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Parker Water & Sanitation District

Parker Water & Sanitation District is the public water system serving 75,949 people in Douglas County, from surface water. It buys water from Wise Project. It also sells water wholesale to 2 systems.
Community system · EPA id CO0118040 · filed with EPA as “PARKER WSD”

Serves Sierra Ridge, Parker, Castle Pines, Lone Tree.

People served
75,949
Service connections
20,005
Primary source
Surface water
Owner
Local government
Counties served
Douglas
Water district

Boundary traced from Douglas County. About 111 km².

Where the water comes from

FacilityKindWater
REUTER HESS ARAPAHOEWellGroundwater
NEWLIN GULCH ARAPAHOEWellGroundwater
PARKER RIDGE ARAPAHOEWellGroundwater
PARKER RIDGE DAWSONWellGroundwater
RUETER HESS DENVERWellGroundwater
RUETER HESS DAWSONWellGroundwater
CC 15 ALLUVIALWellGroundwater
CC 17 ALLUVIALWellGroundwater
HESS IWellGroundwater
HESS IIWellGroundwater
NEU TOWNE ARAPAHOEWellGroundwater
REATA NORTH ARAPAHOEWellGroundwater
NEU TOWNE DAWSONWellGroundwater
REGENCY ARAPAHOEWellGroundwater
REGIONAL ARAPAHOEWellGroundwater
REGIONAL DENVERWellGroundwater
REGIONAL DAWSONWellGroundwater
REGIONAL LARAMIE FOX HILLSWellGroundwater
SALISBURY ARAPAHOEWellGroundwater
SALISBURY DAWSONWellGroundwater
CC7WellGroundwater
CC9WellGroundwater
CC13WellGroundwater
CLARKE FARMS ARAPAHOEWellGroundwater
HIDDEN RIVER ARAPAHOEWellGroundwater
CLARK FARMS A2WellGroundwater
KOA2 CCWellGroundwater
BRADBURY ARAPAHOEWellGroundwater
BRADBURY DAWSONWellGroundwater
BRADBURY LFHWellGroundwater
BRADBURY DENVERWellGroundwater
PARKER NORTH DAWSONWellGroundwater
PARKER NORTH DENVERWellGroundwater
PARKER NORTH ARAPAHOEWellGroundwater
PARKER NORTH LFHWellGroundwater
KOA 1 CCWellGroundwater
STROH RANCH ALLUVIALWellGroundwater
STROH RANCH DAWSONWellGroundwater
STROH RANCH DENVERWellGroundwater
ROBINSON RANCH ARAPAHOEWellGroundwater
STROH RANCH ARAPAHOEWellGroundwater
ROWLEY DOWNS ARAPAHOEWellGroundwater
RUSTIC DAWSONWellGroundwater
RUETER-HESS RESERVOIRIntakeSurface water
PURCHASED FROM WISE CO0103843Consecutive connection (purchased)Surface water · from WISE PROJECT
CANYONS ARAPAHOE WELLWellGroundwater
CANYONS DENVER WELLWellGroundwater
CANYONS LOWER DAWSON WELLWellGroundwater
RIDGEGATE ARAPAHOE WELLWellGroundwater
RIDGEGATE DENVER WELLWellGroundwater
RIDGEGATE LOWER DAWSON WELLWellGroundwater

These are EPA's facility records, not DWR structures. Which decreed rights sit behind an intake is the next phase; nothing here is inferred.

Wholesale connections

Buys water from WISE PROJECT.

Sells water to 2 systems: CASTLE ROCK TOWN OF, MERIDIAN MD.

DWR structures that name this system

Source Probable join · fetched 2026-09-09 · matched on DWR's recorded contact or an EPA intake name; verify on the dossier

1 structure on DWR's record 1 matches an EPA intake by name. A match says who DWR lists, not who owns the water: a ditch company can own the headgate while the system owns shares, and a consultant can be the contact. The dossier holds the decree.

StructureTypeSourceDistrictMatched on
RUETER-HESS RESERVOIR 0803347 3 CHERRY CREEK South Platte Cheesman to Denver Gage intake name: RUETER-HESS RESERVOIR

Compliance record

Source Register of another agency · fetched 2026-09-09 · verify at EPA ECHO ↗

No open violation and no health-based violation on EPA's federal record for this system at the last monthly fetch. That is a record of reported compliance, not a test result: SDWIS carries violations, not routine sample values.

EPA's own summary: violations in 5 of the last 12 quarters. In violation for, in EPA's words: 0200=Surface Water Treatment Rule; 1008=Chlorine dioxide; 1009=Chlorite; 3014=E. COLI.

No health-based or open violation on the federal record for this system.

What the regulator did about it

18 enforcement actions on this system's federal record. In Colorado the state is the primacy agency, so most actions are the state's; EPA acts directly on tribal systems and when it steps in.

DateActionBy
2025-11-26 St Compliance achieved state
2025-08-20 St Violation/Reminder Notice state
2025-08-20 St Public Notif requested state
2024-08-28 St Compliance achieved
System collected correctly in Aug 2024 lmf 11/5/2024
state
2024-08-05 St Violation/Reminder Notice state
2024-08-05 St Public Notif requested state
2024-03-26 St Violation/Reminder Notice state
2024-03-26 St Public Notif requested state
2024-03-01 St Compliance achieved state
2023-10-18 St Compliance achieved state
2023-10-17 St Violation/Reminder Notice state
2023-10-17 St Public Notif requested state
2022-12-31 St Compliance achieved state
2022-08-12 St Compliance achieved state
2022-07-27 St Violation/Reminder Notice state
2022-07-27 St Public Notif requested state
2022-02-11 St Violation/Reminder Notice state
2022-02-11 St Public Notif requested state

Lead and copper

The latest 90th-percentile lead result is 0.002 mg/L (sampling period ending 2025-12-31) against an action level of 0.015 mg/L, below it. 21 results on file.

The action level is not a health limit: it is the level at which the rule requires a system to act (corrosion control, public education, and in some cases replacing lead service lines). Lead mostly enters water from household plumbing, so a system-wide percentile does not tell you what comes out of one tap.

Violation, enforcement and lead/copper records are EPA SDWIS federal reporting, fetched monthly; the summary is EPA ECHO. Code names come from EPA's own REF_CODE_VALUE table. SDWIS carries violations, not routine sample results — nitrate, disinfection by-product and PFAS values are not in it, and a clean record here means nothing was reported as a violation, not that nothing was ever detected. For what was measured, ask the system for its Consumer Confidence Report.

PFAS and lithium: EPA's UCMR 5 monitoring, 2023–2025

Source Register of another agency · fetched 2026-09-09 · verify at EPA UCMR occurrence data ↗

29 samples, 780 results, 2024-04-01 to 2025-07-01. 5 of the 29 PFAS were detected at least once; lithium was measured up to 27.6 µg/L (no federal limit). PFOA measured up to 0.0048 µg/L, at or above EPA's 2024 limit of 0.004 µg/L.

ContaminantResultsDetectedHighest, µg/LReporting limit
HFPO-DA 26 0 < 0.005 0.005
PFBA 26 5 0.0086 0.005
PFBS 26 5 0.0046 0.003
PFHxA 26 8 0.0119 0.003
PFHxS 26 0 < 0.003 0.003
PFNA 26 0 < 0.004 0.004
PFOA 26 2 0.0048 (≥ 0.004 MCL) 0.004
PFOS 26 0 < 0.004 0.004
PFPeA 26 8 0.014 0.003
lithium 26 26 27.6 9.0

Rows shown: every detected contaminant plus the regulated PFAS and lithium; the rest were below their reporting limits. These are UCMR monitoring samples, not compliance samples. EPA's April 2024 rule set 4.0 ng/L (0.004 µg/L) for PFOA and PFOS, the same as UCMR 5's reporting limit, so any detection of either is at or above it; the rule's compliance date and its other limits have been under revision since 2025 and are not applied here. State PFAS sampling is on CDPHE's pages ↗.

Common questions

Who provides drinking water in Parker, Colorado?

Parker Water & Sanitation District is the public water system serving 75,949 people in Douglas County, from surface water. Its EPA public water system id is CO0118040.

Where does Parker Water & Sanitation District get its water?

Parker Water & Sanitation District reports surface water as its primary source. EPA lists its source facilities as REUTER HESS ARAPAHOE, NEWLIN GULCH ARAPAHOE, PARKER RIDGE ARAPAHOE, PARKER RIDGE DAWSON.

Does Parker Water & Sanitation District have any drinking water violations?

EPA's compliance record shows no open health-based violations for Parker Water & Sanitation District at the last monthly fetch. Older and non-health-based entries, if any, are listed on this page.

Places this system serves

Census places its EPA service-area boundary substantially covers. Each page lists every system serving that place.

Every provider in Douglas County.

The record

EPA SDWIS federal reporting as of 2026-09-08; the compliance record above is EPA's own, fetched monthly, and the ECHO report carries the rest. Report a problem →