 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
- Lake EllisPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Fishing Ellis Lake
Water Quality Trend: ↑ Improving
Based on 5 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.128 m/yr | 5 |
| Phosphorus | → Stable | +0.36 µg/L/yr | 5 |
| Chlorophyll-a | ↑ Improving | -4.14 µg/L/yr | 5 |
Reservoir Info (USACE NID)
Ellis Lake is a man-made reservoir impounded by the Lake Ellis Dam (completed 1993), built primarily for water supply on the TR-LITTLE WHITEBREAST CREEK; earth-type dam, 38 ft tall and 900 ft long.
- Surface area
- 80 ac
- Normal storage
- 803 ac-ft
- Max storage
- 1,463 ac-ft
- Drainage area
- 2.9 sq mi
- Hazard class
- Significant
- Owner
- Chariton Municipal Utilities
All listed purposes: Water Supply;Recreation.
Source: USACE National Inventory of Dams, NID ID IA01358 · Operator website
EPA Impairment Status
Ellis Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Source: EPA ATTAINS assessment unit IA 04-LDM-1071 · Official waterbody report · Matched by proximity (1.06 km)
Regulated Pollution Sources Nearby
1 EPA-permitted facility operate within about 5 miles of Ellis Lake under Clean Water Act (NPDES) discharge permits.
- Chariton Municipal Water WorksChariton · 0.2 mi away · NPDES IA0081825
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.
County Ranking
Ranked #1 of 4 lakes in Lucas County
Nearby Lakes With Higher Grades
Ellis Lake holds Grade F. One nearby lake has a higher nutrient-and-algae grade — useful for a swim day, not a reason to skip lodging here.
Nearby Lakes in Lucas County
Frequently asked questions about Ellis Lake
Where is Ellis Lake?
- Ellis Lake is a lake in Lucas County, Iowa. LakeQuality grades it F for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Ellis Lake?
- Ellis Lake in Lucas County, Iowa has a water quality grade of F (Algae-prone). Water clarity: 2 ft visibility. Phosphorus: 63.5 µg/L. Chlorophyll-a (algae): 35.6 µg/L. Surface area: 80 acres.
Is Ellis Lake safe to swim in?
- The F is nutrients and algae, not a swimming clearance. Ellis Lake is listed impaired under Clean Water Act §303(d) (IR 5) for oxygen depletion (low DO). Check local advisories before you swim.
What is the water temperature of Ellis Lake?
- Ellis Lake typically sits around 77°F at the surface in September, from 9 EPA Water Quality Portal field readings (2018–2022). That is a typical value for the month, not a live reading.
How deep is Ellis Lake?
- No published bathymetric survey covers Ellis Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 31 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 80 acres.
Are there boat ramps on Ellis Lake?
- Ellis Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Lake Ellis. Public access is listed as yes.
Explore Ellis Lake across LakeQuality
More Iowa Lake Rankings
Other Grade F Lakes in Iowa
Hypereutrophic Lakes in Iowa
Where this data comes from
36 measurements from 1 monitoring station, 2020–2022. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Iowa DNR Surface Water Monitoring Data
21IOWA_WQX36 samples · 2020–2022
Analytical methods
- Unknown
- Phosphorus by Colorimetry
- 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
- ISU modification of APHA 2130-B
Monitoring station identifiers (1)
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
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