This is a rebuild of Drinking Water Watch and not yet the official record. Use the agency’s current Drinking Water Watch for anything you need to rely on.
Lead and copper
MS0330002 , Carson Central Water Assn
Every monitoring period on record is listed here. This page applies no date range. The same list limited to the last two years.
| Analyte | Monitoring period | Samples | 90th percentile | Facility | Data quality |
|---|---|---|---|---|---|
| Copper | Jan 1, 2022 – Dec 31, 2024 | 5 | 0.318 mg/l | DS000 | Accepted |
| Lead | Jan 1, 2022 – Dec 31, 2024 | 5 | 0.0013 mg/l | DS000 | Accepted |
| Copper | Jan 1, 2019 – Dec 31, 2021 | 5 | 0.76 mg/l | DS000 | Accepted |
| Lead | Jan 1, 2019 – Dec 31, 2021 | 5 | 0.0016 mg/l | DS000 | Accepted |
| Copper | Jan 1, 2016 – Dec 31, 2018 | 5 | 0.8516 mg/l | DS000 | Accepted |
| Lead | Jan 1, 2016 – Dec 31, 2018 | 5 | 0.0018 mg/l | DS000 | Accepted |
| Copper | Jan 1, 2013 – Dec 31, 2015 | 5 | 0.5486 mg/l | DS000 | Accepted |
| Lead | Jan 1, 2013 – Dec 31, 2015 | 5 | 0.0014 mg/l | DS000 | Accepted |
| Copper | Jan 1, 2010 – Dec 31, 2012 | 5 | 0.722 mg/l | DS000 | Accepted |
| Lead | Jan 1, 2010 – Dec 31, 2012 | 5 | 0.003 mg/l | DS000 | Accepted |
| Copper | Jan 1, 2009 – Dec 31, 2009 | 6 | 0.6032 mg/l | DS000 | Accepted |
| Lead | Jan 1, 2009 – Dec 31, 2009 | 6 | 0.0008 mg/l | DS000 | Accepted |
| Copper | Jan 1, 2008 – Dec 31, 2008 | 5 | 0.531 mg/l | DS000 | Accepted |
| Lead | Jan 1, 2008 – Dec 31, 2008 | 5 | 0.0011 mg/l | DS000 | Accepted |
| Copper | Jan 1, 2007 – Dec 31, 2007 | 20 | 0.5505 mg/l | DS000 | Accepted |
| Lead | Jan 1, 2007 – Dec 31, 2007 | 20 | 0.0014 mg/l | DS000 | Accepted |
| Copper | Jul 1, 2004 – Dec 31, 2004 | 10 | 0.7388 mg/l | DS000 | Accepted |
| Lead | Jul 1, 2004 – Dec 31, 2004 | 10 | 0.0015 mg/l | DS000 | Accepted |
| Copper | Jan 1, 2004 – Jun 30, 2004 | 10 | 0.5519 mg/l | DS000 | Accepted |
| Lead | Jan 1, 2004 – Jun 30, 2004 | 10 | 0.001 mg/l | DS000 | Accepted |
| Copper | Jan 1, 2001 – Jun 30, 2001 | 5 | 0.605 mg/l | DS000 | Accepted |
| Lead | Jan 1, 2001 – Jun 30, 2001 | 5 | 0.009 mg/l | DS000 | Accepted |
| Copper | Jan 1, 1999 – Jun 30, 1999 | 5 | 0.18 mg/l | DS000 | Accepted |
| Lead | Jan 1, 1999 – Jun 30, 1999 | 5 | 0.001 mg/l | DS000 | Accepted |
| Copper | Jan 1, 1997 – Jun 30, 1997 | 10 | 0.741 mg/l | DS000 | Accepted |
| Lead | Jan 1, 1997 – Jun 30, 1997 | 10 | 0.004 mg/l | DS000 | Accepted |
| Copper | Jan 1, 1996 – Dec 31, 1996 | 10 | 2.276 mg/l | DS000 | Accepted |
| Lead | Jan 1, 1996 – Dec 31, 1996 | 10 | 0.006 mg/l | DS000 | Accepted |
| Copper | Jan 1, 1995 – Jun 30, 1995 | 10 | 0.253 mg/l | DS000 | Accepted |
| Lead | Jan 1, 1995 – Jun 30, 1995 | 10 | 0.001 mg/l | DS000 | Accepted |
| Copper | Jul 1, 1994 – Dec 31, 1994 | 10 | 1.3 mg/l | DS000 | Accepted |
| Lead | Jul 1, 1994 – Dec 31, 1994 | 10 | 0.004 mg/l | DS000 | Accepted |
| Copper | Jan 1, 1994 – Jun 30, 1994 | 11 | 7.092 mg/l | DS000 | Accepted |
| Lead | Jan 1, 1994 – Jun 30, 1994 | 11 | 0.022 mg/l | DS000 | Accepted |
| Copper | Jul 1, 1993 – Dec 31, 1993 | 11 | 8.388 mg/l | DS000 | Accepted |
| Lead | Jul 1, 1993 – Dec 31, 1993 | 11 | 0.024 mg/l | DS000 | Accepted |
No date of receipt is recorded for any of these summaries.
What the 90th percentile is
The 90th percentile of all samples collected from the distribution system is the standard that the US Environmental Protection Agency has chosen for determining compliance with the Lead and Copper Action Level under the federal Lead and Copper Rule. The 90th percentile is determined by ranking all sample results from lowest to highest and finding a result that is 90% of the number of sample results from the top. For example, if there are 10 sample results, the 90th percentile would be the 9th sample result from the top.
From the help text published with these pages.