Washington Soil Drainage Rankings

Washington

How well does the soil drain across Washington? We ranked every USDA survey area by the percentage of land classified as "well drained." Areas at the top of the list have soils where water moves through at a healthy rate — favorable for building, septic, and gardening. Areas at the bottom have more waterlogged or slowly-draining soils that may require engineered solutions.

The best-drained survey area is Umatilla National Forest, Washington at 99% well-drained soils. The most drainage-challenged is Bangor Naval Station, Washington at 0%.

#	Survey Area	Well Drained	Poorly Drained	Dominant Class
1	Umatilla National Forest, Washington	99%	0%	Well drained
2	Garfield County Area, Washington	99%	0%	Well drained
3	Adams County, Washington	97%	1%	Well drained
4	Yakima Training Center, Parts of Kittitas and Yakima Counties, Washington	97%	0%	Well drained
5	North Cascades National Park Complex, Washington	96%	1%	Well drained
6	Mount Baker-Snoqualmie National Forest, Washington	96%	0%	Well drained
7	Columbia County Area, Washington	96%	0%	Well drained
8	Olympic National Park, Washington	96%	0%	Well drained
9	Lincoln County, Washington	95%	1%	Well drained
10	Yakama Nation Closed Area, Washington, Parts of Klickitat and Yakima Counties	95%	3%	Well drained
11	Chelan County Area, Washington (Parts of Chelan and Kittitas Counties)	94%	0%	Well drained
12	Klickitat County Area, Washington	94%	2%	Well drained
13	Yakima County Area, Washington	91%	3%	Well drained
14	Cashmere Mountain Area, Washington, Parts of Chelan and Okanogan Counties	91%	0%	Well drained
15	North Ferry Area, Washington	90%	2%	Well drained
16	Asotin County Area, Washington (Asotin and Garfield Counties)	89%	0%	Well drained
17	Douglas County, Washington	88%	1%	Well drained
18	Pend Oreille County Area, Washington	88%	5%	Well drained
19	Skamania County Area, Washington	88%	0%	Well drained
20	Okanogan County Area, Washington	88%	2%	Well drained
21	Wenatchee National Forest, Naches Area, Washington, Parts of Kittitas and Yakima Counties	87%	2%	Well drained
22	Walla Walla County Area, Washington	87%	1%	Well drained
23	Colville Indian Reservation (Parts of Ferry and Okanogan Counties), Washington	87%	2%	Well drained
24	Whitman County, Washington	86%	5%	Well drained
25	Cowlitz County, Washington	85%	5%	Well drained
26	Stevens County, Washington	85%	4%	Well drained
27	Okanogan National Forest Area, Washington	84%	1%	Well drained
28	Kittitas County Area, Washington	81%	4%	Well drained
29	Spokane County, Washington	81%	6%	Well drained
30	Benton County Area, Washington	80%	1%	Well drained
31	Grays Harbor County Area, Pacific and Wahkiakum Counties, Washington	79%	9%	Well drained
32	Lewis County Area, Washington	78%	10%	Well drained
33	Mount Rainier National Park, Washington	76%	12%	Well drained
34	Clark County, Washington	74%	9%	Well drained
35	Olympic National Forest Area, Washington (Parts of Clallam, Grays Harbor, Jefferson, and Mason Counties)	73%	5%	Well drained
36	Franklin County, Washington	72%	0%	Well drained
37	Snoqualmie Pass Area, Washington (Parts of King and Pierce Counties)	69%	3%	Well drained
38	Grant County, Washington	64%	2%	Well drained
39	Yakima Nation Irrigated Area, Washington, Part of Yakima County	59%	30%	Well drained
40	Hanford Atomic Energy Reservation, Washington	56%	0%	Well drained
41	San Juan County, Washington	46%	29%	Well drained
42	Clallam County Area, Washington	44%	9%	Well drained
43	Thurston County Area, Washington	43%	12%	Well drained
44	Whatcom County Area, Washington	39%	19%	Well drained
45	Jefferson County Area, Washington	38%	5%	Moderately well drained
46	Skagit County Area, Washington	27%	16%	Moderately well drained
47	Kitsap County Area, Washington	10%	7%	Moderately well drained
48	Mason County, Washington	8%	4%	Moderately well drained
49	Snohomish County Area, Washington	8%	13%	Moderately well drained
50	King County Area, Washington	7%	13%	Moderately well drained
51	Pierce County Area, Washington	6%	15%	Moderately well drained
52	Island County, Washington	6%	26%	Somewhat excessively drained
53	Joint Base Lewis-McChord Area, Washington, Parts of Pierce and Thurston Counties	0%	5%	Somewhat excessively drained
54	City of Seattle, Washington	0%	1%	Moderately well drained
55	City of Tacoma, Washington	0%	1%	Moderately well drained
56	Bangor Naval Station, Washington	0%	0%	Moderately well drained