How many public water systems are in Delaware?

Delaware has 494 active public water systems in EPA SDWIS records, including 220 community water systems. Together they report serving 1.1M people.

What is the largest water system in Delaware?

Artesian Water Company is the largest active public water system in Delaware, serving a reported 231,114 people.

Does Delaware rely more on groundwater or surface water?

98% of Delaware's active public water systems draw primarily on groundwater and 2% on surface water (including purchased supplies).

Delaware public water systems

494 active systems regulated under the Safe Drinking Water Act, serving a reported 1.1M people across 15 counties.

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

Active systems

494

Population served

1.1M

Community systems

220

Groundwater share

98%

System types in Delaware

220

Community water system

Non-transient non-community water system

191

Transient non-community water system

Largest water systems in Delaware

The largest active public water systems in Delaware by population served
#	Water system	County	Population served	Type	Source
1	Artesian Water Company	New Castle	231,114	Community	Purchased surface water
2	Wilmington Water Department	New Castle	107,976	Community	Surface water
3	Veolia Water Delaware, Inc.	New Castle	100,495	Community	Surface water
4	Rehoboth Pump District (Tui)	Sussex	81,417	Community	Groundwater
5	Bethany Bay Pump District	Sussex	51,000	Community	Groundwater
6	Newark Water Department	New Castle	40,000	Community	Surface water
7	Dover Water Department	Kent	39,491	Community	Groundwater
8	Dewey Beach Water Department	Sussex	31,000	Community	Purchased groundwater
9	Rehoboth Beach Water Department	Sussex	25,000	Community	Groundwater
10	Artesian Southern Sussex Regional	Sussex	18,215	Community	Groundwater
11	Middletown Water Department	New Castle	17,700	Community	Purchased surface water
12	Camden Pump District	Kent	17,208	Community	Groundwater
13	Garrison Lake Pump District	Kent	17,148	Community	Groundwater
14	Sussex Shores Water Company	Sussex	12,450	Community	Groundwater
15	Bethany Beach Water Department	Sussex	12,000	Community	Groundwater
16	Smyrna Water Department	Kent	11,813	Community	Groundwater
17	Dover Air Force Base	Kent	11,000	Community	Groundwater
18	Long Neck Water Company	Sussex	11,000	Community	Groundwater
19	Milford Water Department	Kent	9,800	Community	Groundwater
20	Church Creek (Awc)	Kent	9,654	Community	Groundwater
21	Lewes Board of Public Works	Sussex	9,627	Community	Groundwater
22	Millsboro Water Department	Sussex	8,568	Community	Groundwater
23	Bayside Pump District (Tui)	Sussex	8,400	Community	Groundwater
24	Georgetown Water Department	Sussex	7,259	Community	Groundwater
25	Artesian Northern Kent Regional	Kent	7,014	Community	Groundwater

By county

Sussex247 systems Kent136 systems New Castle76 systems Cecil11 systems Caroline5 systems Worcester4 systems Accomack4 systems Chester3 systems

Queen Anne's2 systems

Berks1 systems

Delaware1 systems

Carbon1 systems

Harford1 systems

Dorchester1 systems

Montgomery1 systems