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California · California (CIWQS)
Costa Mesa Sanitary District
C
Often reaches water
Reported events
75
Total volume
183K gal
Reached waterways
18 (24%)
Reporting since
2007
What caused the overflows
Grease / FOG
23
Equipment Failure
21
Other / Unknown
18
Root Intrusion
13
Reported overflow events (showing 75 of 75)
| Date | Volume | Cause | Reached water | Receiving water |
|---|---|---|---|---|
| Dec 10, 2025 | 1K gal | Other / Unknown | — | — |
| Dec 10, 2025 | 900 gal | Grease / FOG | Yes | Santa Ana River (City SD, OC Channel D03, & OC Channel D04) |
| Dec 10, 2025 | 525 gal | Other / Unknown | — | — |
| Oct 27, 2025 | 3K gal | Other / Unknown | — | — |
| May 11, 2025 | 1K gal | Equipment Failure | — | Captured in catch basin |
| May 2, 2025 | 4K gal | Grease / FOG | Yes | Banning Channell |
| Jan 19, 2025 | 3K gal | Equipment Failure | — | — |
| Feb 12, 2024 | 41 gal | Other / Unknown | — | OC County Storm Drain system Channel D03 |
| Dec 27, 2023 | 75 gal | Grease / FOG | Yes | County of Orange Channel D03 & possibly Santa Ana River. |
| Dec 21, 2023 | 200 gal | Equipment Failure | Yes | OC County Open Channel D03, then to the Santa Ana river |
| Oct 11, 2023 | 310 gal | Grease / FOG | — | — |
| Oct 2, 2023 | 18K gal | Grease / FOG | — | — |
| Aug 8, 2022 | 495 gal | Grease / FOG | Yes | Surface Water |
| Dec 2, 2021 | 206 gal | Equipment Failure | — | Street/Curb and Gutter |
| Oct 2, 2020 | 4K gal | Other / Unknown | — | Separate Storm Drain |
| May 28, 2020 | 1K gal | Other / Unknown | Yes | Drainage Channel |
| Jan 18, 2020 | 220 gal | Grease / FOG | — | Street/Curb and Gutter |
| Dec 17, 2019 | 175 gal | Equipment Failure | — | Paved Surface |
| Nov 30, 2019 | 50 gal | Root Intrusion | — | Separate Storm Drain |
| Sep 17, 2019 | 2K gal | Grease / FOG | Yes | Drainage Channel |
| Sep 16, 2019 | 15 gal | Other / Unknown | — | Building or Structure;Street/Curb and Gutter |
| Sep 6, 2019 | 2K gal | Equipment Failure | Yes | Separate Storm Drain |
| Sep 5, 2019 | 80 gal | Grease / FOG | Yes | Separate Storm Drain |
| Aug 6, 2019 | 769 gal | Equipment Failure | Yes | Surface Water |
| Apr 6, 2019 | 525 gal | Grease / FOG | — | Paved Surface;Separate Storm Drain |
| Dec 13, 2018 | 3K gal | Other / Unknown | — | Paved Surface |
| Aug 13, 2018 | 26K gal | Other / Unknown | Yes | Paved Surface;Separate Storm Drain |
| Feb 5, 2018 | 380 gal | Other / Unknown | — | Unpaved surface |
| Nov 19, 2016 | 25 gal | Other / Unknown | — | Paved Surface |
| Apr 6, 2016 | 60 gal | Grease / FOG | — | Street/Curb and Gutter |
| Jan 12, 2016 | 59 gal | Root Intrusion | — | Paved Surface |
| Jan 8, 2015 | 150 gal | Root Intrusion | — | Separate Storm Drain |
| Jan 1, 2015 | 8K gal | Root Intrusion | Yes | Drainage Channel |
| Dec 5, 2014 | 17K gal | Other / Unknown | — | Other (specify below) |
| Jun 14, 2014 | 15 gal | Root Intrusion | — | Paved Surface |
| Feb 7, 2014 | 870 gal | Root Intrusion | — | Separate Storm Drain |
| Aug 31, 2013 | 79K gal | Other / Unknown | Yes | Beach |
| Mar 16, 2013 | 10 gal | Root Intrusion | — | Street/curb and gutter |
| Dec 26, 2012 | 10 gal | Grease / FOG | — | Other paved surface |
| Nov 22, 2012 | 7 gal | Root Intrusion | — | Other paved surface |
| Jul 6, 2012 | 10 gal | Root Intrusion | — | Separate storm drain |
| Feb 26, 2012 | 450 gal | Grease / FOG | Yes | Combined storm drain (combined CS only) |
| Sep 27, 2011 | 50 gal | Root Intrusion | — | Other paved surface |
| Aug 18, 2011 | 225 gal | Root Intrusion | Yes | Separate storm drain |
| Jul 7, 2011 | 45 gal | Other / Unknown | — | Street/curb and gutter |
| Jul 4, 2011 | 5 gal | Grease / FOG | — | Street/curb and gutter |
| Jan 19, 2011 | 15 gal | Equipment Failure | Yes | Surface water |
| Jan 8, 2011 | 50 gal | Equipment Failure | — | Other (specify below) |
| Jan 8, 2011 | 50 gal | Equipment Failure | — | Other (specify below) |
| Aug 29, 2010 | 100 gal | Other / Unknown | — | Unpaved surface;Other (specify below) |
| Jul 15, 2010 | 435 gal | Grease / FOG | — | Storm drain;Unpaved surface |
| Jun 27, 2010 | 40 gal | Other / Unknown | — | Unpaved surface |
| May 11, 2010 | 15 gal | Grease / FOG | — | Other (specify below) |
| Jan 29, 2009 | 50 gal | Equipment Failure | — | Other (specify below) |
| Jan 26, 2009 | 10 gal | Grease / FOG | — | Other (specify below) |
| Jan 16, 2009 | 86 gal | Other / Unknown | — | Storm drain |
| Jan 11, 2009 | 100 gal | Equipment Failure | — | Storm drain |
| Dec 30, 2008 | 10 gal | Equipment Failure | — | Other (specify below) |
| Dec 23, 2008 | 30 gal | Grease / FOG | — | Other (specify below) |
| Apr 3, 2008 | 360 gal | Other / Unknown | — | Unpaved surface |
| Mar 17, 2008 | 2K gal | Grease / FOG | Yes | Storm drain |
| Feb 26, 2008 | 450 gal | Equipment Failure | — | Other (specify below) |
| Feb 7, 2008 | 55 gal | Grease / FOG | — | Other (specify below) |
| Jan 28, 2008 | 20 gal | Root Intrusion | — | Other (specify below) |
| Jan 20, 2008 | 113 gal | Equipment Failure | — | Unpaved surface |
| Nov 18, 2007 | 45 gal | Equipment Failure | — | Other (specify below) |
| Sep 4, 2007 | 20 gal | Equipment Failure | — | Other (specify below) |
| Sep 4, 2007 | 200 gal | Equipment Failure | — | Storm drain;Street/curb and gutter |
| Jun 15, 2007 | 50 gal | Grease / FOG | — | Other (specify below) |
| May 28, 2007 | 4 gal | Grease / FOG | — | Other (specify below) |
| Apr 10, 2007 | 122 gal | Grease / FOG | — | Storm drain;Other (specify below) |
| Apr 3, 2007 | 150 gal | Root Intrusion | — | Other (specify below) |
| Mar 24, 2007 | 38 gal | Equipment Failure | Yes | Unpaved surface;Other (specify below) |
| Feb 20, 2007 | 113 gal | Equipment Failure | — | Storm drain;Other (specify below) |
| Feb 20, 2007 | 113 gal | Equipment Failure | — | Storm drain;Other (specify below) |
Source: California (CIWQS). Volumes are utility-reported estimates. Some events lack precise coordinates or volumes.