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California · California (CIWQS)

Simi Valley City

D
Frequently reaches water
Reported events
49
Total volume
153K gal
Reached waterways
16 (33%)
Reporting since
2007

What caused the overflows

Equipment Failure
19
Other / Unknown
15
Grease / FOG
10
Root Intrusion
5

Reported overflow events (showing 49 of 49)

DateVolumeCauseReached waterReceiving water
Oct 5, 20255K galEquipment Failure——
Jun 2, 2025158 galEquipment Failure——
May 3, 20256K galEquipment Failure——
Oct 19, 2024131 galGrease / FOG——
Jul 16, 20248K galEquipment FailureYesArroyo Simi Flood Control Channel
Feb 11, 2024650 galEquipment Failure——
Jul 5, 2023270 galGrease / FOG——
Mar 13, 2023450 galEquipment Failure—Unpaved surface
Feb 26, 2022120 galOther / Unknown—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Nov 28, 202134K galGrease / FOGYesSeparate Storm Drain
Nov 1, 2021513 galRoot Intrusion—Other (specify below)
Oct 18, 202150 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Apr 19, 20211K galEquipment Failure—Paved Surface;Street/Curb and Gutter;Unpaved surface
Dec 17, 20201K galOther / UnknownYesOther (specify below)
Dec 17, 20201K galEquipment Failure—Other (specify below)
Oct 19, 20192K galEquipment FailureYesPaved Surface;Separate Storm Drain;Street/Curb and Gutter
Dec 30, 20181K galEquipment Failure—Paved Surface
Apr 18, 2018150 galOther / Unknown—Street/Curb and Gutter
Feb 26, 2018250 galRoot Intrusion—Unpaved surface
Jun 2, 2017300 galGrease / FOGYesSeparate Storm Drain
Apr 27, 201550 galGrease / FOG—Separate Storm Drain;Street/Curb and Gutter
Nov 15, 2014100 galRoot Intrusion—Street/Curb and Gutter
Nov 8, 2014500 galGrease / FOG—Unpaved surface
Sep 4, 20141K galRoot Intrusion—Other (specify below)
Aug 27, 2014700 galEquipment Failure—Other (specify below)
May 9, 20132K galRoot IntrusionYesSeparate storm drain;Street/curb and gutter;Surface water
Jan 30, 2013125 galOther / Unknown—Other (specify below)
Aug 5, 2012180 galGrease / FOG—Combined storm drain (combined CS only);Separate storm drain;Street/curb and gutter
Jul 21, 2012200 galOther / Unknown—Separate storm drain;Street/curb and gutter
Dec 26, 2011450 galEquipment FailureYesOther paved surface;Separate storm drain;Surface water
Dec 8, 201110K galOther / UnknownYesSeparate storm drain;Street/curb and gutter
Jun 9, 2011300 galOther / UnknownYesOther (specify below)
Dec 21, 2010200 galOther / Unknown—Street/curb and gutter
Oct 31, 20105K galEquipment Failure—Other (specify below)
Aug 30, 20094K galOther / UnknownYesStorm drain;Street/curb and gutter;Surface water
Jan 10, 2009250 galOther / UnknownYesStorm drain;Street/curb and gutter;Surface water
Oct 30, 2008250 galEquipment Failure—Other paved surface;Street/curb and gutter
Oct 10, 200850 galEquipment Failure—Other paved surface
Jul 10, 2008500 galEquipment FailureYesSurface water
Mar 21, 2008200 galEquipment Failure—Storm drain
Feb 22, 200820K galOther / Unknown—Other (specify below)
Jan 20, 200850 galGrease / FOG—Other paved surface
Aug 20, 20076K galOther / UnknownYesSurface water
Aug 4, 20078K galOther / UnknownYesUnpaved surface
May 22, 200716K galEquipment FailureYesSurface water
May 22, 200716K galOther / UnknownYesSurface water
Apr 12, 2007200 galOther / Unknown—Building or structure;Other paved surface
Apr 5, 2007102 galGrease / FOG—Other (specify below)
Apr 5, 2007102 galGrease / FOG—Unpaved surface

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