What is the cleanest lake in Delaware County, Oklahoma?

Grand Lake in Delaware County is the highest-rated lake in Delaware County, Oklahoma with an EPA water quality grade of D and 1.6 feet of water clarity.

How are these rankings calculated?

Lakes are graded A through F on nutrients and algae — total phosphorus, nitrogen, chlorophyll-a, and turbidity — against EPA National Lakes Assessment 2022 condition classes for that lake’s ecoregion. Water clarity (Secchi depth) is measured and shown; it is not the letter. Lakes without enough recent samples are UNRATED, not given an F. Source data comes from the EPA Water Quality Portal.

Cleanest Lakes in Delaware County, Oklahoma

Grand Lake in Delaware County leads the rankings with a water quality grade of D and 1.6 ft of clarity. Below are the top 3 cleanest monitored lakes in Delaware County, Oklahoma, ranked by EPA water quality score.

Ranked List

#	Lake	County	Grade	Clarity	Phosphorus	Algae
1	Grand Lake	Delaware	D	1.6 ft	720 µg/L	-
2	Lake O the Cherokees	Delaware	NR	-	-	-
3	Lake Eucha	Delaware	NR	-	-	-

Ranked List

More Answers for Delaware County, Oklahoma