Grant County Lake Quality

Washington, 13 lakes, average grade B (Good)

Grant County has 13 graded lakes — a thin enough sample that one or two stressed lakes can move the county average noticeably. Use the per-lake pages below for what actually matters. The county-wide average lands at B — solid water quality with most lakes carrying clear summer transparency and low-to-moderate phosphorus.

Most of the county's monitored lakes are shallow — under 50 feet — which means wind keeps the water column mixed all summer and sediment-bound phosphorus releases back into the surface layer whenever the bottom is disturbed. Banks Lake (A) is the cleanest in the county.

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Quick Answers for Grant County

Cleanest lakes in Grant County →Cleanest lakes in Washington →Safest swimming lakes in Washington →

Planning a trip? Check special fishing regulations for Banks Lake — or check the official Washington fishing regulations.

All Lakes in Grant County

Rank	Lake	Grade	Clarity	Phosphorus
1	Banks Lake	A	19.4 ft	13 µg/L
2	Fdr Lake	A	28.2 ft	-
3	Billy Clapp Lake	A	16.4 ft	-
4	Nla Lake	A	12.8 ft	15.7 µg/L
5	Moses Lake	B	-	20 µg/L
6	Nla Lake	B	16.4 ft	39517.1 µg/L
7	Nla Lake	C	12.1 ft	69000 µg/L
8	Nla Lake	C	11.6 ft	20000 µg/L
9	Brook Lake	D	-	80 µg/L
10	Nla Lake	D	2.2 ft	99000 µg/L
11	Nla Lake	F	1.1 ft	174.6 µg/L