Simazine violations in Colorado
38 active public water systems in Colorado had a Simazine violation in the past three years, 4 of them in the latest quarter of EPA's data. What Simazine is and why it matters.
Systems with a Simazine violation
Latest quarter first, then largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Chemical Materials Activity West Pueblo County |
3,000 | 8 | 0 | |
|
Heartwood CO OP Housing La Plata County |
60 | 9 | 1 | |
|
Pacheco Trailer Park Rio Grande County |
36 | 13 | 3 | |
|
Deep Creek Mountain Valley Estates Mineral County |
31 | 11 | 4 | |
|
Denver Water Board Denver County |
1,287,000 | 3 | 0 | |
|
Rifle City of Garfield County |
9,489 | 2 | 0 | |
|
Palisade Town of Mesa County |
3,060 | 1 | 0 | |
|
Rangely Town of Rio Blanco County |
2,495 | 3 | 0 | |
|
Divide Water Providers INC Teller County |
570 | 1 | 0 | |
|
Granada Town of Prowers County |
515 | 12 | 1 | |
|
Saguache Town of Saguache County |
504 | 9 | 1 | |
|
Eureka WC Otero County |
498 | 9 | 1 | |
|
Mitchell Cooper Ditch Pipeline Garfield County |
415 | 4 | 0 | |
|
Encompass Preschool Parker · Douglas County |
364 | 7 | 2 | |
|
Sierra Grande School District Costilla County |
304 | 7 | 0 | |
|
Jamestown Town of Boulder County |
280 | 7 | 1 | |
|
Roaring Fork MHP Pitkin County |
200 | 10 | 0 | |
|
Altman Plants El Paso County |
188 | 8 | 1 | |
|
Castlewood Community Preschool Douglas County |
125 | 9 | 0 | |
|
Willow Brook Metro District Summit County |
120 | 9 | 0 | |
|
Kim Town of Las Animas County |
116 | 6 | 4 | |
|
Marble WC Gunnison County |
113 | 6 | 0 | |
|
United Church of Christ Parker Hilltop Parker · Douglas County |
95 | 8 | 0 | |
|
Valley Mobile Home LLC Alamosa County |
85 | 12 | 1 | |
|
Ridgewood WD Teller County |
84 | 5 | 0 | |
|
South Fork Heights Apartments Rio Grande County |
80 | 10 | 3 | |
|
Sunshine Mesa Domestic WC Delta County |
76 | 5 | 0 | |
|
Gateway School Mesa County |
75 | 1 | 0 | |
|
Timberline Lodge Grand County |
68 | 3 | 0 | |
|
Peaks Shadow LLC El Paso County |
67 | 5 | 1 | |
|
Hartman Town of Prowers County |
61 | 13 | 6 | |
|
Holbrook Center Soft WA Otero County |
54 | 6 | 1 | |
|
Western Metals Recycling Englewood · Arapahoe County |
45 | 7 | 0 | |
|
Saddlehorn Ranch MD El Paso County |
39 | 8 | 1 | |
|
Vallecito Village La Plata County |
34 | 7 | 2 | |
|
G and M Mobile Home Park Rio Grande County |
30 | 11 | 0 | |
|
Hidden Springs Ranch Routt County |
27 | 7 | 0 | |
|
Ranch at Coulter Creek HOA Garfield County |
27 | 10 | 0 |
About this data
A system is counted once if any of its violations in the past three years involved Simazine, including monitoring and reporting lapses. Rules violated and status in the table are for the whole system, not Simazine alone.
Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The Colorado records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet. Retrieved from ECHO on Oct 11, 2026.