Study Ranks Hartwell Lake Third Cleanest Lake in U.S.

Observer Reports

Hartwell Lake has landed in some very good company. In a recent Fishbox study shared with Travel + Leisure, the Georgia-South Carolina reservoir was ranked the third-cleanest lake in the United States, behind Lake Superior and Lake Chelan, and ahead of Lake of the Ozarks and Lake Pend Oreille.

“It’s an honor to be recognized as one of the ‘Top 10 Cleanest Lakes in America,’” said Neil Paul, executive director of Visit Anderson. “I believe the success of this recognition can be tied directly to the continued management efforts of the U.S. Army Corps of Engineers and the South Carolina Department of Natural Resources. Locally, the standard for improved conservation efforts set by Anderson County, Green Pond Landing and Visit Anderson, and the support we have received from the angling community have served instrumental to this recognition.”

Fishbox examined 100 large lakes using data on dissolved oxygen, ammonia, lead, sulfate, phosphorus, turbidity, and related measures collected between Jan. 1, 2020, and July 15, 2025, from the National Water Quality Monitoring Council. Nearly half of the lakes studied had at least three pollution factors, which made Hartwell’s high ranking stand out all the more.

Here is the full top 10 list from the study:

1. Lake Superior — Michigan, Minnesota, Wisconsin, Ontario.

2. Lake Chelan — Washington.

3. Hartwell Lake — Georgia, South Carolina.

4. Lake of the Ozarks — Missouri.

5. Lake Pend Oreille — Idaho.

6. Lake Winnibigoshish — Minnesota.

7. Kentucky Lake — Kentucky, Tennessee.

8. Lake Norman — North Carolina.

9. Lake Mead — Arizona, Nevada.

10. Flathead Lake — Montana.