Public water system record
Doubletree Ranch Water System
Serves an area of Contra Costa County, CA · 66 people served
Federal records show 7 health-based violations and 1 monitoring/reporting issue for Doubletree Ranch Water System in the last ten years. The most serious issue in this window was a resolved Arsenic violation.
System profile
- Health-based violations, last 10 years
- 7
- Resolved
- 7
- Unresolved
- 0
- Any acute record
- No
- Monitoring issues, last 10 years
- 1
Key facts
- Doubletree Ranch Water System draws water from 2 wells.
- Highest measured level in the last 10 years: Arsenic, 38 µg/L, federal limit 10 µg/L (3.8 times the limit), 2017.
- Most recent formal enforcement: compliance order (no penalty) by California, October 2020.
- Record on file since 1980, with 25 health-based violations before October 19, 2016.
- Lead pipe inventory: 0 lead and 0 unknown out of 20 service lines.
Check whether Doubletree Ranch Water System serves your address
Health-based violations
Since October 2016Violation data reflects EPA records through March 2026. For the most current status, visit the EPA ECHO database.
| Contaminant | Rule family | Start date | Status | Acute |
|---|---|---|---|---|
|
Arsenic
Contaminant limit exceeded
Measured 33 µg/L, federal limit 10 µg/L (3.3 times the limit)
|
330 | Apr 1, 2018 | Resolved | No |
|
Arsenic
Contaminant limit exceeded
Measured 33 µg/L, federal limit 10 µg/L (3.3 times the limit)
|
330 | Jan 1, 2018 | Resolved | No |
|
Arsenic
Contaminant limit exceeded
Measured 38 µg/L, federal limit 10 µg/L (3.8 times the limit)
|
330 | Oct 1, 2017 | Resolved | No |
|
Arsenic
Contaminant limit exceeded
Measured 34 µg/L, federal limit 10 µg/L (3.4 times the limit)
|
330 | Jul 1, 2017 | Resolved | No |
|
Arsenic
Contaminant limit exceeded
|
330 | Apr 1, 2017 | Resolved | No |
|
Arsenic
Contaminant limit exceeded
Measured 28.5 µg/L, federal limit 10 µg/L (2.9 times the limit)
|
330 | Jan 1, 2017 | Resolved | No |
|
Arsenic
Contaminant limit exceeded
Measured 0.026 mg/L, federal limit 0.01 mg/L (2.6 times the limit)
|
330 | Oct 1, 2016 | Resolved | No |
Monitoring and reporting issues
Since October 2016Missed tests or reports, not contaminants found above a limit.
| Issue | Start date | Status |
|---|---|---|
|
Nitrate
Monitoring and reporting
|
Jan 1, 2019 | Resolved |
Full record since 1980
EPA's records for Doubletree Ranch Water System go back to 1980. Before October 19, 2016 they list 25 health-based violations (25 resolved) and 13 monitoring or reporting violations.
| Violations that began in | Health-based | Monitoring and reporting |
|---|---|---|
| 1980s | 0 | 11 |
| 2000s | 6 | 2 |
| 2010 to October 18, 2016 | 19 | 0 |
| October 19, 2016 to 2019 | 6 | 1 |
Most recent health-based violation before October 19, 2016: Arsenic, began October 2016, Resolved.
Show all 25 health-based violations before October 19, 2016
| Contaminant | Start date | Status |
|---|---|---|
|
Arsenic
Contaminant limit exceeded
Measured 0.026 mg/L, federal limit 0.01 mg/L (2.6 times the limit)
|
Oct 1, 2016 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.028 mg/L, federal limit 0.01 mg/L (2.8 times the limit)
|
Jul 1, 2016 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.027 mg/L, federal limit 0.01 mg/L (2.7 times the limit)
|
Mar 1, 2016 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.022 mg/L, federal limit 0.01 mg/L (2.2 times the limit)
|
Jan 1, 2016 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.023 mg/L, federal limit 0.01 mg/L (2.3 times the limit)
|
Oct 1, 2015 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.024 mg/L, federal limit 0.01 mg/L (2.4 times the limit)
|
Jul 1, 2015 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.023 mg/L, federal limit 0.01 mg/L (2.3 times the limit)
|
Apr 1, 2015 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.021 mg/L, federal limit 0.01 mg/L (2.1 times the limit)
|
Jan 1, 2015 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.02 mg/L, federal limit 0.01 mg/L (2 times the limit)
|
Oct 1, 2014 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.021 mg/L, federal limit 0.01 mg/L (2.1 times the limit)
|
Jul 1, 2014 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.022 mg/L, federal limit 0.01 mg/L (2.2 times the limit)
|
Apr 1, 2014 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.023 mg/L, federal limit 0.01 mg/L (2.3 times the limit)
|
Jan 1, 2014 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.021 mg/L, federal limit 0.01 mg/L (2.1 times the limit)
|
Oct 1, 2013 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.021 mg/L, federal limit 0.01 mg/L (2.1 times the limit)
|
Jul 1, 2013 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.022 mg/L, federal limit 0.01 mg/L (2.2 times the limit)
|
Apr 1, 2013 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.022 mg/L, federal limit 0.01 mg/L (2.2 times the limit)
|
Jan 1, 2013 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.024 mg/L, federal limit 0.01 mg/L (2.4 times the limit)
|
Oct 1, 2011 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.025 mg/L, federal limit 0.01 mg/L (2.5 times the limit)
|
Jul 1, 2011 | Resolved |
|
Total Coliform
Contaminant limit exceeded
|
Aug 1, 2010 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.024 mg/L, federal limit 0.01 mg/L (2.4 times the limit)
|
Oct 1, 2008 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.025 mg/L, federal limit 0.01 mg/L (2.5 times the limit)
|
Jul 1, 2008 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.034 mg/L, federal limit 0.01 mg/L (3.4 times the limit)
|
Oct 1, 2007 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.035 mg/L, federal limit 0.01 mg/L (3.5 times the limit)
|
Jan 1, 2007 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.025 mg/L, federal limit 0.01 mg/L (2.5 times the limit)
|
Oct 1, 2006 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.018 mg/L, federal limit 0.01 mg/L (1.8 times the limit)
|
Jul 1, 2006 | Resolved |
Enforcement actions
California regulators took 3 formal enforcement actions against Doubletree Ranch Water System between 2008 and 2020. The most recent was a compliance order (no penalty) in October 2020.
| Date | By | Action | Violations covered |
|---|---|---|---|
| Oct 12, 2020 | California | Compliance order (no penalty) | 1 violation: Nitrate |
| Oct 27, 2016 | California | Compliance order (no penalty) | 7 violations (7 health-based): Arsenic |
| Oct 21, 2008 | California | Compliance order (no penalty) | 23 violations (23 health-based): Arsenic |
What the violations mean
Arsenic
7 incidentsArsenic exceeded the federal limit
Long-term arsenic exposure is linked to cancer and cardiovascular effects
Where the water comes from
Doubletree Ranch Water System draws water from 2 wells.
Annual water quality report
Doubletree Ranch Water System must give its customers an annual water quality report (Consumer Confidence Report) by July 1, with the levels its tests found in the previous year.
Systems serving 500 or fewer people may meet the rule by telling customers the report is available on request, so you may need to ask Doubletree Ranch Water System for a copy.
Find a posted report with EPA's Consumer Confidence Report search
Testing your own water
To test the water at your tap, or a private well this record does not cover, use a laboratory certified for drinking water by California.
Certified drinking water labs by state EPA guidance for private wells