Lake Manawa
Pottawattamie County, IowaView mapDirections
Iowa DNR publishes the water-quality measurements for Lake Manawa. Here is what has been measured.
- Hypereutrophic
- Impaired · Pathogens (E. coli, fecal)
- Public access
Lake Manawa in Pottawattamie County, Iowa has water-quality measurements published by Iowa DNR, shown here as reported. Water clarity: 1 ft visibility. Phosphorus: 110.5 µg/L. Chlorophyll-a (algae): 77 µg/L.
Free interactive depth-contour map of Lake Manawa, reaching a maximum surveyed depth of 21 ft. Toggle Depth contours to overlay the bathymetric survey lines. Contour data from Iowa DNR.
Lake Manawa is a highly nutrient-loaded hypereutrophic lake in Pottawattamie County, Iowa. Water clarity is improving over recent sampling years. Limited fish-species data available. Public access is available with 6 public boat landings. Compared to the 1 other monitored lakes in Pottawattamie County, Lake Manawa ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, Iowa DNR, last sampled 2024-09-30. Methodology: how these readings are compared.
Lake Manawa has 6 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 Lake Manawa, and Booking.com and Expedia search hotels near the lake for your dates.
What Lake Manawa is good for
From access and monitoring records, not editorial picks.
- Boat launch6 documented ramps
Swimming conditions
Readings onlyBacteria advisory
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. Lake Manawa is listed impaired under Clean Water Act §303(d) (IR 5) for pathogens (E. coli, fecal), turbidity. Check local advisories before you swim.
Whether Lake Manawa 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 Lake Manawa
These are the measurements Iowa DNR publishes for Lake Manawa, 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 ft of visibility. Phosphorus 110.5 µg/L. Chlorophyll-a 77 µg/L. TSI 74.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 1ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 111µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 77µg/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. | 74 | Hypereutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Very high nutrients, dense algae, poor clarity
Ask about Lake Manawa
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Lake Manawa typically sits around 72°F at the surface in September. Summer average is about 81°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.
Column height runs from this lake’s coldest month (71°F) to its warmest (84°F).
Typical surface water temperature by month, from 105 field readings (2010–2023) via the EPA Water Quality Portal. See the full Lake Manawa water temperature breakdown →
Recreation & Access
- Lake Manawa State ParkPublic
- Lake Manawa State ParkPublic
- Lake Manawa State ParkPublic
- South Shore DrivePublic
- Council Bluffs Country ClubSemi-private
- Lake Manawa Sailing AssociationSemi-private
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Lake Manawa
Compare lakeside cabins, hotels, and vacation rentals near Lake Manawa in Pottawattamie 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 Lake Manawa are listed below.
Top-rated places to stay near Lake Manawa
Prices for Oct 16–18, 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 Lake Manawa → · more Iowa lake trips
Follow Lake Manawa’s readings
Email me when new measurements post for this lake. Updates stay free.
Or email
Fishing Lake Manawa
Water Quality Trend: Stable
Based on 4 years of monitoring (2021–2024).
Water clarity
Improving4 years
Phosphorus
Stable-1.6 µg/L/yr4 years
Chlorophyll-a
Worsening+30.01 µg/L/yr4 years
EPA Impairment Status
Lake Manawa 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 06-WEM-1711 · Official waterbody report
Regulated Pollution Sources Nearby
10 EPA-permitted facilities operate within about 5 miles of Lake Manawa under Clean Water Act (NPDES) discharge permits, including 2 classified by the EPA as major dischargers. 6 facilities have a reported Clean Water Act violation in the past three years.
- Walter Scott Jr. Energy CenterCouncil Bluffs · 2 mi away · NPDES IA0004308MajorRecent violation
- Council Bluffs City Of StpCouncil Bluffs · 2.7 mi away · NPDES IA0036641MajorRecent violation
- Buckeye Terminals, Llc - Council Bluffs TerminalCouncil Bluffs · 1.5 mi away · NPDES IA0071234Recent violation
- Nustar Council Bluffs TerminalCouncil Bluffs · 1.6 mi away · NPDES IA0046752Recent violation
- Southwest Iowa Renewable EnergyCouncil Bluffs · 2.8 mi away · NPDES IA0081043Recent violation
- Chapters Council Bluffs Opco, Llc (Dba Chapters Living Of Council Bluffs)Council Bluffs · 3.5 mi away · NPDES IA0071269Recent 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 Pottawattamie County
Frequently asked questions about Lake Manawa
Where is Lake Manawa?
- Lake Manawa is a lake in Pottawattamie County, Iowa. Its water-quality measurements are published by Iowa DNR and shown on this page as reported.
What is the water quality of Lake Manawa?
- Lake Manawa in Pottawattamie County, Iowa has water-quality measurements published by Iowa DNR, shown here as reported. Water clarity: 1 ft visibility. Phosphorus: 110.5 µg/L. Chlorophyll-a (algae): 77 µg/L.
Is Lake Manawa safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Lake Manawa is listed impaired under Clean Water Act §303(d) (IR 5) for pathogens (E. coli, fecal), turbidity. Check local advisories before you swim.
What is the water temperature of Lake Manawa?
- Lake Manawa typically sits around 72°F at the surface in September, from 105 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 Lake Manawa?
- Lake Manawa has 6 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Lake Manawa State Park, Lake Manawa State Park, Lake Manawa State Park, South Shore Drive, among others. Public access is listed as yes.
Can I fish at Lake Manawa?
- Lake Manawa has 6 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 Lake Manawa across LakeQuality
More lakes in Iowa
Other Lakes in Iowa
Hypereutrophic Lakes in Iowa
Where this data comes from
48 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_WQX48 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
Impairment status from EPA ATTAINS 303(d) database
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Named boat-access points from the USGS National Boat Ramps inventory