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California · California (CIWQS)

Castro Valley Sanitary District

D
Frequently reaches water
Reported events
94
Total volume
322K gal
Reached waterways
31 (33%)
Reporting since
2007

What caused the overflows

Root Intrusion
30
Grease / FOG
20
Rainfall / Flooding
17
Other / Unknown
13
Equipment Failure
12
Capacity Issue
2

Reported overflow events (showing 94 of 94)

DateVolumeCauseReached waterReceiving water
Dec 24, 2025200 galEquipment Failure——
Sep 12, 2025700 galRoot Intrusion——
Sep 8, 202550 galRoot Intrusion——
Aug 21, 2025150 galOther / Unknown——
Aug 1, 202550 galGrease / FOG——
Jan 11, 2025275 galRoot Intrusion——
Jun 20, 202475 galRoot Intrusion——
May 5, 2024300 galRoot Intrusion——
Sep 28, 202375 galRoot Intrusion——
Jan 9, 20237K galRainfall / FloodingYesStreet/Curb and Gutter
Dec 31, 20226K galRainfall / FloodingYesStreet/Curb and Gutter
Dec 31, 202236K galRainfall / FloodingYesStreet/Curb and Gutter
Dec 31, 20225K galRainfall / FloodingYesStreet/Curb and Gutter
Dec 31, 20229K galRainfall / FloodingYesStreet/Curb and Gutter
Dec 31, 20223K galRainfall / FloodingYesStreet/Curb and Gutter
Dec 31, 20223K galRainfall / FloodingYesStreet/Curb and Gutter
Dec 31, 202250K galRainfall / FloodingYesStreet/Curb and Gutter
Feb 22, 20222K galRoot IntrusionYesSurface Water
Jan 15, 202214 galGrease / FOG—Paved Surface
Dec 27, 20212K galGrease / FOGYesStreet/Curb and Gutter
May 15, 20216K galGrease / FOGYesSurface Water
May 15, 20216K galGrease / FOGYesSurface Water
May 15, 20216K galGrease / FOGYesSurface Water
Dec 10, 2020140 galRoot Intrusion—Separate Storm Drain
Oct 5, 2020400 galEquipment FailureYesDrainage Channel
May 1, 2020200 galGrease / FOG—Separate Storm Drain
Oct 27, 2019150 galGrease / FOG—Paved Surface;Street/Curb and Gutter
Apr 18, 201980 galGrease / FOG—Street/Curb and Gutter
Jan 2, 20185K galEquipment FailureYesDrainage Channel;Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Feb 20, 201720K galCapacity IssueYesPaved Surface;Separate Storm Drain;Street/Curb and Gutter
Mar 28, 2016100 galOther / Unknown—Unpaved surface
Feb 12, 201650 galGrease / FOG—Paved Surface
Oct 28, 2015200 galRoot Intrusion—Paved Surface
Sep 11, 20155 galGrease / FOG—Separate Storm Drain;Street/Curb and Gutter
Sep 11, 2015150 galOther / Unknown—Other (specify below);Unpaved surface
Sep 7, 2015185 galEquipment Failure—Separate Storm Drain;Street/Curb and Gutter
Jul 28, 2015390 galOther / Unknown—Street/Curb and Gutter;Unpaved surface
Jul 27, 20155 galRoot Intrusion—Unpaved surface
Jul 25, 2015225 galRoot Intrusion—Paved Surface
Mar 15, 2015750 galRoot Intrusion—Unpaved surface
Dec 11, 20142K galCapacity IssueYesSurface Water
Aug 15, 20143K galOther / UnknownYesSurface Water
May 30, 20147K galEquipment Failure—Unpaved surface
Feb 28, 2014295 galGrease / FOGYesSeparate Storm Drain
Feb 7, 2014170 galRoot IntrusionYesSeparate Storm Drain
Jan 31, 20145K galEquipment Failure—Unpaved surface
Jan 13, 2014240 galGrease / FOG—Unpaved surface
Oct 25, 2013915 galGrease / FOGYesSeparate Storm Drain
Oct 1, 2013718 galEquipment Failure—Street/Curb and Gutter;Unpaved surface
Sep 2, 201396 galRoot Intrusion—Unpaved surface
Aug 19, 201365 galEquipment Failure—Street/Curb and Gutter
May 23, 2013640 galEquipment Failure—Street/curb and gutter;Unpaved surface
Apr 27, 201316K galOther / Unknown—Separate storm drain;Street/curb and gutter;Surface water
Apr 27, 2013800 galGrease / FOG—Street/curb and gutter
Feb 27, 201344 galOther / Unknown—Unpaved surface
Jan 31, 2013840 galRoot Intrusion—Unpaved surface;Other (specify below)
Jan 20, 2013900 galOther / Unknown—Unpaved surface
Jan 19, 20133K galOther / UnknownYesBuilding or structure;Other paved surface;Separate storm drain;Unpaved surface
Nov 30, 2012300 galRoot Intrusion—Other paved surface;Unpaved surface
Nov 30, 20127K galRoot Intrusion—Separate storm drain
Aug 10, 20121K galGrease / FOG—Unpaved surface;Other (specify below)
Apr 13, 201216K galEquipment FailureYesSeparate storm drain;Surface water;Unpaved surface
Mar 16, 201216K galRoot Intrusion—Building or structure;Separate storm drain
Mar 22, 2011375 galGrease / FOG—Other (specify below)
Dec 26, 20101K galOther / Unknown—Separate storm drain;Street/curb and gutter
Nov 23, 2010350 galRoot Intrusion—Other paved surface;Street/curb and gutter
Sep 25, 2010500 galEquipment Failure—Unpaved surface
Jan 20, 20103K galRainfall / Flooding—Storm drain;Street/curb and gutter
Jan 20, 20103K galRainfall / Flooding—Separate storm drain;Street/curb and gutter
Jan 20, 201024K galRainfall / Flooding—Storm drain
Jan 6, 20102K galGrease / FOG—Other paved surface;Storm drain;Street/curb and gutter;Unpaved surface
Dec 9, 200929 galRoot Intrusion—Building or structure;Unpaved surface;Other (specify below)
Nov 15, 20091K galRoot Intrusion—Street/curb and gutter
Nov 13, 20096K galRoot Intrusion—Other paved surface;Storm drain;Street/curb and gutter;Unpaved surface
Nov 12, 2009330 galRoot Intrusion—Building or structure;Unpaved surface
Nov 10, 20092K galOther / Unknown—Other paved surface;Storm drain;Street/curb and gutter;Unpaved surface
Oct 13, 20099K galRainfall / FloodingYesStorm drain
Jun 7, 2009300 galRoot Intrusion—Storm drain
Feb 24, 200992 galRoot Intrusion—Other (specify below)
Feb 16, 2009375 galOther / Unknown—Other paved surface;Street/curb and gutter
Oct 24, 200875 galRoot Intrusion—Street/curb and gutter
Aug 25, 20082K galRoot Intrusion—Street/curb and gutter
Jul 23, 2008750 galRoot Intrusion—Street/curb and gutter
Jun 23, 2008925 galRoot Intrusion—Storm drain;Street/curb and gutter
May 21, 2008750 galGrease / FOG—Other (specify below)
Mar 16, 2008750 galGrease / FOGYesStorm drain
Jan 13, 2008150 galRoot Intrusion—Street/curb and gutter
Jan 4, 20082K galRainfall / FloodingYesStorm drain
Jan 4, 20082K galRainfall / FloodingYesStorm drain
Jan 4, 20082K galRainfall / FloodingYesStorm drain
Jan 4, 20082K galRainfall / FloodingYesStorm drain
Jan 4, 20082K galRainfall / FloodingYesStorm drain
Sep 10, 20072K galEquipment FailureYesStorm drain;Street/curb and gutter
Jun 7, 2007275 galOther / Unknown—Other paved surface;Street/curb and gutter

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