Hydrohistorian
Cottonwood Water & Sanitation District
Boundary traced from Douglas County. About 5 km².
Where the water comes from
| Facility | Kind | Water |
|---|---|---|
| D4A WELL | Well | Groundwater |
| D11 WELL | Well | Groundwater |
| PURCHASED FROM JWPP CO0103418 | Consecutive connection (purchased) | Groundwater · from JOINT WATER PURIFICATION PLANT |
| DD1 MOVED TO JWPP CO0103418 | Well | Groundwater |
| CC4 MOVED TO JWPP CO0103418 | Well | Groundwater |
| D3 WELL | Well | Groundwater |
| DD4 WELL MOVED TO JWPP CO0103418 | Well | Groundwater |
| D2 WELL | Well | Groundwater |
| PURCHASED FROM WISE CO0103843 | Consecutive connection (purchased) | Surface water · from WISE PROJECT |
| WELL D1RR | Well | Groundwater |
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 JOINT WATER PURIFICATION PLANT, WISE PROJECT.
Sells water to 1 system: ARAPAHOE CNTY WWWA.
DWR structures that name this system
Source Probable join · fetched 2026-10-06 · matched on DWR's recorded contact or an EPA intake name; verify on the dossier
1 structure on DWR's record names this system as its contact (1). 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.
| Structure | Type | Source | District | Matched on |
|---|---|---|---|---|
| COTTONWOOD DITCH 2 0600566 | DITCH | SOUTH BOULDER CREEK | Boulder Creek | contact: COTTONWOOD 2 DITCH |
Compliance record
Source Register of another agency · fetched 2026-10-07 · 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 11 of the last 12 quarters. In violation for, in EPA's words: 2456=Total Haloacetic Acids (HAA5); 2950=TTHM; 4000=Gross Alpha, Excl. Radon and U; 4006=Combined Uranium.
No health-based or open violation on the federal record for this system.
What the regulator did about it
26 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.
| Date | Action | By |
|---|---|---|
| 2026-07-21 | St Violation/Reminder Notice | state |
| 2026-07-21 | St Public Notif requested | state |
| 2026-07-21 | St Violation/Reminder Notice | state |
| 2026-07-21 | St Public Notif requested | state |
| 2026-01-20 | St Violation/Reminder Notice | state |
| 2026-01-20 | St Public Notif requested | state |
| 2026-01-20 | St Violation/Reminder Notice | state |
| 2026-01-20 | St Public Notif requested | state |
| 2025-12-02 | St Compliance achieved RTC with 61 of 60 LCR samples collected and reported in accordance with the rule for 7/1/2025-12/31/2025 MP, no-low risk or missed samples. SOXed with date final lcr sample received by state -STF 1/23/2026 |
state |
| 2025-07-16 | St Violation/Reminder Notice | state |
| 2025-07-16 | St Public Notif requested | state |
| 2025-04-28 | St Violation/Reminder Notice | state |
| 2025-04-04 | St Compliance achieved | state |
| 2025-02-04 | St Compliance achieved RTC with samples collected on 2/4/2025 for Q1 2025 as required and reported on time. Sox date of Q1 sample collection -STF 7/16/2025 |
state |
| 2025-01-16 | St Violation/Reminder Notice | state |
| 2025-01-16 | St Public Notif requested | state |
| 2023-08-18 | St Violation/Reminder Notice | state |
| 2023-08-18 | St Public Notif requested | state |
| 2023-07-03 | St Compliance achieved | state |
| 2022-12-01 | St Compliance achieved 4Q DBPs sampled and reported on time, sox'd according to rule -SKT 4/13/2023 |
state |
20 most recent of 26; the rest are on the ECHO report.
Lead and copper
The latest 90th-percentile lead result is 0.0 mg/L (sampling period ending 2026-06-30) against an action level of 0.015 mg/L, below it. 19 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 2026-10-09 · verify at EPA UCMR occurrence data ↗
6 samples, 180 results, 2023-03-07 to 2024-01-09. 5 of the 29 PFAS were detected at least once; lithium was measured up to 29.3 µg/L (no federal limit). PFOA measured up to 0.004 µg/L, at or above EPA's 2024 limit of 0.004 µg/L.
| Contaminant | Results | Detected | Highest, µg/L | Reporting limit |
|---|---|---|---|---|
| HFPO-DA | 6 | 0 | < 0.005 | 0.005 |
| PFBA | 6 | 1 | 0.0056 | 0.005 |
| PFBS | 6 | 2 | 0.0047 | 0.003 |
| PFHxA | 6 | 3 | 0.0054 | 0.003 |
| PFHxS | 6 | 0 | < 0.003 | 0.003 |
| PFNA | 6 | 0 | < 0.004 | 0.004 |
| PFOA | 6 | 1 | 0.004 (≥ 0.004 MCL) | 0.004 |
| PFOS | 6 | 0 | < 0.004 | 0.004 |
| PFPeA | 6 | 3 | 0.0062 | 0.003 |
| lithium | 6 | 6 | 29.3 | 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 ↗.
What changed recently
Differences EPA's monthly federal record showed against the month before. A date in brackets is EPA's own; otherwise it is when this site first saw the change.
- Enforcement action: St Violation/Reminder Notice (2026-07-21)
- Enforcement action: St Public Notif requested (2026-07-21)
- Enforcement action: St Violation/Reminder Notice (2026-07-21)
- Enforcement action: St Public Notif requested (2026-07-21)
Save this system to My Water and these changes appear there each time you visit.
Common questions
Who provides drinking water in Englewood, Colorado?
Cottonwood Water & Sanitation District is the public water system serving 10,867 people in Douglas County, from purchased surface water. Its EPA public water system id is CO0118020.
Where does Cottonwood Water & Sanitation District get its water?
Cottonwood Water & Sanitation District reports purchased surface water as its primary source. EPA lists its source facilities as D4A WELL, D11 WELL, PURCHASED FROM JWPP CO0103418, DD1 MOVED TO JWPP CO0103418.
Does Cottonwood Water & Sanitation District have any drinking water violations?
EPA's compliance record shows no open health-based violations for Cottonwood Water & Sanitation District at the last monthly fetch. Older and non-health-based entries, if any, are listed on this page.
Every provider in Douglas County.
The record
EPA SDWIS federal reporting as of 2026-10-06; the compliance record above is EPA's own, fetched monthly, and the ECHO report carries the rest. Report a problem →