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California · California (CIWQS)

South San Francisco City

B
Seldom reaches water
Reported events
281
Total volume
266K gal
Reached waterways
30 (11%)
Reporting since
2007

What caused the overflows

Equipment Failure
90
Grease / FOG
83
Root Intrusion
76
Other / Unknown
29
Capacity Issue
2
Rainfall / Flooding
1

Reported overflow events (showing 200 of 281)

DateVolumeCauseReached waterReceiving water
Feb 26, 202674 galGrease / FOG——
Feb 5, 2026124 galGrease / FOG——
Jan 26, 202691 galEquipment FailureYesColma Creek
Dec 29, 2025107 galRoot IntrusionYesColma Creek
Sep 9, 2025944 galGrease / FOGYesColma Creek
Mar 26, 202573 galRoot Intrusion——
Jan 7, 2025457 galGrease / FOG——
Dec 4, 2024527 galRoot IntrusionYesColma Creek
Nov 10, 2024116 galEquipment FailureYesColma Creek
Nov 7, 2024135 galRoot Intrusion——
Nov 7, 202489 galGrease / FOG——
Sep 9, 202427 galEquipment FailureYesColma Creek
Sep 3, 2024261 galGrease / FOG——
Apr 10, 2024155 galRoot Intrusion——
Aug 9, 20232K galEquipment FailureYesColma Creek
Jul 31, 202324K galEquipment Failure——
Jan 12, 202379K galEquipment FailureYesOther (specify below)
Dec 1, 2022594 galOther / Unknown—Other (specify below)
May 26, 20226 galRoot Intrusion—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
May 12, 202225 galEquipment Failure—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Mar 9, 2022808 galOther / Unknown—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Feb 8, 2022115 galGrease / FOG—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Jan 25, 2022128 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Jan 24, 202229 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Aug 9, 202120 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Aug 7, 20213 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Jun 17, 20214K galEquipment Failure—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Apr 10, 202116 galEquipment Failure—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Mar 24, 20211 galRoot Intrusion—Paved Surface
Mar 23, 20213 galEquipment Failure—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Feb 21, 20211 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Feb 1, 20214 galGrease / FOG—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Jan 21, 20212 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Jan 16, 2021142 galRoot Intrusion—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Jan 14, 2021109 galRoot Intrusion—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Dec 18, 2020816 galRoot Intrusion—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Nov 17, 20202 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Oct 30, 202093 galRoot Intrusion—Paved Surface;Separate Storm Drain
Oct 10, 202058 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Oct 9, 20201 galEquipment Failure—Paved Surface
Aug 11, 202019 galEquipment Failure—Paved Surface;Street/Curb and Gutter;Unpaved surface
Jul 8, 20205 galOther / Unknown—Paved Surface;Street/Curb and Gutter
Jun 9, 20204 galEquipment Failure—Paved Surface;Street/Curb and Gutter
May 23, 20203 galEquipment Failure—Paved Surface;Street/Curb and Gutter
May 21, 202021 galRoot IntrusionYesPaved Surface;Separate Storm Drain;Street/Curb and Gutter
May 19, 202019 galEquipment Failure—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Apr 9, 20203 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Mar 31, 2020332 galGrease / FOG—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Mar 28, 20201 galEquipment Failure—Paved Surface
Mar 13, 202012 galGrease / FOG—Paved Surface;Street/Curb and Gutter
Feb 29, 20204 galRoot Intrusion—Unpaved surface
Feb 1, 20208 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Jan 31, 202014 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Jan 21, 20205 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Jan 14, 20201 galEquipment Failure—Paved Surface
Jan 6, 2020252 galRoot Intrusion—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Dec 30, 201915 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Dec 23, 2019308 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Dec 16, 20193 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Sep 25, 201912 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Sep 9, 20192 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Sep 5, 20193 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Jul 11, 201911 galGrease / FOG—Paved Surface;Street/Curb and Gutter
Jul 2, 20193 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Jun 24, 201945 galGrease / FOG—Paved Surface;Street/Curb and Gutter
Jun 22, 2019489 galRoot Intrusion—Paved Surface;Street/Curb and Gutter;Unpaved surface
May 22, 2019199 galRoot Intrusion—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
May 20, 20191 galEquipment Failure—Paved Surface;Street/Curb and Gutter
May 1, 201957 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Apr 30, 20191 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Apr 21, 20196 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Mar 29, 20195 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Mar 26, 20199 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Mar 18, 2019288 galRoot Intrusion—Paved Surface
Mar 12, 201998 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Feb 16, 201961 galRoot IntrusionYesPaved Surface;Separate Storm Drain;Street/Curb and Gutter
Feb 6, 20199K galEquipment FailureYesSeparate Storm Drain;Street/Curb and Gutter;Surface Water
Jan 11, 20191 galEquipment Failure—Paved Surface
Jan 2, 201910 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Dec 31, 201810 galGrease / FOG—Paved Surface;Street/Curb and Gutter
Dec 29, 20188 galGrease / FOG—Paved Surface;Street/Curb and Gutter
Nov 15, 2018185 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Nov 4, 201819 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Oct 23, 201833 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Oct 23, 20186 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Oct 6, 2018108 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Sep 30, 20182 galEquipment Failure—Street/Curb and Gutter
Sep 4, 20187 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Aug 23, 20186 galGrease / FOG—Paved Surface;Street/Curb and Gutter
Aug 20, 201815 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Jul 30, 2018307 galEquipment FailureYesSeparate Storm Drain;Street/Curb and Gutter
Jul 18, 20189 galRoot Intrusion—Street/Curb and Gutter
Jul 18, 201841 galEquipment Failure—Street/Curb and Gutter;Unpaved surface
Jun 17, 20186 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Jun 2, 201819 galGrease / FOG—Street/Curb and Gutter
May 28, 20182 galEquipment Failure—Paved Surface;Street/Curb and Gutter
May 14, 201834 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
May 11, 2018305 galGrease / FOG—Street/Curb and Gutter
May 6, 201857 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Apr 30, 201834 galGrease / FOG—Paved Surface;Street/Curb and Gutter
Apr 27, 201811 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Apr 25, 20188 galRoot Intrusion—Building or Structure;Paved Surface;Street/Curb and Gutter
Apr 23, 20185K galEquipment Failure—Unpaved surface
Apr 18, 20183 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Apr 18, 20184 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Apr 9, 20188K galRoot IntrusionYesDrainage Channel;Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Apr 2, 2018130 galRoot Intrusion—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Mar 28, 20181 galEquipment Failure—Paved Surface
Mar 12, 20185 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Mar 7, 2018876 galGrease / FOG—Separate Storm Drain;Street/Curb and Gutter
Mar 4, 20181K galGrease / FOG—Separate Storm Drain
Feb 24, 2018138 galEquipment Failure—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Feb 20, 2018240 galGrease / FOG—Paved Surface;Street/Curb and Gutter
Feb 13, 20185 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Feb 12, 2018700 galRoot IntrusionYesDrainage Channel
Jan 30, 20181 galEquipment Failure—Paved Surface
Jan 22, 201839 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Jan 9, 20183K galEquipment Failure—Building or Structure
Jan 8, 201827 galGrease / FOG—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Jan 8, 201824K galGrease / FOGYesSurface Water
Dec 28, 201716 galGrease / FOG—Paved Surface;Street/Curb and Gutter
Nov 30, 2017295 galGrease / FOG—Paved Surface;Street/Curb and Gutter
Nov 14, 201762 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Nov 6, 201713 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Oct 31, 201735 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Oct 31, 201711 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Oct 17, 201749 galRoot Intrusion—Street/Curb and Gutter
Sep 26, 20171 galEquipment Failure—Street/Curb and Gutter
Sep 8, 201779 galGrease / FOG—Paved Surface;Street/Curb and Gutter
Aug 4, 2017142 galGrease / FOG—Paved Surface;Surface Water
Jul 28, 20175 galGrease / FOG—Paved Surface;Street/Curb and Gutter
Jul 25, 201760 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Jun 29, 20172 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Jun 29, 201743 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Jun 14, 201717 galEquipment Failure—Paved Surface;Street/Curb and Gutter
May 22, 201711 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
May 16, 201721 galEquipment Failure—Paved Surface;Street/Curb and Gutter
May 16, 201750 galEquipment Failure—Street/Curb and Gutter
May 10, 20171 galEquipment Failure—Street/Curb and Gutter
Apr 6, 201793 galEquipment Failure—Building or Structure
Mar 9, 2017375 galGrease / FOGYesPaved Surface;Street/Curb and Gutter
Mar 6, 2017500 galEquipment FailureYesSeparate Storm Drain;Street/Curb and Gutter
Mar 1, 201747 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Feb 16, 20175 galEquipment Failure—Street/Curb and Gutter
Feb 11, 2017225 galGrease / FOG—Separate Storm Drain;Street/Curb and Gutter
Feb 3, 2017130 galEquipment Failure—Building or Structure
Dec 27, 201625 galRoot Intrusion—Paved Surface
Dec 20, 20165 galEquipment Failure—Paved Surface
Dec 15, 201646 galRoot Intrusion—Building or Structure
Dec 6, 2016350 galGrease / FOG—Street/Curb and Gutter
Dec 4, 201610 galRoot Intrusion—Street/Curb and Gutter
Sep 26, 201635 galGrease / FOG—Street/Curb and Gutter
Jul 26, 2016450 galGrease / FOG—Street/Curb and Gutter
Jun 7, 2016415 galEquipment Failure—Building or Structure
Mar 5, 201623K galRainfall / FloodingYesSurface Water
Nov 24, 2015935 galGrease / FOG—Building or Structure
Nov 22, 2015150 galGrease / FOG—Separate Storm Drain
Oct 16, 2015100 galGrease / FOG—Paved Surface
Aug 11, 201576 galEquipment Failure—Building or Structure
Aug 10, 20157K galGrease / FOGYesDrainage Channel
Jul 17, 2015600 galEquipment Failure—Separate Storm Drain
May 31, 20158K galGrease / FOG—Building or Structure
May 11, 2015603 galEquipment Failure—Building or Structure
Mar 13, 201575 galRoot Intrusion—Building or Structure
Aug 28, 2014750 galGrease / FOG—Separate Storm Drain
Jun 12, 2014750 galGrease / FOG—Separate Storm Drain
Feb 11, 2014325 galGrease / FOG—Building or Structure;Separate Storm Drain
Sep 12, 201375 galEquipment Failure—Separate Storm Drain
Sep 9, 2013325 galGrease / FOG—Separate Storm Drain
May 31, 2013200 galRoot Intrusion—Separate Storm Drain
Nov 30, 2012200 galGrease / FOG—Separate storm drain;Unpaved surface
Nov 14, 2012400 galGrease / FOG—Building or structure
Aug 27, 2012100 galEquipment Failure—Other paved surface;Separate storm drain
Mar 31, 2012100 galGrease / FOGYesOther (specify below)
Feb 28, 201270 galGrease / FOG—Separate storm drain
Feb 21, 20121 galRoot Intrusion—Unpaved surface
Dec 22, 201110 galGrease / FOG—Building or structure
Oct 4, 2011800 galEquipment Failure—Separate storm drain
Sep 4, 2011100 galOther / Unknown—Street/curb and gutter
Jul 24, 201125 galOther / Unknown—Building or structure;Street/curb and gutter
Feb 10, 2011100 galOther / Unknown—Unpaved surface
Feb 9, 201150 galRoot Intrusion—Separate storm drain;Street/curb and gutter
Dec 29, 201025 galOther / Unknown—Other paved surface
Nov 8, 2010150 galOther / Unknown—Separate storm drain
Sep 22, 2010100 galGrease / FOG—Building or structure;Other paved surface
Sep 8, 201075 galGrease / FOG—Street/curb and gutter
Aug 24, 20101 galGrease / FOG—Other paved surface
Aug 22, 2010900 galEquipment Failure—Storm drain
Aug 19, 2010200 galRoot Intrusion—Street/curb and gutter
Aug 11, 201040 galGrease / FOG—Street/curb and gutter
Jul 12, 201050 galOther / Unknown—Street/curb and gutter
Jun 30, 201050 galOther / Unknown—Street/curb and gutter
May 6, 201075 galRoot Intrusion—Street/curb and gutter
May 2, 2010200 galOther / Unknown—Storm drain
Apr 13, 2010100 galOther / Unknown—Other paved surface
Apr 2, 201050 galGrease / FOG—Street/curb and gutter
Mar 23, 2010200 galOther / Unknown—Storm drain
Mar 22, 201050 galGrease / FOG—Street/curb and gutter
Mar 17, 2010200 galEquipment Failure—Storm drain
Mar 5, 201020 galOther / Unknown—Street/curb and gutter

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