Mason County, Washington — public water systems

240 active public water systems serve Mason County, reporting 75.6K people served.

Dataset updated July 2026 . Source: EPA SDWIS/ECHO, refreshed quarterly.

Active systems

240

Population served

75.6K

Community systems

120

Groundwater share

100%

Water systems in Mason County

Active public water systems in Mason County, Washington
#	Water system	County	Population served	Type	Source
1	Shelton City of	Mason	15,089	Community	Groundwater
2	Belfair Water District 1	Mason	4,432	Community	Groundwater
3	Lake Cushman System 5	Mason	3,675	Community	Groundwater
4	Twanoh State Park	Mason	3,173	Transient non-community	Groundwater
5	Belfair State Park	Mason	2,411	Transient non-community	Groundwater
6	Timberlake Community Club Inc.	Mason	2,337	Community	Groundwater
7	Washington Corrections Center	Mason	2,223	Community	Groundwater
8	Alderbrook Water Co	Mason	2,154	Community	Groundwater
9	Lake Limerick Water	Mason	2,148	Community	Groundwater
10	Lakeland Village Water	Mason	2,120	Community	Groundwater
11	Hoodsport	Mason	1,853	Community	Groundwater
12	Shorecrest Estates Water Co	Mason	1,321	Community	Groundwater
13	North Mason High School	Mason	1,300	Non-transient non-community	Groundwater
14	Beards Cove	Mason	1,100	Community	Groundwater
15	Potlatch State Park	Mason	1,055	Transient non-community	Groundwater
16	Fawn Lake Maintenance Comm	Mason	1,044	Community	Groundwater
17	Lake Cushman System 3	Mason	917	Community	Groundwater
18	Pioneer School District	Mason	903	Non-transient non-community	Groundwater
19	Lynch Cove	Mason	721	Community	Groundwater
20	Jarrell Cove State Park	Mason	715	Transient non-community	Groundwater
21	Union	Mason	700	Community	Groundwater
22	Oak Park	Mason	695	Community	Groundwater
23	Sand Hill Elementary	Mason	650	Non-transient non-community	Groundwater
24	Twanoh Falls Beach Club	Mason	481	Community	Groundwater
25	Schafer State Park	Mason	465	Transient non-community	Groundwater
26	Hartstene Pointe	Mason	460	Community	Groundwater
27	Allyn Shopping Center	Mason	414	Community	Groundwater
28	Ridge Motorsports Park	Mason	403	Transient non-community	Groundwater
29	Paradise Estates	Mason	403	Community	Groundwater
30	Port of Allyn	Mason	397	Community	Groundwater
31	Hood Canal	Mason	368	Community	Groundwater
32	Tahuya River Valley Water District	Mason	367	Community	Groundwater
33	Hiapark	Mason	360	Community	Groundwater
34	Lake Arrowhead	Mason	343	Community	Groundwater
35	Emerald Lake	Mason	331	Community	Groundwater
36	Port of Shelton Johns Prairie	Mason	328	Non-transient non-community	Purchased groundwater
37	Rustlewood	Mason	322	Community	Groundwater
38	Collins Lake Community Club	Mason	322	Community	Groundwater
39	Treasure Island Country Club	Mason	321	Community	Groundwater
40	Taylor Station	Mason	314	Transient non-community	Groundwater
41	Colony Surf Water Supply	Mason	297	Community	Groundwater
42	Maggie Lake Water District	Mason	287	Community	Groundwater
43	Port of Shelton Sanderson Field	Mason	283	Non-transient non-community	Groundwater
44	View Ridge Heights	Mason	271	Community	Groundwater
45	Mary M Knight School	Mason	270	Non-transient non-community	Groundwater
46	Southside Elementary School	Mason	260	Non-transient non-community	Groundwater
47	Grapeview School	Mason	257	Non-transient non-community	Groundwater
48	Union Food Mart	Mason	255	Transient non-community	Groundwater
49	Island Lake Manor	Mason	233	Community	Groundwater
50	Sunset Beach	Mason	224	Community	Groundwater