New Castle County, DE Water Quality Guide

County-level water-system mapping, municipality links, CCR availability, and private-well context for New Castle County.

About New Castle County, DE Water

New Castle County is not one water system. Municipal systems, investor-owned utilities, subdivisions, noncommunity systems, and private wells may all occur in the county.

Local Delaware water context for New Castle County

New Castle has dense interconnected public-water service around Wilmington and Newark, including Artesian, Veolia, Wilmington, and Newark systems, plus private wells in less-served areas. DNREC has monitored saltwater conditions in the Potomac aquifer near the Delaware River, and older housing can make household plumbing relevant to lead results.

Confirm the exact PWSID and current CCR for public water. For private wells or a property near a documented investigation area, use DNREC well records and a certified laboratory rather than applying a countywide assumption.

QuestionUseful local starting point
Public waterConfirm the exact PWS ID in Delaware Drinking Water Watch or on the current bill.
Service territoryReview the official Delaware PSC CPCN water-territory GIS layer as a utility-territory discovery tool; it is not an address-level guarantee.
Private wellReview the DNREC well permit/record and water-use/water-level data, then use a certified laboratory or Delaware DPH testing resources.
UD/DGS research contextFor aquifer, groundwater, and regional research context, review DGS/UD hydrologic information and DGS digital datasets. These sources are not address-level tap-water results.
Data-source guideUse the Delaware water data-source guide to interpret PWS, CCR, well, territory, and lab records.
Before treatmentMatch the system to the actual CCR or test result; a municipality is not one water system.

Water system providers for New Castle County, DE

Provider rows are based on EPA service-area relationships and may include modeled boundaries. Confirm the exact system through Delaware Drinking Water Watch or your current bill.

PWS IDSystemProviderContactMapping statusOfficial links
DE0000013FORT DUPONTFORT DUPONTSee utility / DWW recordWater Utility; Area type: Institution; Mapped overlap: 0.121645Provider website
Drinking Water Watch
DE0000552ARTESIAN WATER COMPANYArtesian Water Company1-800-332-5114Water Utility; Area type: Residential Area; Mapped overlap: 0.00192Provider website
Drinking Water Watch
DE0000564VEOLIA WATER DELAWARE, INCVeolia Water Delaware (formerly SUEZ)1-302-633-5900EPA service-area relationship; Area type: Residential Area; Mapped overlap: 0.33809Provider website
Drinking Water Watch
DE0000566DELAWARE CITY WATER DEPARTMENT (AWC)DELAWARE CITY WATER DEPARTMENT (AWC)See utility / DWW recordWater Utility; Area type: Municipality; Mapped overlap: 0.318301Provider website
Drinking Water Watch
DE0000614MIDDLETOWN WATER DEPARTMENTMIDDLETOWN WATER DEPARTMENTSee utility / DWW recordFederal agency; Area type: Municipality; Model: Random Forest; Mapped overlap: 0.129603Provider website
Drinking Water Watch
DE0000630NEWARK WATER DEPARTMENTNEWARK WATER DEPARTMENTSee utility / DWW recordLocal; Area type: Municipality; Mapped overlap: 0.9408Provider website
Drinking Water Watch
DE0000634MUNICIPAL SERVICES COMMISSIONMUNICIPAL SERVICES COMMISSIONSee utility / DWW recordFederal agency; Area type: Municipality; Model: Random Forest; Mapped overlap: 0.939452Provider website
Drinking Water Watch
DE0000663WILMINGTON WATER DEPARTMENTWILMINGTON WATER DEPARTMENTSee utility / DWW recordEPA service-area relationship; Area type: Municipality; Mapped overlap: 0.42521Provider website
Drinking Water Watch
DE0020122WILLOW GROVE MILLWILLOW GROVE MILLSee utility / DWW recordFederal agency; Area type: Residential Area; Model: Random Forest; Mapped overlap: 0.20877Provider website
Drinking Water Watch

System details and report coverage

System / PWS IDSystem typeSample year(s)Report year(s)Coverage statusOfficial record
DE0000013
FORT DUPONT
community-water-system2025/20262025/2026PWS record mapped; local contaminant row not parsedOfficial record/report source
DE0000552
ARTESIAN WATER COMPANY
community-water-system2025, 2024, 20232025, 2024, 2023Extracted contaminant rows availableOfficial record/report source
DE0000564
VEOLIA WATER DELAWARE, INC
community-water-system2024, 20212024Extracted contaminant rows availableOfficial record/report source
DE0000566
DELAWARE CITY WATER DEPARTMENT (AWC)
community-water-system2025/20262025/2026Current report source indexedOfficial record/report source
DE0000614
MIDDLETOWN WATER DEPARTMENT
community-water-system2025/20262025/2026PWS record mapped; local contaminant row not parsedOfficial record/report source
DE0000630
NEWARK WATER DEPARTMENT
community-water-system2025, 2024-20252026Extracted contaminant rows availableOfficial record/report source
DE0000634
MUNICIPAL SERVICES COMMISSION
community-water-system2024, 20232024Extracted contaminant rows availableOfficial record/report source
DE0000663
WILMINGTON WATER DEPARTMENT
community-water-system20242025Extracted contaminant rows availableOfficial record/report source
DE0020122
WILLOW GROVE MILL
community-water-system2024, 20232024Extracted contaminant rows availableOfficial record/report source

Reported contaminant data and report status for New Castle County, DE

PWS IDSystemData pointReported level/statusLimit or contextComparisonSample yearReport yearSource PDF pageSource
DE0000013FORT DUPONTLocal report statusDWW system record mapped; CCR row not locally parsedSee current reportNot a contaminant result2025/20262025/2026Source
DE0000552ARTESIAN WATER COMPANYNitrate6.87 ppm10Below20242024Source
DE0000552ARTESIAN WATER COMPANYChlorine (free and total)3.30 ppm4 MRDLBelow20252025Source
DE0000552ARTESIAN WATER COMPANYHaloacetic acids, total15.69 ppb60Below20252025Source
DE0000552ARTESIAN WATER COMPANYLead, 90th percentile1 ppb15 action levelBelow20232023Source
DE0000552ARTESIAN WATER COMPANYTotal hardness113 ppmSecondary; no MCLReported20232023Source
DE0000552ARTESIAN WATER COMPANYChloride59 ppm250 secondaryBelow20232023Source
DE0000552ARTESIAN WATER COMPANYIron0.254 MG/LSecondary standard; see Delaware DPH tableReported2024202411Source
DE0000552ARTESIAN WATER COMPANYSodium48.6 MG/LSecondary standard; see Delaware DPH tableReported2024202411Source
DE0000552ARTESIAN WATER COMPANYManganese0.017 MG/LSecondary standard; see Delaware DPH tableReported2023202411Source
DE0000552ARTESIAN WATER COMPANYMethyl Tert-Butyl Ether0.8 UG/LSecondary standard; see Delaware DPH tableReported2023202417Source
DE0000552ARTESIAN WATER COMPANYNickel0.007 MG/LSecondary standard; see Delaware DPH tableReported2023202424Source
DE0000564VEOLIA WATER DELAWARE, INCAlkalinity, Total48.64 MG/LSecondary standard; see Delaware DPH tableReported20242024373Source
DE0000564VEOLIA WATER DELAWARE, INCChloride65.0295 MG/LSecondary standard; see Delaware DPH tableReported20242024373Source
DE0000564VEOLIA WATER DELAWARE, INCIron0 MG/LSecondary standard; see Delaware DPH tableReported20242024373Source
DE0000564VEOLIA WATER DELAWARE, INCSodium29.3486 MG/LSecondary standard; see Delaware DPH tableReported20242024373Source
DE0000564VEOLIA WATER DELAWARE, INCSulfate23.7965 MG/LSecondary standard; see Delaware DPH tableReported20242024373Source
DE0000564VEOLIA WATER DELAWARE, INCManganese0.037 MG/LSecondary standard; see Delaware DPH tableReported20212024375Source
DE0000564VEOLIA WATER DELAWARE, INCMethyl Tert-Butyl Ether0 UG/LSecondary standard; see Delaware DPH tableReported20242024375Source
DE0000566DELAWARE CITY WATER DEPARTMENT (AWC)Local report statusCurrent CCR/report source indexedSee current reportNot a contaminant result2025/20262025/2026Source
DE0000614MIDDLETOWN WATER DEPARTMENTLocal report statusDWW system record mapped; CCR row not locally parsedSee current reportNot a contaminant result2025/20262025/2026Source
DE0000630NEWARK WATER DEPARTMENTNitrate5 ppm10Below202520266Source
DE0000630NEWARK WATER DEPARTMENTTotal trihalomethanes92.7 ppb highest level; RAA 30.88–60.2080Reported; see RAA footnote202520267Source
DE0000630NEWARK WATER DEPARTMENTPFOS1.72 ppt averageNo Delaware CCR MCL shown in tableOccurrence/reporting result2024-202520268Source
DE0000630NEWARK WATER DEPARTMENTPFOA4.355 ppt averageNo Delaware CCR MCL shown in tableOccurrence/reporting result2024-202520268Source
DE0000634MUNICIPAL SERVICES COMMISSIONChloride107.4428 MG/LSecondary standard; see Delaware DPH tableReported20242024261Source
DE0000634MUNICIPAL SERVICES COMMISSIONSulfate13.1807 MG/LSecondary standard; see Delaware DPH tableReported20242024261Source
DE0000634MUNICIPAL SERVICES COMMISSIONMethyl Tert-Butyl Ether0 UG/LSecondary standard; see Delaware DPH tableReported20232024273Source
DE0000663WILMINGTON WATER DEPARTMENTNitrate5.8 ppm highest level, Porter Filter Plant10Below202420252Source
DE0000663WILMINGTON WATER DEPARTMENTTotal trihalomethanes8 ppb highest level80Below202420254Source
DE0000663WILMINGTON WATER DEPARTMENTChlorine2.05 ppm highest level4 MRDLBelow202420253Source
DE0020122WILLOW GROVE MILLChloride5.9619 MG/LSecondary standard; see Delaware DPH tableReported20242024385Source
DE0020122WILLOW GROVE MILLSulfate6.5734 MG/LSecondary standard; see Delaware DPH tableReported20242024385Source
DE0020122WILLOW GROVE MILLMethyl Tert-Butyl Ether0 UG/LSecondary standard; see Delaware DPH tableReported20232024385Source

Municipality pages

Official records

How to Read This Info for New Castle County, DE

Use the municipality and PWS ID to identify the applicable system. Do not apply one system’s report to the entire county. Rows labeled “Local report status” are report-coverage indicators, not contaminant measurements.

Frequently asked questions

How do I identify my provider?

Start with your bill, then verify the PWS ID in Delaware Drinking Water Watch. Use the municipality links above as a discovery tool, not an address-level guarantee.

Are countywide contaminant levels available?

Rows are shown by PWS ID, not as a single countywide result. Current CCR rows are included where parsed; other systems show a transparent report-status row and official lookup link.

Provider mapping may be modeled, dated, incomplete, or limited. Verify current service and reports through Delaware official sources.

Last reviewed: July 21, 2026

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