Lake Sidney Lanier
Forsyth County, GeorgiaView mapDirections
Georgia EPD publishes the water-quality measurements for Lake Sidney Lanier. Here is what has been measured.
- Eutrophic
- Impaired · Algal growth
- Public access
Lake Sidney Lanier in Forsyth County, Georgia has water-quality measurements published by Georgia EPD, shown here as reported. Water clarity: 9.2 ft visibility. Phosphorus: 20 µg/L. Chlorophyll-a (algae): 7.7 µg/L.
Lake Sidney Lanier is a productive, nutrient-rich eutrophic lake in Forsyth County, Georgia. Overall water quality is declining over recent sampling years. Limited fish-species data available. Public access is available with 7 public boat landings. Compared to the 2 other monitored lakes in Forsyth County, Lake Sidney Lanier ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, Georgia EPD, last sampled 2025-10-07. Methodology: how these readings are compared.
Lake Sidney Lanier has 7 public boat landings, so a lakefront rental is not the only way to get a boat on the water. If you are planning to stay, you can search lake houses and cabins around Lake Sidney Lanier on Vrbo, or look for a hotel room near the lake on Booking.com or Expedia.
What Lake Sidney Lanier is good for
From access and monitoring records, not editorial picks.
- Boat launch7 documented ramps
- Camping1 public campground nearby
Swimming conditions
Readings onlyRecreation use not supported
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 Sidney Lanier is listed impaired under Clean Water Act §303(d) (IR 5) for algal growth, pCBs. Check local advisories before you swim.
Whether Lake Sidney Lanier is safe to swim in today is a call for the Georgia Environmental Protection Division and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Lake Sidney Lanier
These are the measurements Georgia EPD publishes for Lake Sidney Lanier, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Moderate clarity, visible to about 9.2 ft. Phosphorus 20 µg/L. Chlorophyll-a 7.7 µg/L. TSI 48.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 9.2ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 20µg/L | Fair GoodFairPoor |
| Chlorophyll-a (algae) | 7.7µg/L | Fair GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 48 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Lake Sidney Lanier
Answers come straight from the public measurements and survey records on this page.
→ Lake Sidney Lanier water level: the live USGS gauge reading
Recreation & Access
- Old FederalPublic
- Old Federal Day UsePublic
- Vanns TavernPublic
- Commodore Drive - 1Public
- Commodore Drive - 2Public
- Sunrise Cove MarinaSemi-private
Showing 6 of 7 documented landings from the USGS National Boat Ramps inventory.
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Public campgrounds near Lake Sidney Lanier
- Old Federal2.4 kmReserve
Nearest public campgrounds in the USGS National Map inventory, within about 3 miles. An empty list means USGS records no campground that close, which is not the same as camping being unavailable. Where the source gives an official reservation link, it is used; the cabin and hotel search does not cover campsites. More camping lakes
Stays via Stay22
Stays near Lake Sidney Lanier
Compare lakeside cabins, hotels, and vacation rentals near Lake Sidney Lanier in Forsyth County, Georgia — 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 Lake Sidney Lanier
Prices for Oct 30–Nov 1, 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 Sidney Lanier → · more Georgia lake trips
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Fishing Lake Sidney Lanier
Water Quality Trend: Worsening
Based on 14 years of monitoring (2012–2025).
Water clarity
Stable14 years
Phosphorus
Stable0 µg/L/yr6 years
Chlorophyll-a
Worsening+0.55 µg/L/yr14 years
EPA Impairment Status
Lake Sidney Lanier 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: Drinking water, Aquatic life, Recreation.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit GAR031300010819 · Official waterbody report
Nearby Lakes in Forsyth County
Frequently asked questions about Lake Sidney Lanier
Where is Lake Sidney Lanier?
- Lake Sidney Lanier is a lake in Forsyth County, Georgia. Its water-quality measurements are published by Georgia EPD and shown on this page as reported.
What is the water quality of Lake Sidney Lanier?
- Lake Sidney Lanier in Forsyth County, Georgia has water-quality measurements published by Georgia EPD, shown here as reported. Water clarity: 9.2 ft visibility. Phosphorus: 20 µg/L. Chlorophyll-a (algae): 7.7 µg/L.
Is Lake Sidney Lanier safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Lake Sidney Lanier is listed impaired under Clean Water Act §303(d) (IR 5) for algal growth, pCBs. Check local advisories before you swim.
Are there boat ramps on Lake Sidney Lanier?
- Lake Sidney Lanier has 7 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Old Federal, Old Federal Day Use, Vanns Tavern, Commodore Drive - 1, among others. Public access is listed as yes.
Can I fish at Lake Sidney Lanier?
- Lake Sidney Lanier has 7 documented boat landings in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Georgia's fish and wildlife agency, so check its current regulations before you go.
Are there campgrounds on Lake Sidney Lanier?
- Lake Sidney Lanier has 1 public campground from USGS The National Map within 5 km, including Old Federal. This is a location join, not a booking. Cabins and hotels are listed separately; campsite reservations use the official link when the source provides one.
Explore Lake Sidney Lanier across LakeQuality
7.2 mi away · cable-pulled, no boat wake
Species activity outlook by water temperature and season
Where to stay at Georgia's top lakes, each with its readings
Georgia's cleanest lakes, ranked on agency measurements
Planning a trip around Chattahoochee River?
Lake Sidney Lanier is about 26 miles from Chattahoochee River National Recreation Area. Crowds there swing hard by season, so the month you pick changes both how busy the park is and what lodging costs.
Best time to visit Chattahoochee River →More lakes in Georgia
Other Lakes in Georgia
Eutrophic Lakes in Georgia
Where this data comes from
900 measurements from 4 monitoring stations, 2012–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Georgia DNR Environmental Protection Division
21GAEPD_WQX900 samples · 2012–2025
Analytical methods
- Phosphorus by Colorimetry
- 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
- Turbidity by Nephelometry
Monitoring station identifiers (4)
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
Named boat-access points from the USGS National Boat Ramps inventory
Public campgrounds from USGS The National Map Structures, within about 3 miles