North Lake
Cass County, Missouri28 acresView mapDirections
Nutrients and algae run well above the regional average.
- Hypereutrophic
- Impaired · Algal growth
- #1 of 4 in the county
- 25 ft max depth
- Public access
North Lake in Cass County, Missouri has a water quality grade of F (Algae-prone). Water clarity: 1.6 ft visibility. Phosphorus: 152 µg/L. Chlorophyll-a (algae): 60.3 µg/L. Surface area: 28 acres.
- Clarity
- 1.6 ft
- Typical in August
- 83°F
- Max depth
- ~25 ft est.
- Area
- 28 acres
- Type
- Hypereutrophic
- Phosphorus
- 152 µg/L
- Chlorophyll-a
- 60.3 µg/L
- Trend
- → Stable
- Public access
- Yes
Stays via Stay22
Stays near North Lake
Compare lakeside cabins, hotels, and vacation rentals near North Lake in Cass County, Missouri — 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 North Lake are listed below.
Top-rated places to stay near North Lake
Prices for Sep 11–13, 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 whole trip? See where to stay at Missouri’s top lakes →
Watch North Lake’s letter
Email me if this lake’s grade moves. Grades stay free.
Or email
North Lake is a 28-acre highly nutrient-loaded hypereutrophic lake in Cass County, Missouri with an estimated average depth of about 25 feet. Water quality is graded F based on 2 sampling years through 2024. Water clarity is declining 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 Cass County, North Lake ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, Missouri DNR, last sampled 2024-08-06. Grade methodology: LakeQuality methodology.
What North Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
Swimming Safety
Grade onlyAlgae risk
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. North Lake is listed impaired under Clean Water Act §303(d) (IR 5) for algal growth. Check local advisories before you swim.
Water Quality Grade: F (Algae-prone)
Very murky, less than 1.6 ft of visibility. Phosphorus 152 µg/L. Chlorophyll-a 60.3 µg/L. TSI 73. The letter is not a swimming clearance.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.6 ft | Not graded |
| Phosphorus | 152 µg/L | Poor |
| Chlorophyll-a (Algae) | 60.3 µg/L | Poor |
| Trophic State Index (TSI) | 73 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
Water Temperature
North Lake typically sits around 83°F at the surface in August. Summer average is about 83°F. Usually warmest in Jul (about 85°F) and coldest in May (about 73°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 58 field readings (2010–2024) via the EPA Water Quality Portal. See the full North Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | ~25 ft est. |
| Average Depth | ~9 ft est. |
| Surface Area | 28 acres |
| Public Access | Yes |
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Missouri has not published bathymetry for North 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
- North Lake (Harrisonville)Public
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Fishing North Lake
Water Quality Trend: → Stable
Based on 5 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↓ Declining | -0.047 m/yr | 4 |
| Phosphorus | ↑ Improving | -3.59 µg/L/yr | 5 |
| Chlorophyll-a | → Stable | +0.76 µg/L/yr | 5 |
Reservoir Info (USACE NID)
North Lake is a man-made reservoir impounded by the North Lake Dam (completed 1955), built primarily for recreation on the TR-POLECAT CREEK; earth-type dam, 28 ft tall.
- Surface area
- 28 ac
- Normal storage
- 233 ac-ft
- Max storage
- 419 ac-ft
- Drainage area
- 1,280 sq mi
- Hazard class
- Low
- Owner
- CITY OF HARRISONVILLE
All listed purposes: Recreation;Water Supply.
Source: USACE National Inventory of Dams, NID ID MO20078 · Operator website
EPA Impairment Status
North Lake is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).
Causes of impairment
Source: EPA ATTAINS assessment unit MO_7218.00 · Official waterbody report
Regulated Pollution Sources Nearby
1 EPA-permitted facility operate within about 5 miles of North Lake under Clean Water Act (NPDES) discharge permits. 1 facility has a reported Clean Water Act violation in the past three years.
- Peculiar WwtpPeculiar · 4.1 mi away · NPDES MO0089443Recent 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.
County Ranking
Ranked #1 of 4 lakes in Cass County
Nearby Lakes in Cass County
Frequently asked questions about North Lake
Where is North Lake?
- North Lake is a lake in Cass County, Missouri. LakeQuality grades it F for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for North Lake?
- North Lake in Cass County, Missouri has a water quality grade of F (Algae-prone). Water clarity: 1.6 ft visibility. Phosphorus: 152 µg/L. Chlorophyll-a (algae): 60.3 µg/L. Surface area: 28 acres.
Is North Lake safe to swim in?
- The F is nutrients and algae, not a swimming clearance. North Lake is listed impaired under Clean Water Act §303(d) (IR 5) for algal growth. Check local advisories before you swim.
What is the water temperature of North Lake?
- North Lake typically sits around 83°F at the surface in August, from 58 EPA Water Quality Portal field readings (2010–2024). That is a typical value for the month, not a live reading.
How deep is North Lake?
- No published bathymetric survey covers North Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 25 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 28 acres.
Are there boat ramps on North Lake?
- North Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include North Lake (Harrisonville). Public access is listed as yes.
Explore North Lake across LakeQuality
Species activity outlook by water temperature and season
Where to stay at Missouri's top lakes, each with its grade
Very high nutrients, dense algae, poor clarity
Missouri's cleanest and most-polluted lakes, ranked
More Missouri Lake Rankings
Other Grade F Lakes in Missouri
Hypereutrophic Lakes in Missouri
Where this data comes from
85 measurements from 2 monitoring stations, 2020–2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Univ. of Missouri, Columbia
UMC84 samples · 2020–2024 - Missouri Dept. of Natural Resources
MDNR1 sample · 2023
Analytical methods
- Depth, Secchi disk in meters
- 4500 P E ~ Phosphorus in Water by Colorimetry- Ascorbic Acid Method
- 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
- Nitrogen and Phosphorus, Total, Whole-water, Alkaline Persulfate Digest
Monitoring station identifiers (2)
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