Skip to main content
LakeQuality

Sibley Lake

C
Grade C — Fair
Fair · #1 of 2 lakes in the county · Eutrophic · 2,176 acres
Limited DataEutrophic

Sibley Lake in Natchitoches Parish County, Louisiana has a water quality grade of C (Fair). Phosphorus: 50 µg/L. Surface area: 2176 acres.

Area
2,176 acres
Type
Eutrophic
Public access
Yes

Next lake in Natchitoches Parish County

Swipe

DNantachie Creek Southeast of Montgomery LakeGrant Parish CountyView →
Loading map…

Sibley Lake is a 2,176-acre productive, nutrient-rich eutrophic lake in Natchitoches Parish County, Louisiana. Water quality is graded C based on 1 sampling years through 2024. Limited fish-species data available. Public access is available with 2 public boat landings. Compared to the 1 other monitored lakes in Natchitoches Parish County, Sibley Lake ranks #1 for water quality.

Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2024-05-08. Grade methodology: LakeGrade methodology.

Watch Sibley Lake water quality

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

Swimming Safety

Grade only

Limited 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.

Generally safe for swimming, moderate water quality

Get alerts for Sibley Lake

Water Quality Grade: C (Fair)

No clarity data. Phosphorus level: 50 µg/L. Trophic State Index: 61.

MetricValueGrade
Water Clarity (Secchi Depth)No recent samples
Phosphorus50 µg/LFair
Chlorophyll-a (Algae)No recent samples
Trophic State Index (TSI)61Eutrophic

High nutrients, frequent algae, reduced clarity

Where to stay near Sibley Lake

Compare lakeside cabins, hotels, and vacation rentals near Sibley Lake in Natchitoches Parish County, Louisiana — 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.

Lake Details

CharacteristicValue
Surface Area2,176 acres
Public AccessYes

No bathymetric survey has been published for Sibley Lake, so its depth is not documented here.

Recreation & Access

2
Boat Landings
Yes
Public Access
  • Oak GrovePublic
  • Settle's Boat LandingSemi-private

Named access points from the USGS National Boat Ramps inventory, snapped within 5 km. More lakes with boat ramps

Fishing Sibley Lake

Reservoir Info (USACE NID)

Sibley Lake is a man-made reservoir impounded by the Sibley Lake Dam (completed 1962), built primarily for water supply on the Youngs Bayou; earth-type dam, 36 ft tall and 6,045 ft long.

Surface area
2,176 ac
Normal storage
19,500 ac-ft
Max storage
56,700 ac-ft
Drainage area
40 sq mi
Hazard class
High
Owner
City of Natchitoches

Source: USACE National Inventory of Dams, NID ID LA00027 · 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

Temperature

Source: EPA ATTAINS assessment unit LA101001_00 · Official waterbody report

County Ranking

Ranked #1 of 2 lakes in Natchitoches Parish County

Nearby Lakes in Natchitoches Parish County

Frequently asked questions about Sibley Lake

Where is Sibley Lake?

Sibley Lake is a lake in Natchitoches Parish County, Louisiana. LakeQuality grades it C for nutrients and algae. The letter is not a swimming clearance.

What is the water quality grade for Sibley Lake?

Sibley Lake in Natchitoches Parish County, Louisiana has a water quality grade of C (Fair). Phosphorus: 50 µg/L. Surface area: 2176 acres.

Is Sibley Lake safe to swim in?

Generally safe for swimming, moderate water quality. Sibley Lake has a water quality grade of C (Fair). Always check local health department advisories before swimming.

Are there boat ramps on Sibley Lake?

Sibley Lake has 2 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Oak Grove, Settle's Boat Landing. Public access is listed as yes.

Where this data comes from

35 measurements from 1 monitoring station, 2020–2024. Retrieved from the EPA Water Quality Portal on 2026-08-21.

Collected and reported by

  • LDEQ/Water Planning and Assessment (Louisiana)LADEQWPD_WQX35 samples · 2020–2024

Analytical methods

  • Total Phosphorus After Block Digestion
  • 2130 B ~ Nephelometric Method
  • 2120 B ~ Color in Water by Visual Comparison
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

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