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California · California (CIWQS)

Union Sanitary District

B
Seldom reaches water
Reported events
84
Total volume
73K gal
Reached waterways
12 (14%)
Reporting since
2007

What caused the overflows

Root Intrusion
25
Grease / FOG
23
Other / Unknown
21
Equipment Failure
15

Reported overflow events (showing 84 of 84)

DateVolumeCauseReached waterReceiving water
Apr 18, 202688 galEquipment Failure——
Aug 25, 2025188 galEquipment Failure——
Jan 10, 20253K galEquipment Failure——
Oct 16, 20249K galGrease / FOG——
Oct 16, 20245K galGrease / FOG——
Aug 29, 2024138 galOther / Unknown——
Sep 6, 2023164 galOther / Unknown——
May 16, 2023804 galOther / Unknown—Unpaved surface
Mar 16, 202217 galEquipment Failure—Paved Surface;Street/Curb and Gutter
May 12, 202187 galOther / Unknown—Unpaved surface
Apr 24, 2021891 galGrease / FOG—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Jul 29, 202016 galOther / Unknown—Paved Surface;Street/Curb and Gutter
Oct 16, 20194 galRoot Intrusion—Paved Surface;Street/Curb and Gutter;Unpaved surface
Mar 8, 20192K galGrease / FOG—Separate Storm Drain;Street/Curb and Gutter
Nov 8, 201867 galOther / Unknown—Paved Surface;Street/Curb and Gutter
Jan 4, 20185 galRoot Intrusion—Unpaved surface
Oct 4, 2017501 galOther / Unknown—Unpaved surface
Feb 14, 201796 galEquipment Failure—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Nov 18, 2016140 galGrease / FOGYesDrainage Channel
Oct 18, 20164 galRoot Intrusion—Street/Curb and Gutter
Oct 13, 2016620 galRoot Intrusion—Separate Storm Drain
Jun 18, 2016360 galGrease / FOG—Separate Storm Drain
Apr 6, 2016900 galGrease / FOG—Separate Storm Drain
Jan 20, 2016350 galRoot Intrusion—Street/Curb and Gutter
Sep 4, 201553 galOther / Unknown—Unpaved surface
Jul 27, 201542 galEquipment Failure—Separate Storm Drain
Apr 28, 20155K galEquipment Failure—Drainage Channel;Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Apr 14, 20154K galRoot IntrusionYesDrainage Channel;Separate Storm Drain;Surface Water
Oct 28, 2014495 galRoot IntrusionYesPaved Surface;Separate Storm Drain;Surface Water;Unpaved surface
Oct 1, 201452 galEquipment Failure—Separate Storm Drain
Sep 2, 2014325 galRoot Intrusion—Separate Storm Drain
Sep 1, 2014746 galEquipment Failure—Separate Storm Drain
Jun 1, 2014939 galEquipment Failure—Separate Storm Drain
Mar 9, 201410 galOther / Unknown—Paved Surface;Street/Curb and Gutter
Nov 29, 2013618 galGrease / FOG—Separate Storm Drain;Street/Curb and Gutter
Nov 8, 20131 galGrease / FOG—Paved Surface
Jul 15, 20132K galRoot IntrusionYesOther paved surface;Separate storm drain;Street/curb and gutter;Unpaved surface;Other (specify below)
May 28, 201210 galRoot Intrusion—Separate storm drain;Street/curb and gutter
May 23, 201219 galOther / Unknown—Separate storm drain;Street/curb and gutter
Apr 14, 20123 galGrease / FOG—Other paved surface
Mar 29, 201227 galGrease / FOG—Separate storm drain
Jan 31, 2012110 galGrease / FOG—Unpaved surface
Dec 19, 201125 galOther / Unknown—Building or structure;Unpaved surface
Aug 1, 2011720 galGrease / FOG—Separate storm drain;Street/curb and gutter
Jul 30, 20111K galGrease / FOG—Separate storm drain;Street/curb and gutter
Jun 26, 2011108 galOther / Unknown—Separate storm drain
Jun 7, 201127 galEquipment Failure—Other (specify below)
Dec 24, 201040 galOther / Unknown—Street/curb and gutter
Dec 9, 2010250 galEquipment Failure—Separate storm drain
Nov 21, 201010 galGrease / FOG—Other paved surface;Unpaved surface
Aug 10, 2010212 galRoot Intrusion—Storm drain;Street/curb and gutter
Jul 21, 2010150 galOther / Unknown—Storm drain;Street/curb and gutter;Unpaved surface
Jun 1, 20103 galRoot Intrusion—Building or structure
May 3, 2010100 galRoot Intrusion—Other paved surface;Storm drain
Apr 4, 2010600 galRoot Intrusion—Storm drain;Street/curb and gutter
Mar 31, 20104 galOther / Unknown—Building or structure
Feb 7, 2010320 galRoot IntrusionYesOther paved surface;Separate storm drain;Street/curb and gutter;Unpaved surface
Feb 2, 2010200 galGrease / FOG—Street/curb and gutter;Unpaved surface
Jan 2, 2010200 galGrease / FOG—Other paved surface;Street/curb and gutter
Dec 10, 200950 galRoot Intrusion—Street/curb and gutter
Nov 16, 2009780 galRoot Intrusion—Storm drain;Street/curb and gutter
Oct 14, 200912K galEquipment FailureYesOther (specify below)
Mar 16, 200920 galOther / Unknown—Street/curb and gutter;Unpaved surface
Feb 10, 200915 galRoot Intrusion—Street/curb and gutter;Unpaved surface
Jan 22, 2009234 galRoot Intrusion—Other paved surface;Storm drain;Street/curb and gutter
Dec 25, 20083K galGrease / FOGYesStorm drain;Street/curb and gutter;Surface water;Unpaved surface
Oct 25, 2008600 galGrease / FOG—Storm drain;Street/curb and gutter
Oct 1, 200832 galEquipment Failure—Storm drain
Sep 16, 2008100 galOther / Unknown—Unpaved surface
Aug 1, 20082K galRoot Intrusion—Unpaved surface
Jul 22, 2008250 galOther / Unknown—Other paved surface;Unpaved surface
Jun 9, 2008170 galOther / Unknown—Other paved surface;Storm drain;Street/curb and gutter
Jun 9, 20085K galGrease / FOG—Other paved surface;Storm drain;Unpaved surface
Jun 3, 2008250 galRoot Intrusion—Storm drain;Street/curb and gutter
May 22, 2008340 galRoot IntrusionYesSeparate storm drain;Surface water
Apr 12, 20085 galRoot Intrusion—Street/curb and gutter
Jan 30, 20082K galRoot IntrusionYesStorm drain;Street/curb and gutter;Surface water
Dec 20, 2007880 galOther / UnknownYesSurface water
Oct 30, 200750 galGrease / FOG—Street/curb and gutter;Unpaved surface
Oct 2, 2007350 galEquipment Failure—Other (specify below)
Sep 23, 2007675 galGrease / FOGYesSeparate storm drain;Other (specify below)
Aug 20, 2007350 galRoot IntrusionYesOther paved surface;Storm drain;Surface water
Jul 13, 2007650 galOther / Unknown—Other paved surface;Storm drain
May 18, 20075 galGrease / FOG—Unpaved surface

Source: California (CIWQS). Volumes are utility-reported estimates. Some events lack precise coordinates or volumes.