Skip to content
AquaCensus

Island County, Washington — public water systems

At a glance

307 active public water systems are filed under Island County, Washington in EPA's SDWIS records, together reporting 102,977 people served. The largest is City of Oak Harbor, which reports serving 23,675 people. 233 are community water systems serving people where they live; the other 74 are non-community systems, such as schools, workplaces, campgrounds and gas stations with their own supply.

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

Active systems

307

Population served

103K

Community systems

233

Groundwater share

99%

How does Island County compare with other Washington counties?

Island County has the 3rd-most active public water systems among the 72 counties listed for active Washington systems in EPA records; among the 44 with 3 or more systems, the median has 75. Its systems report 102,977 people served in total, the 16th-largest county figure in the state and 1% of the statewide total. The average system here reports serving 335 people, well below the Washington average of 2,172. Population figures are what each system reports; people served by more than one system, such as a wholesaler and the town that buys from it, are counted by each.

Where does Island County's drinking water come from?

By primary water source, Island County's active systems draw on groundwater (302, 98%), purchased surface water (3, 1%) and purchased groundwater (2, 0.7%). Overall, 99% rely mainly on groundwater (including purchased groundwater) and 1% on surface water, compared with 94% and 5.7% across Washington. Groundwater means the system draws its water from wells or springs fed by underground aquifers. The county's largest system, City of Oak Harbor, draws primarily on purchased surface water.

What kinds of water systems operate in Island County?

Island County's active systems break down as 233 community systems (76%), 13 non-transient non-community systems (4.2%) and 61 transient non-community systems (20%). A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. A non-transient non-community water system regularly serves at least 25 of the same people for more than six months a year, but not where they live. Schools, factories, office buildings and hospitals with their own supply are typical examples. A transient non-community water system serves places where people do not stay long, such as gas stations and campgrounds, and regularly serves at least 25 people a day for at least 60 days a year. EPA lists their owner types as private (89%), local government (8.8%), state government (1.6%) and federal government (0.3%).

The 50 largest water systems in Island County

🔒 Create a free account to export CSV
Active public water systems in Island County, Washington
#Water systemCountyPopulation servedTypeSource
1Oak Harbor City ofIsland23,675CommunityPurchased surface water
2Naval Air Station/Whidbey IslandIsland16,595CommunityPurchased surface water
3Coupeville Town ofIsland4,142CommunityGroundwater
4Camano Water AssociationIsland2,592CommunityGroundwater
5Clinton Water DistrictIsland1,980CommunityGroundwater
6Camano Island State ParkIsland1,718Transient non-communityGroundwater
7Maxwelton Water SystemIsland1,700Non-transient non-communityGroundwater
8Fort Ebey State ParkIsland1,443Transient non-communityGroundwater
9Langley City ofIsland1,416CommunityGroundwater
10Harbor Hills Community Water SystemIsland1,373CommunityGroundwater
11Freeland Water and Sewer DistrictIsland1,264CommunityGroundwater
12South Whidbey State ParkIsland1,203Transient non-communityGroundwater
13W&B Waterworks 1Island1,112CommunityGroundwater
14Camano Co-Op Water & Power CoIsland1,071CommunityGroundwater
15Bayview Beach Water DistrictIsland1,035CommunityGroundwater
16Scatchet Head Water DistrictIsland900CommunityGroundwater
17Rolling Hills-GlencairnIsland872CommunityGroundwater
18Admirals Cove Water DistrictIsland870CommunityGroundwater
19Camaloch AssociationIsland825CommunityGroundwater
20Hillcrest Village Water Co Inc.Island770CommunityGroundwater
21Northgate Terrace Community ClubIsland750CommunityGroundwater
22Lost Lake Property Owners AssnIsland736CommunityGroundwater
23Vistaire Water SystemIsland647CommunityGroundwater
24Mecca Community AssociationIsland619CommunityGroundwater
25Camano Vista Water DistrictIsland591CommunityGroundwater
26North Whidbey Water DistrictIsland568CommunityPurchased surface water
27Sandy Hook Yacht Club EstatesIsland540CommunityGroundwater
28Madrona Beach Comm Water SystemIsland539CommunityGroundwater
29Sunvista Sunlight Beach HoaIsland500CommunityGroundwater
30Sea View Water LLCIsland496CommunityGroundwater
31Lagoon Point Water DistrictIsland495CommunityGroundwater
32Saratoga Water DistrictIsland477CommunityGroundwater
33Penn Cove Water and Sewer DistrictIsland460CommunityGroundwater
34Dugualla Community Inc.Island459CommunityGroundwater
35Combined Water SystemIsland435CommunityGroundwater
36Saratoga Beach Owners AssnIsland425CommunityGroundwater
37Silver Lake WaterIsland425CommunityGroundwater
38Crosswoods Water SystemIsland420CommunityGroundwater
39Whidbey West Water Assoc.Island415CommunityGroundwater
40Sierra Country ClubIsland400CommunityGroundwater
41Crockett Lake Water DistrictIsland325CommunityGroundwater
42Rocky Point Community ClubIsland320CommunityGroundwater
43Swantown Water DistrictIsland318CommunityGroundwater
44Camano Laguna Vista Water AssocIsland310CommunityGroundwater
45Beachcomber H2o CoIsland310CommunityGroundwater
46Cama Beach State ParkIsland306Transient non-communityGroundwater
47Parkwood Manor MHPIsland301CommunityGroundwater
48Kens KornerIsland300Non-transient non-communityGroundwater
49Mariners Cove Beach Club Inc.Island300CommunityGroundwater
50Driftwood Heights AssociationIsland298CommunityGroundwater

All other water systems in Island County (257)

The remaining active systems filed under Island County, largest first, with the population each reports serving.

Island County water systems: frequently asked questions

How many public water systems are in Island County, Washington?

EPA's SDWIS records file 307 active public water systems under Island County, Washington: 233 community systems (76%), 13 non-transient non-community systems (4.2%) and 61 transient non-community systems (20%).

Who supplies drinking water in Island County, WA?

The largest community water systems filed under Island County are City of Oak Harbor (23,675 people served), Naval Air Station/Whidbey Island (16,595 people served) and Town of Coupeville (4,142 people served). Which system serves a particular address depends on its service area, which EPA's SDWIS records do not include; a water bill or the local utility can confirm it.

Does Island County's drinking water come from groundwater or surface water?

Of the 307 active public water systems in Island County, 99% draw mainly on groundwater and 1% on surface water, counting purchased supplies. The largest system, City of Oak Harbor, uses purchased surface water.

Where can I find a water quality report for Island County?

Each community water system must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1, covering the previous calendar year. 233 community systems are filed under Island County, so the report to look for is the one from the system that supplies your address.

How can I check violations for a water system in Island County?

Open the system's profile from the list on this page. Each profile shows the most recent Safe Drinking Water Act violations in EPA's records, with plain-English labels and whether each one is resolved. For current compliance status, EPA ECHO is the primary source.

More Washington water systems

About this data

Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.

Cite as: AquaCensus, “Public water systems in Island County, Washington”, https://aquacensus.com/water-systems/washington/island (data as of October 1, 2026).