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California · California (CIWQS)

Central Contra Costa Sanitary District

B
Seldom reaches water
Reported events
701
Total volume
795K gal
Reached waterways
87 (12%)
Reporting since
2007

What caused the overflows

Root Intrusion
499
Other / Unknown
97
Equipment Failure
70
Grease / FOG
34
Rainfall / Flooding
1

Reported overflow events (showing 200 of 701)

DateVolumeCauseReached waterReceiving water
May 12, 2026900 galRoot IntrusionYesWalnut Creek
Apr 23, 20262K galRoot IntrusionYesTice Creek
Apr 5, 2026100 galRoot Intrusion——
Feb 7, 2026672 galRoot Intrusion——
Dec 18, 2025253 galRoot Intrusion——
Dec 13, 2025890 galEquipment FailureYesSan Pablo Creek, San Pablo Reservoir
Dec 9, 202576 galRoot Intrusion——
Dec 3, 2025570 galRoot Intrusion——
Oct 8, 202572 galRoot Intrusion——
Sep 29, 2025242 galEquipment Failure——
Sep 22, 2025510 galRoot Intrusion——
Aug 26, 2025239 galRoot Intrusion——
Jul 19, 2025399 galRoot Intrusion——
Jul 3, 2025104 galRoot Intrusion——
May 12, 2025185 galRoot Intrusion——
Apr 14, 2025180 galRoot IntrusionYesSan Pablo Creek
Apr 1, 2025258 galEquipment FailureYesSan Pablo Creek, San Pablo Reservoir
Feb 7, 20253K galRoot IntrusionYesArroyo del Hombre Creek
Jan 15, 202564 galRoot Intrusion——
Jan 12, 20252K galEquipment Failure——
Nov 23, 202412K galEquipment FailureYesLas Trampas Creek
Oct 9, 2024103 galEquipment Failure——
Oct 5, 202410K galRoot IntrusionYesLauterwausser Creek
Oct 5, 20243K galRoot IntrusionYesLauterwausser Creek
Aug 6, 2024125 galEquipment FailureYesLas Trampas Creek
Aug 4, 2024261 galRoot Intrusion——
Mar 20, 20244K galOther / UnknownYesLauterwasser Creek
Mar 20, 20245K galOther / UnknownYesLauterwasser Creek
Feb 9, 2024155 galRoot Intrusion——
Oct 2, 202369 galGrease / FOG——
Sep 21, 2023211 galOther / Unknown——
Jun 17, 2023155 galRoot Intrusion——
May 20, 202319 galRoot Intrusion—Unpaved surface
May 18, 202356 galRoot Intrusion—Unpaved surface
May 5, 202330 galOther / Unknown—Separate Storm Drain;Street/Curb and Gutter
May 5, 2023220 galEquipment Failure—Unpaved surface
Feb 28, 20233K galGrease / FOG—Paved Surface;Unpaved surface
Jan 14, 2023425 galRoot IntrusionYesDrainage Channel
Dec 14, 2022501 galRoot Intrusion—Unpaved surface
Dec 12, 202265 galGrease / FOG—Paved Surface;Separate Storm Drain
Nov 16, 20221K galEquipment Failure—Separate Storm Drain
Nov 13, 202225 galEquipment Failure—Unpaved surface
Oct 31, 202210 galRoot Intrusion—Paved Surface
Oct 31, 202215 galEquipment Failure—Unpaved surface
Oct 9, 20221 galRoot Intrusion—Paved Surface
Oct 4, 202275 galRoot Intrusion—Unpaved surface
Oct 2, 20225K galEquipment Failure—Other (specify below)
Sep 8, 2022130 galRoot Intrusion—Paved Surface;Unpaved surface
Aug 27, 20223K galRoot IntrusionYesDrainage Channel
Jul 4, 2022118 galGrease / FOG—Separate Storm Drain
Jun 20, 202225 galEquipment Failure—Separate Storm Drain;Street/Curb and Gutter
Jun 2, 202220 galRoot Intrusion—Paved Surface
Mar 31, 2022295 galRoot Intrusion—Unpaved surface
Mar 22, 202224K galEquipment FailureYesDrainage Channel
Mar 11, 20223K galEquipment Failure—Separate Storm Drain
Feb 19, 202212K galEquipment FailureYesSurface Water
Feb 16, 2022629 galRoot Intrusion—Separate Storm Drain;Unpaved surface
Feb 16, 202234 galEquipment Failure—Paved Surface
Feb 3, 20225 galRoot Intrusion—Unpaved surface
Jan 19, 2022160 galEquipment Failure—Separate Storm Drain
Jan 3, 202292 galOther / Unknown—Paved Surface
Dec 14, 202115 galRoot Intrusion—Paved Surface;Unpaved surface
Dec 4, 202159 galRoot Intrusion—Separate Storm Drain
Dec 1, 20219 galRoot Intrusion—Paved Surface
Nov 25, 202115 galRoot Intrusion—Paved Surface
Oct 28, 202180 galRoot Intrusion—Separate Storm Drain;Unpaved surface
Oct 27, 20218 galRoot Intrusion—Paved Surface
Oct 25, 2021840 galRoot IntrusionYesSeparate Storm Drain;Surface Water
Oct 24, 20212K galEquipment FailureYesSeparate Storm Drain;Surface Water
Oct 21, 2021250 galRoot Intrusion—Unpaved surface
Oct 16, 2021620 galRoot Intrusion—Building or Structure;Unpaved surface
Oct 15, 202150 galRoot Intrusion—Unpaved surface
Sep 26, 20211 galRoot Intrusion—Unpaved surface
Sep 3, 2021220 galRoot Intrusion—Unpaved surface
Aug 15, 20219 galRoot Intrusion—Building or Structure
Jun 9, 2021125 galOther / Unknown—Unpaved surface
May 16, 2021945 galRoot Intrusion—Separate Storm Drain
Mar 31, 2021225 galRoot Intrusion—Unpaved surface
Mar 29, 202129 galRoot Intrusion—Unpaved surface
Mar 23, 2021146 galOther / Unknown—Paved Surface
Mar 12, 20212 galRoot Intrusion—Unpaved surface
Mar 6, 202160 galRoot Intrusion—Drainage Channel;Paved Surface
Mar 3, 202110 galRoot Intrusion—Unpaved surface
Feb 7, 2021188 galRoot Intrusion—Unpaved surface
Feb 2, 2021397 galRoot Intrusion—Paved Surface;Unpaved surface
Jan 29, 20213 galRoot Intrusion—Unpaved surface
Jan 18, 202140 galRoot Intrusion—Paved Surface;Unpaved surface
Nov 10, 202022K galOther / UnknownYesDrainage Channel
Nov 7, 202050 galOther / Unknown—Paved Surface
Oct 24, 202068 galGrease / FOG—Paved Surface
Oct 21, 2020207 galRoot Intrusion—Unpaved surface
Oct 17, 2020345 galOther / Unknown—Unpaved surface
Oct 12, 2020280 galRoot Intrusion—Paved Surface;Unpaved surface
Sep 10, 20207 galOther / Unknown—Unpaved surface
Sep 2, 202048 galRoot Intrusion—Separate Storm Drain
Aug 22, 20203K galRoot IntrusionYesDrainage Channel;Unpaved surface
Aug 5, 2020440 galOther / Unknown—Paved Surface;Unpaved surface
Jul 18, 20205 galRoot Intrusion—Unpaved surface
Jun 6, 20202K galEquipment Failure—Unpaved surface
May 26, 202020 galRoot Intrusion—Paved Surface
May 3, 202010 galRoot Intrusion—Unpaved surface
Apr 4, 202010 galRoot Intrusion—Unpaved surface
Mar 2, 202010 galRoot Intrusion—Paved Surface;Separate Storm Drain
Feb 28, 20205 galRoot Intrusion—Other (specify below)
Feb 27, 202052 galRoot Intrusion—Building or Structure;Paved Surface
Feb 22, 20208K galRoot Intrusion—Drainage Channel;Separate Storm Drain;Unpaved surface
Feb 9, 202011K galRoot IntrusionYesDrainage Channel;Unpaved surface
Feb 5, 202046 galRoot IntrusionYesDrainage Channel;Paved Surface;Separate Storm Drain
Jan 24, 202079 galRoot Intrusion—Building or Structure
Jan 17, 2020567 galGrease / FOG—Separate Storm Drain
Jan 11, 202090 galRoot Intrusion—Unpaved surface
Dec 31, 201910 galRoot Intrusion—Paved Surface;Unpaved surface
Dec 30, 2019475 galRoot Intrusion—Paved Surface;Unpaved surface
Oct 25, 20196K galRoot IntrusionYesSeparate Storm Drain
Oct 24, 20192K galRoot Intrusion—Unpaved surface
Oct 16, 2019360 galRoot Intrusion—Separate Storm Drain
Oct 1, 20193 galRoot Intrusion—Paved Surface
Sep 23, 20192 galRoot Intrusion—Paved Surface
Sep 22, 2019199 galOther / Unknown—Unpaved surface
Jul 27, 2019570 galOther / Unknown—Unpaved surface
Jun 27, 2019126 galRoot Intrusion—Unpaved surface
May 28, 201916 galGrease / FOG—Unpaved surface
May 25, 2019660 galGrease / FOGYesSeparate Storm Drain
May 2, 201926 galRoot Intrusion—Drainage Channel
Apr 14, 2019458 galEquipment Failure—Paved Surface;Unpaved surface
Apr 9, 201934 galRoot Intrusion—Separate Storm Drain
Apr 5, 2019244 galRoot Intrusion—Paved Surface;Unpaved surface
Mar 27, 2019400 galOther / UnknownYesSeparate Storm Drain
Mar 19, 201960 galOther / Unknown—Paved Surface;Unpaved surface
Feb 22, 201910 galRoot Intrusion—Unpaved surface
Feb 21, 2019195 galEquipment FailureYesDrainage Channel
Feb 4, 2019942 galRoot IntrusionYesDrainage Channel
Jan 15, 2019228 galEquipment FailureYesDrainage Channel
Dec 20, 2018838 galOther / Unknown—Unpaved surface
Dec 17, 20182 galEquipment Failure—Unpaved surface
Dec 8, 201810 galRoot Intrusion—Paved Surface;Unpaved surface
Dec 2, 201844 galRoot Intrusion—Other (specify below);Paved Surface;Unpaved surface
Oct 30, 2018267 galRoot IntrusionYesDrainage Channel;Separate Storm Drain;Surface Water
Oct 16, 201852 galEquipment Failure—Paved Surface;Unpaved surface
Oct 16, 201850 galEquipment Failure—Paved Surface
Oct 15, 201810 galEquipment Failure—Other (specify below)
Oct 10, 201888 galEquipment Failure—Unpaved surface
Oct 8, 201850 galEquipment Failure—Unpaved surface
Oct 7, 2018185 galEquipment Failure—Unpaved surface
Oct 2, 201830 galRoot Intrusion—Paved Surface;Unpaved surface
Sep 14, 201881 galRoot Intrusion—Street/Curb and Gutter
Aug 20, 2018702 galRoot IntrusionYesDrainage Channel;Unpaved surface
Aug 19, 201857 galRoot Intrusion—Other (specify below)
Aug 17, 201829 galEquipment Failure—Paved Surface
Jul 17, 20185 galRoot Intrusion—Unpaved surface
May 17, 2018275 galRoot Intrusion—Drainage Channel;Unpaved surface
May 9, 201810 galRoot Intrusion—Unpaved surface
Apr 24, 201810 galEquipment Failure—Paved Surface
Mar 21, 2018191 galRoot Intrusion—Unpaved surface
Mar 15, 201890 galRoot Intrusion—Building or Structure
Feb 5, 20183 galOther / Unknown—Separate Storm Drain;Street/Curb and Gutter
Feb 2, 2018180 galRoot IntrusionYesSeparate Storm Drain;Street/Curb and Gutter
Jan 25, 201864 galRoot Intrusion—Street/Curb and Gutter
Jan 15, 201810 galRoot Intrusion—Unpaved surface
Jan 4, 20182K galEquipment Failure—Other (specify below);Unpaved surface
Jan 3, 201860 galRoot Intrusion—Other (specify below)
Dec 31, 2017120 galRoot Intrusion—Unpaved surface
Dec 31, 201745 galRoot Intrusion—Unpaved surface
Dec 11, 201739 galRoot Intrusion—Separate Storm Drain
Nov 20, 2017862 galRoot Intrusion—Combined Storm Drain (Combined CS only);Street/Curb and Gutter;Unpaved surface
Nov 19, 201725 galRoot Intrusion—Separate Storm Drain
Nov 18, 201710 galOther / Unknown—Paved Surface
Nov 13, 201772 galOther / Unknown—Separate Storm Drain
Nov 8, 2017247 galRoot Intrusion—Unpaved surface
Oct 29, 201750 galOther / Unknown—Unpaved surface
Oct 20, 201710 galRoot Intrusion—Unpaved surface
Oct 9, 20172 galOther / Unknown—Street/Curb and Gutter
Aug 21, 2017224 galRoot Intrusion—Separate Storm Drain;Street/Curb and Gutter
Jul 24, 20175 galRoot Intrusion—Paved Surface
Jul 13, 20172K galEquipment Failure—Unpaved surface
Jun 15, 201735 galRoot Intrusion—Paved Surface
Jun 13, 20175 galRoot Intrusion—Unpaved surface
Jun 8, 2017987 galOther / UnknownYesDrainage Channel;Unpaved surface
May 25, 201750 galRoot Intrusion—Paved Surface
May 22, 20175 galRoot Intrusion—Paved Surface
May 8, 201750 galRoot Intrusion—Paved Surface;Unpaved surface
Apr 9, 201710 galRoot Intrusion—Paved Surface
Apr 3, 20171K galRoot Intrusion—Unpaved surface
Mar 30, 2017335 galRoot IntrusionYesDrainage Channel
Mar 13, 20175 galRoot Intrusion—Unpaved surface
Mar 13, 20175 galOther / Unknown—Unpaved surface
Mar 10, 201762 galRoot Intrusion—Unpaved surface
Mar 10, 2017310 galOther / Unknown—Separate Storm Drain
Mar 5, 201779K galRoot IntrusionYesDrainage Channel
Feb 22, 201747 galRoot Intrusion—Unpaved surface
Feb 7, 201740 galRoot Intrusion—Paved Surface
Feb 7, 2017679 galRoot IntrusionYesSurface Water
Jan 24, 201750 galOther / Unknown—Building or Structure
Jan 20, 201720 galOther / Unknown—Unpaved surface
Jan 13, 201730 galRoot Intrusion—Unpaved surface
Jan 12, 2017100 galOther / UnknownYesDrainage Channel
Jan 11, 2017243K galOther / UnknownYesDrainage Channel
Jan 9, 201780 galOther / UnknownYesPaved Surface;Separate Storm Drain;Street/Curb and Gutter
Jan 2, 201720 galRoot Intrusion—Paved Surface
Dec 20, 201615 galRoot Intrusion—Unpaved surface

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