Skip to main content
LakeQuality

Sibley Lake

C
Grade C — Fair
Fair · #76 of 85 lakes in the county · 5.6 ft clear · Eutrophic · 444 acres
Eutrophic

Sibley Lake in Crow Wing County, Minnesota has a water quality grade of C (Fair). Water clarity: 5.6 ft visibility. Phosphorus: 26 µg/L. Chlorophyll-a (algae): 11 µg/L. Maximum depth: 40 ft. Surface area: 444.24 acres.

Clarity
5.6 ft
Typical in August
73°F
Max depth
40 ft
Area
444 acres
Type
Eutrophic
Trend
Improving
Public access
Yes
Ice-out
Apr 17
Open water
217 days

Next lake in Crow Wing County

CMayo Lake4.8 ft clear · Crow Wing CountyView →
Loading map…

Sibley Lake is a 444-acre productive, nutrient-rich eutrophic lake in Crow Wing County, Minnesota with a maximum depth of 40 feet. Water quality is graded C based on 2 sampling years through 2025. Overall water quality is improving over recent sampling years. The lake supports 16 documented fish species including black bullhead, black crappie, and bluegill. Public access is available with 1 public boat landing. Compared to the 84 other monitored lakes in Crow Wing County, Sibley Lake ranks #76 for water quality.

Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-25. Grade methodology: LakeGrade methodology.

Watch Sibley Lake water quality

Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.

Swimming Safety

Grade only

Bacteria B

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.

B
Bacteria swim-safety grade: B
from E. coli testing · 26 samples, 8 seasons

Based on E. coli testing, Sibley Lake rarely exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 3.8% of 26 samples across 8 seasons.

This is a historical summary of past testing, not a current condition — bacteria levels change quickly, especially after rain. Always check Minnesota’s current beach and health-department advisories before swimming.

Compare the safest swimming lakes near Brainerd

Get alerts for Sibley Lake

Water Quality Grade: C (Fair)

Murky, only visible to about 5.6 ft. Phosphorus level: 26 µg/L. Chlorophyll-a: 11 µg/L. Trophic State Index: 53.

MetricValueGrade
Water Clarity (Secchi Depth)5.6 ftNot graded
Phosphorus26 µg/LFair
Chlorophyll-a (Algae)11 µg/LFair
Trophic State Index (TSI)53Eutrophic

High nutrients, frequent algae, reduced clarity

Where to stay near Sibley Lake

Compare lakeside cabins, hotels, and vacation rentals near Sibley Lake in Crow Wing County, Minnesota — 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.

Top-rated places to stay near Sibley Lake

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 Minnesota’s top lakes →

Water Temperature

Sibley Lake typically sits around 73°F at the surface in August. Summer average is about 73°F. Usually warmest in Jul (about 74°F) and coldest in May (about 57°F). These are typical values by month — not a live reading.

Jan
Feb
Mar
Apr
May
57°
Jun
73°
Jul
74°
Aug
73°
Sep
65°
Oct
61°
Nov
Dec

Typical surface water temperature by month, from 27 field readings (20162025) via the EPA Water Quality Portal. See the full Sibley Lake water temperature breakdown →

Lake Details

CharacteristicValue
Maximum Depth40 ft
Surface Area444 acres
Shoreline Length9.1 mi
Littoral Zone57%
Public AccessYes

Lake Size & Watershed

Watershed (drainage) area
54 sq mi
Elevation
1,214 ft

Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).

Recreation & Access

1
Boat Landings
Yes
Public Access
  • Sibley LakePublic

Fish Species

Click a species to see every graded lake where it is documented.

Fishing Sibley Lake

DNR Fisheries Survey Summary

8 surveys on file from MN DNR Fisheries. Most recent: 2021-08-05 (Targeted Survey).

Top Species by Catch Rate

SpeciesAvg CPUEAvg Weight
White Sucker33.641.99 lb
Bluegill26.340.14 lb
CNM24.64
JND17.04
CSH14.000.1 lb
BNS11.57

CPUE = catch per unit effort, averaged across surveys (excludes juvenile shoreline seining). Higher CPUE = more abundant in standardized sampling.

Length Distributions

Number of fish caught at each inch class in the most recent survey that recorded lengths. Red dashed line marks an approximate trophy threshold for that species.

White Sucker

2 fish · 1720 in · 2021-08-05
1017181920

Bluegill

210 fish · 37 in · 2021-08-05
6432034567

From the 2021-08-05 survey

A targeted survey of nearshore fish species in Sibley Lake was conducted on August 5, 2021, by Index of Biological Integrity (IBI) Program staff. Sampling sites were evenly spaced around the lake, and each was sampled by backpack electrofishing and seining with a 50-foot or 15-foot seine, where possible. Backpack…

Source: MN DNR LakeFinder Fisheries Lake Survey

DNR Reports & Resources

Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Sibley Lake. 3 reports on file.

These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).

Based on 6 years of monitoring data (2020-2025).

MetricTrendChange/YearYears
Water Clarity Improving+0.111 m/yr6
Phosphorus Stable-0.31 µg/L/yr6
Chlorophyll-a Improving-0.87 µg/L/yr6
See year-by-year chart →

Ice Season

Historical ice data from Minnesota DNR (19 observations).

Typical Ice-Out
Apr 17
Typical Ice-In
Nov 20

Estimated open water season: 217 days

EarliestLatest
Ice-Out2024-03-12 (2024)2013-05-09 (2013)
Ice-In2019-11-06 (2019)2024-11-30 (2024)

Most recent ice-out: 2024-03-12

Reservoir Info (USACE NID)

Sibley Lake is a man-made reservoir impounded by the Sibley Lake (completed 1937), built primarily for recreation on the MAYO CREEK - TR; gravity-type dam, 8 ft tall and 41 ft long.

Surface area
418 ac
Normal storage
10,200 ac-ft
Max storage
11,730 ac-ft
Drainage area
55 sq mi
Hazard class
Undetermined
Owner
MNDNR

Source: USACE National Inventory of Dams, NID ID MN00045 · Operator website

EPA Impairment Status

Sibley Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).

Causes of impairment

Impaired biota (cause unknown)Nutrients (phosphorus, nitrogen)

A Total Maximum Daily Load (TMDL) plan has been approved.

Source: EPA ATTAINS assessment unit MN18-0404-00 · Official waterbody report

County Ranking

Ranked #76 of 85 lakes in Crow Wing County

Nearby Lakes With Higher Grades

Sibley Lake holds Grade C. 3 nearby lakes hold higher nutrient-and-algae grades — useful for a swim day, not a reason to skip lodging here.

See full comparison →

Nearby Lakes in Crow Wing County

Frequently asked questions about Sibley Lake

What is the water quality grade for Sibley Lake?

Sibley Lake in Crow Wing County, Minnesota has a water quality grade of C (Fair). Water clarity: 5.6 ft visibility. Phosphorus: 26 µg/L. Chlorophyll-a (algae): 11 µg/L. Maximum depth: 40 ft. Surface area: 444.24 acres.

Is Sibley Lake safe to swim in?

Based on E. coli testing, Sibley Lake rarely exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 3.8% of 26 samples across 8 seasons. That works out to a bacteria swim-safety grade of B — a historical summary of past testing, not a current reading. Sibley Lake has a water quality grade of C (Fair). Bacteria levels can spike quickly after heavy rain, so always check Minnesota's current beach and health-department advisories before you swim.

What is the water temperature of Sibley Lake?

Sibley Lake typically sits around 73°F at the surface in August, from 27 EPA Water Quality Portal field readings (2016–2025). That is a typical value for the month, not a live reading.

How deep is Sibley Lake?

Sibley Lake has a maximum depth of 40 feet. The lake covers 444.24 acres.

What fish are in Sibley Lake?

Fish species found in Sibley Lake include black bullhead, black crappie, bluegill, bowfin (dogfish), brown bullhead, common carp, green sunfish, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, rock bass, walleye, white sucker, yellow bullhead, yellow perch. Sibley Lake is located in Crow Wing County, Minnesota.

When does Sibley Lake thaw?

Sibley Lake typically has ice-out around Apr 17. Ice typically forms around Nov 20. The open water season is approximately 217 days.

Are there boat ramps on Sibley Lake?

Sibley Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Sibley Lake. Public access is listed as yes.

Eutrophic Lakes in Minnesota

Where this data comes from

161 measurements from 3 monitoring stations, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.

Collected and reported by

  • Minnesota Pollution Control Agency - Ambient Surface WaterMNPCA161 samples · 2020–2025

Analytical methods

  • Field measurement/observation, generic method
  • Phosphorus by Two Reagent Colorimetry
  • 10200 H 2 ~ Chlorophyll a-b-c Determination by spectrophotometer
Monitoring station identifiers (3)

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

Lake size & watershed from HydroLAKES (HydroSHEDS)

Lake details from Minnesota DNR LakeFinder

Named boat-access points from the USGS National Boat Ramps inventory

Ice data from Minnesota DNR Climate