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California · California (CIWQS)
Diamond Bar City
F
Usually reaches water
Reported events
61
Total volume
227K gal
Reached waterways
41 (67%)
Reporting since
2007
What caused the overflows
Other / Unknown
25
Root Intrusion
17
Grease / FOG
10
Equipment Failure
9
Reported overflow events (showing 61 of 61)
| Date | Volume | Cause | Reached water | Receiving water |
|---|---|---|---|---|
| Jan 15, 2026 | 50 gal | Root Intrusion | Yes | Brea Creek, then to Coyote Creek, followed by San Jose Creek, all tributaries to the San Gabriel River. |
| Aug 23, 2025 | 100 gal | Grease / FOG | Yes | San Gabriel River |
| Oct 28, 2024 | 2K gal | Equipment Failure | Yes | Brea Creek - Coyote Creek / San Gabriel River |
| Jan 23, 2024 | 300 gal | Root Intrusion | Yes | San Jose Creek - Thompson Creek to U/S San Gabriel River |
| Jan 21, 2024 | 7K gal | Root Intrusion | Yes | San Jose Creek - Thompson Crk to U/S San Gabriel River |
| May 20, 2023 | 4K gal | Other / Unknown | Yes | Drainage Channel;Other (specify below);Separate Storm Drain;Street/Curb and Gutter |
| Feb 27, 2023 | 800 gal | Other / Unknown | — | Other (specify below);Unpaved surface |
| May 25, 2022 | 700 gal | Other / Unknown | Yes | Drainage Channel;Other (specify below);Separate Storm Drain |
| May 6, 2022 | 7K gal | Other / Unknown | Yes | Other (specify below);Separate Storm Drain |
| Mar 21, 2022 | 3K gal | Other / Unknown | — | Other (specify below) |
| Dec 7, 2021 | 73K gal | Equipment Failure | Yes | Drainage Channel;Other (specify below);Separate Storm Drain |
| Aug 14, 2021 | 35K gal | Other / Unknown | Yes | Drainage Channel;Other (specify below) |
| Apr 9, 2021 | 8K gal | Grease / FOG | Yes | Drainage Channel;Other (specify below);Separate Storm Drain;Street/Curb and Gutter |
| Apr 2, 2021 | 5K gal | Other / Unknown | Yes | Other (specify below);Separate Storm Drain;Street/Curb and Gutter |
| Aug 14, 2020 | 40 gal | Other / Unknown | Yes | Other (specify below);Separate Storm Drain;Street/Curb and Gutter |
| Jul 11, 2020 | 5K gal | Equipment Failure | Yes | Other (specify below) |
| Jan 6, 2020 | 17K gal | Other / Unknown | Yes | Drainage Channel;Separate Storm Drain;Street/Curb and Gutter |
| Dec 17, 2019 | 200 gal | Grease / FOG | Yes | Other (specify below);Separate Storm Drain;Street/Curb and Gutter |
| Nov 9, 2018 | 75 gal | Other / Unknown | — | Other (specify below);Paved Surface |
| Sep 22, 2017 | 3K gal | Grease / FOG | — | Other (specify below);Unpaved surface |
| Feb 1, 2017 | 200 gal | Other / Unknown | — | Other (specify below);Separate Storm Drain |
| Jan 22, 2017 | 984 gal | Other / Unknown | — | Other (specify below);Unpaved surface |
| Jan 22, 2017 | 758 gal | Other / Unknown | — | Other (specify below);Unpaved surface |
| Dec 23, 2016 | 7K gal | Other / Unknown | Yes | Drainage Channel;Other (specify below);Separate Storm Drain;Unpaved surface |
| Feb 1, 2016 | 5K gal | Other / Unknown | — | Other (specify below);Separate Storm Drain |
| Oct 8, 2015 | 600 gal | Other / Unknown | Yes | Building or Structure;Drainage Channel;Other (specify below) |
| Oct 7, 2015 | 50 gal | Other / Unknown | — | Building or Structure;Street/Curb and Gutter |
| Jul 1, 2015 | 100 gal | Other / Unknown | Yes | Drainage Channel;Separate Storm Drain;Street/Curb and Gutter;Surface Water |
| May 10, 2015 | 5K gal | Root Intrusion | Yes | Drainage Channel;Other (specify below);Separate Storm Drain;Street/Curb and Gutter |
| Apr 27, 2015 | 350 gal | Grease / FOG | — | Other (specify below);Separate Storm Drain |
| Mar 1, 2015 | 5K gal | Other / Unknown | — | Other (specify below) |
| Feb 23, 2015 | 100 gal | Other / Unknown | — | Other (specify below);Unpaved surface |
| Jan 15, 2015 | 100 gal | Root Intrusion | Yes | Other (specify below);Separate Storm Drain |
| Sep 15, 2014 | 100 gal | Grease / FOG | — | Unpaved surface |
| Mar 2, 2014 | 800 gal | Other / Unknown | — | Other (specify below) |
| Feb 28, 2014 | 1K gal | Root Intrusion | — | Building or Structure;Other (specify below) |
| Dec 16, 2013 | 800 gal | Root Intrusion | — | Other (specify below);Unpaved surface |
| Nov 4, 2013 | 5K gal | Root Intrusion | Yes | Other (specify below) |
| Jul 25, 2013 | 5K gal | Root Intrusion | Yes | Separate storm drain;Other (specify below) |
| Nov 15, 2012 | 50 gal | Grease / FOG | — | Other (specify below) |
| Nov 8, 2012 | 200 gal | Root Intrusion | Yes | Separate storm drain |
| Nov 4, 2012 | 3K gal | Root Intrusion | Yes | Combined storm drain (combined CS only) |
| Jul 22, 2012 | 7K gal | Root Intrusion | Yes | Separate storm drain;Other (specify below) |
| May 10, 2012 | 2K gal | Equipment Failure | Yes | Other (specify below) |
| Apr 15, 2011 | 300 gal | Other / Unknown | Yes | Separate storm drain;Street/curb and gutter |
| Apr 13, 2011 | 75 gal | Root Intrusion | Yes | Other (specify below) |
| Oct 2, 2010 | 500 gal | Equipment Failure | Yes | Storm drain;Other (specify below) |
| Jun 28, 2010 | 300 gal | Root Intrusion | Yes | Other (specify below) |
| Jun 6, 2010 | 200 gal | Grease / FOG | Yes | Storm drain;Other (specify below) |
| Feb 1, 2010 | 1K gal | Other / Unknown | Yes | Storm drain;Other (specify below) |
| Nov 14, 2009 | 3K gal | Equipment Failure | Yes | Storm drain;Surface water |
| Jan 29, 2009 | 200 gal | Root Intrusion | — | Other (specify below) |
| Nov 24, 2008 | 75 gal | Equipment Failure | Yes | Storm drain;Other (specify below) |
| Nov 24, 2008 | 75 gal | Equipment Failure | Yes | Storm drain;Other (specify below) |
| Oct 10, 2008 | 400 gal | Equipment Failure | — | Unpaved surface |
| Aug 5, 2008 | 2K gal | Other / Unknown | — | Other (specify below) |
| Apr 8, 2008 | 400 gal | Other / Unknown | Yes | Other (specify below) |
| Feb 20, 2008 | 300 gal | Root Intrusion | Yes | Storm drain |
| Nov 4, 2007 | 300 gal | Grease / FOG | Yes | Storm drain |
| Mar 24, 2007 | 500 gal | Grease / FOG | Yes | Separate storm drain |
| Mar 3, 2007 | 100 gal | Root Intrusion | Yes | Other (specify below) |
Source: California (CIWQS). Volumes are utility-reported estimates. Some events lack precise coordinates or volumes.