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California · California (CIWQS)

Napa Sanitation District

B
Seldom reaches water
Reported events
977
Total volume
1.0M gal
Reached waterways
100 (10%)
Reporting since
2007

What caused the overflows

Root Intrusion
513
Equipment Failure
236
Other / Unknown
87
Grease / FOG
59
Capacity Issue
46
Rainfall / Flooding
36

Reported overflow events (showing 200 of 977)

DateVolumeCauseReached waterReceiving water
Apr 21, 2026555 galOther / UnknownYesThe Napa River
Feb 10, 2026120 galOther / UnknownYesThe Napa River
Jan 30, 202670 galEquipment Failure——
Feb 4, 202515K galRainfall / FloodingYesThe Napa River
Feb 4, 20252K galRainfall / FloodingYesThe Napa River
Feb 4, 20252K galRainfall / FloodingYesThe Napa River
Feb 4, 2025910 galRainfall / FloodingYesThe Napa River
Feb 4, 20257K galRainfall / FloodingYesNapa River
Dec 4, 20242K galGrease / FOG——
Sep 14, 2024360 galRoot Intrusion——
Aug 10, 2024383 galEquipment FailureYesWater Conveyance System
Mar 15, 202454 galOther / Unknown——
Jan 18, 202495 galEquipment Failure——
Sep 28, 202378 galOther / Unknown——
Sep 26, 202360 galRoot Intrusion——
May 25, 20233 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
May 9, 202318 galEquipment Failure—Paved Surface;Street/Curb and Gutter;Unpaved surface
May 7, 20232 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Apr 24, 202327 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Apr 17, 202342 galEquipment Failure—Paved Surface;Street/Curb and Gutter;Unpaved surface
Apr 10, 20231 galRoot Intrusion—Paved Surface
Apr 10, 2023121 galRoot Intrusion—Unpaved surface
Apr 3, 2023196 galRoot Intrusion—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Mar 27, 202314 galRoot Intrusion—Unpaved surface
Mar 10, 20234K galRainfall / FloodingYesPaved Surface;Separate Storm Drain;Street/Curb and Gutter;Surface Water
Mar 5, 20231 galEquipment Failure—Street/Curb and Gutter
Feb 14, 20232 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Feb 10, 20236 galRoot Intrusion—Unpaved surface
Feb 4, 20232 galRoot Intrusion—Paved Surface;Unpaved surface
Jan 20, 2023261 galRoot Intrusion—Unpaved surface
Jan 9, 20237K galRainfall / FloodingYesPaved Surface;Separate Storm Drain;Street/Curb and Gutter
Dec 21, 20223 galRoot Intrusion—Paved Surface;Unpaved surface
Dec 7, 202211 galEquipment Failure—Unpaved surface
Nov 20, 20224 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Nov 1, 20221 galRoot Intrusion—Paved Surface
Oct 5, 202211 galRoot Intrusion—Unpaved surface
Sep 27, 20224 galGrease / FOG—Paved Surface;Street/Curb and Gutter
Sep 24, 202214 galEquipment Failure—Unpaved surface
Aug 22, 20224 galEquipment Failure—Unpaved surface
Aug 19, 20221 galRoot Intrusion—Paved Surface
Jul 5, 202281 galRoot Intrusion—Paved Surface
Jun 23, 20223 galEquipment Failure—Paved Surface;Unpaved surface
Jun 15, 20221 galRoot Intrusion—Paved Surface;Unpaved surface
May 21, 20223 galEquipment Failure—Paved Surface;Unpaved surface
May 16, 20223 galRoot Intrusion—Paved Surface;Unpaved surface
May 15, 20222 galRoot Intrusion—Unpaved surface
Apr 1, 202253 galRoot Intrusion—Unpaved surface
Mar 25, 20224 galRoot Intrusion—Unpaved surface
Mar 24, 202223 galRoot Intrusion—Unpaved surface
Mar 20, 20226 galRoot Intrusion—Unpaved surface
Feb 27, 202241 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Feb 4, 202230 galEquipment Failure—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Feb 3, 20221 galEquipment Failure—Paved Surface
Jan 18, 20223 galRoot Intrusion—Paved Surface;Unpaved surface
Jan 13, 2022314 galRoot Intrusion—Unpaved surface
Dec 30, 20211 galRoot Intrusion—Paved Surface
Dec 19, 2021427 galGrease / FOG—Paved Surface;Separate Storm Drain
Dec 11, 202144 galGrease / FOG—Street/Curb and Gutter;Unpaved surface
Dec 8, 2021411 galOther / Unknown—Paved Surface;Unpaved surface
Dec 5, 20211 galRoot Intrusion—Paved Surface
Nov 20, 20211 galOther / Unknown—Paved Surface
Nov 18, 20211 galOther / Unknown—Paved Surface;Street/Curb and Gutter
Oct 24, 20219K galCapacity IssueYesSeparate Storm Drain
Oct 12, 202114 galEquipment Failure—Unpaved surface
Sep 26, 202111 galGrease / FOG—Unpaved surface
Sep 21, 202111 galEquipment Failure—Building or Structure;Paved Surface;Unpaved surface
Sep 9, 202111 galEquipment Failure—Paved Surface;Unpaved surface
Aug 13, 202121 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Aug 12, 20211 galEquipment Failure—Paved Surface
Aug 7, 20219 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Jun 26, 20217 galEquipment Failure—Unpaved surface
May 31, 20211 galEquipment Failure—Paved Surface
May 1, 202130 galRoot Intrusion—Unpaved surface
May 1, 20212 galEquipment Failure—Paved Surface;Unpaved surface
Apr 10, 20215 galGrease / FOG—Paved Surface
Mar 23, 202118 galOther / Unknown—Paved Surface;Unpaved surface
Mar 19, 20218 galEquipment Failure—Paved Surface
Mar 12, 20218 galRoot Intrusion—Paved Surface;Unpaved surface
Mar 10, 2021560 galOther / UnknownYesPaved Surface;Separate Storm Drain;Street/Curb and Gutter
Mar 2, 2021105 galOther / Unknown—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Feb 20, 2021141 galRoot Intrusion—Paved Surface;Street/Curb and Gutter;Unpaved surface
Feb 14, 202128 galRoot Intrusion—Unpaved surface
Feb 8, 20212 galEquipment Failure—Paved Surface;Street/Curb and Gutter;Unpaved surface
Jan 18, 20215 galEquipment Failure—Unpaved surface
Jan 17, 202118 galRoot Intrusion—Paved Surface;Unpaved surface
Jan 16, 20212 galRoot Intrusion—Paved Surface
Jan 13, 202189 galRoot Intrusion—Unpaved surface
Jan 11, 202112 galRoot Intrusion—Paved Surface;Unpaved surface
Dec 28, 20202 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Dec 19, 202076 galEquipment Failure—Separate Storm Drain;Street/Curb and Gutter;Unpaved surface
Nov 25, 202011 galRoot Intrusion—Paved Surface;Unpaved surface
Nov 9, 20204 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Nov 2, 202086 galRoot Intrusion—Paved Surface;Unpaved surface
Nov 2, 202012 galRoot Intrusion—Unpaved surface
Sep 27, 20203 galRoot Intrusion—Unpaved surface
Sep 23, 20206 galOther / Unknown—Paved Surface
Sep 4, 20206 galRoot Intrusion—Unpaved surface
Aug 21, 202045 galOther / Unknown—Paved Surface;Street/Curb and Gutter
Aug 19, 202040 galEquipment Failure—Unpaved surface
Aug 19, 20209 galRoot Intrusion—Paved Surface;Street/Curb and Gutter;Unpaved surface
Aug 15, 202011 galRoot Intrusion—Paved Surface;Unpaved surface
Aug 9, 20202 galEquipment Failure—Unpaved surface
Jul 26, 202049 galRoot Intrusion—Unpaved surface
Jul 22, 20203 galRoot Intrusion—Unpaved surface
Jul 1, 202083 galGrease / FOG—Paved Surface;Separate Storm Drain;Street/Curb and Gutter
Jun 19, 20201 galRoot Intrusion—Paved Surface
Jun 8, 20203 galRoot Intrusion—Unpaved surface
May 26, 20204 galRoot Intrusion—Unpaved surface
May 21, 20201 galRoot Intrusion—Paved Surface
Apr 3, 20206 galEquipment Failure—Paved Surface;Street/Curb and Gutter;Unpaved surface
Feb 27, 20201 galEquipment Failure—Paved Surface
Feb 19, 202010 galEquipment Failure—Unpaved surface
Feb 8, 20205 galRoot Intrusion—Paved Surface
Jan 27, 202015 galEquipment Failure—Paved Surface;Unpaved surface
Jan 22, 20201 galEquipment Failure—Paved Surface
Jan 16, 2020450 galEquipment Failure—Paved Surface
Jan 6, 20202K galOther / UnknownYesPaved Surface;Separate Storm Drain;Street/Curb and Gutter
Jan 3, 202044 galGrease / FOG—Unpaved surface
Dec 29, 201928 galRoot Intrusion—Unpaved surface
Dec 26, 20198 galRoot Intrusion—Paved Surface;Unpaved surface
Dec 21, 201917 galRoot Intrusion—Unpaved surface
Dec 21, 201918 galEquipment Failure—Unpaved surface
Nov 23, 20196 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Oct 30, 20191 galGrease / FOG—Paved Surface
Oct 28, 201914 galRoot Intrusion—Unpaved surface
Oct 15, 201910 galRoot Intrusion—Unpaved surface
Oct 13, 201927 galEquipment Failure—Paved Surface;Unpaved surface
Oct 7, 20195 galRoot Intrusion—Paved Surface;Unpaved surface
Oct 3, 20195 galEquipment Failure—Unpaved surface
Oct 1, 20192 galGrease / FOG—Paved Surface
Sep 20, 20193 galEquipment Failure—Unpaved surface
Sep 17, 201912 galRoot Intrusion—Paved Surface;Street/Curb and Gutter;Unpaved surface
Aug 22, 20194 galRoot Intrusion—Paved Surface
Jul 29, 201916 galRoot Intrusion—Unpaved surface
Jul 12, 20199 galRoot Intrusion—Street/Curb and Gutter
Jul 11, 201918 galRoot Intrusion—Unpaved surface
Jul 2, 201929 galOther / Unknown—Street/Curb and Gutter;Unpaved surface
Jun 25, 201956 galEquipment Failure—Unpaved surface
Jun 25, 201913 galRoot Intrusion—Unpaved surface
Jun 2, 201947 galEquipment Failure—Unpaved surface
May 13, 201924 galGrease / FOG—Paved Surface;Street/Curb and Gutter
Apr 26, 20193 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Apr 3, 2019105 galRoot Intrusion—Paved Surface;Separate Storm Drain;Street/Curb and Gutter;Unpaved surface
Apr 1, 201910 galRoot Intrusion—Paved Surface;Unpaved surface
Mar 31, 201950 galEquipment Failure—Street/Curb and Gutter
Mar 29, 2019138 galOther / UnknownYesPaved Surface;Separate Storm Drain;Street/Curb and Gutter
Mar 28, 20192 galEquipment Failure—Building or Structure
Mar 26, 2019390 galEquipment FailureYesSeparate Storm Drain;Street/Curb and Gutter
Mar 25, 201918 galOther / Unknown—Unpaved surface
Mar 24, 201936 galRoot Intrusion—Separate Storm Drain;Street/Curb and Gutter;Unpaved surface
Mar 24, 201915 galRoot Intrusion—Paved Surface;Street/Curb and Gutter
Mar 24, 201958 galRoot Intrusion—Paved Surface;Street/Curb and Gutter;Unpaved surface
Mar 23, 201925 galRoot Intrusion—Building or Structure
Mar 21, 20194 galRoot Intrusion—Street/Curb and Gutter
Mar 17, 201911 galRoot Intrusion—Unpaved surface
Mar 16, 201911 galGrease / FOG—Unpaved surface
Mar 16, 20191 galRoot Intrusion—Paved Surface
Mar 12, 20191 galEquipment Failure—Unpaved surface
Mar 12, 20191 galRoot Intrusion—Unpaved surface
Mar 11, 20196 galRoot Intrusion—Unpaved surface
Feb 26, 20193K galRainfall / FloodingYesSeparate Storm Drain
Feb 26, 20194K galRainfall / FloodingYesSeparate Storm Drain
Feb 26, 20195K galRainfall / FloodingYesSeparate Storm Drain
Feb 26, 201987 galRainfall / FloodingYesSeparate Storm Drain
Feb 26, 201934K galRainfall / FloodingYesSeparate Storm Drain
Feb 26, 2019103K galRainfall / FloodingYesSeparate Storm Drain
Feb 26, 201919K galRainfall / FloodingYesSeparate Storm Drain
Feb 20, 20191 galRoot Intrusion—Paved Surface
Feb 20, 201943 galRoot Intrusion—Street/Curb and Gutter;Unpaved surface
Feb 14, 201915K galRainfall / FloodingYesSeparate Storm Drain
Feb 14, 20192K galRainfall / FloodingYesSeparate Storm Drain
Feb 14, 20192K galRainfall / FloodingYesSeparate Storm Drain
Feb 14, 20191K galRainfall / FloodingYesSeparate Storm Drain
Feb 14, 2019111 galRainfall / FloodingYesSeparate Storm Drain
Feb 14, 201932K galRainfall / FloodingYesSeparate Storm Drain
Feb 5, 20191 galEquipment Failure—Unpaved surface
Jan 28, 2019138 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Jan 24, 20194 galEquipment Failure—Unpaved surface
Jan 16, 201952 galRainfall / FloodingYesDrainage Channel;Separate Storm Drain
Jan 16, 2019227 galRainfall / FloodingYesDrainage Channel;Separate Storm Drain
Jan 16, 20193K galRainfall / FloodingYesDrainage Channel;Separate Storm Drain
Jan 16, 20193K galCapacity IssueYesSeparate Storm Drain
Dec 24, 20185 galRoot Intrusion—Unpaved surface
Dec 22, 201872 galEquipment Failure—Street/Curb and Gutter
Dec 20, 201820 galRoot Intrusion—Street/Curb and Gutter
Dec 19, 20182K galEquipment FailureYesSeparate Storm Drain
Dec 15, 201820 galRoot Intrusion—Street/Curb and Gutter
Dec 15, 201888 galEquipment Failure—Street/Curb and Gutter
Dec 11, 20181 galRoot Intrusion—Street/Curb and Gutter
Dec 10, 20183 galRoot Intrusion—Street/Curb and Gutter
Dec 8, 201825 galEquipment Failure—Paved Surface;Street/Curb and Gutter
Dec 5, 201822 galRoot Intrusion—Street/Curb and Gutter
Dec 4, 201812 galRoot Intrusion—Unpaved surface
Dec 1, 201835 galRoot Intrusion—Street/Curb and Gutter
Nov 27, 20185 galRoot Intrusion—Unpaved surface
Nov 23, 201850 galEquipment FailureYesPaved Surface;Street/Curb and Gutter;Surface Water
Nov 12, 20181 galRoot Intrusion—Unpaved surface
Nov 7, 20181 galRoot Intrusion—Paved Surface
Nov 4, 20185 galRoot Intrusion—Unpaved surface
Nov 3, 201835 galRoot Intrusion—Paved Surface;Unpaved surface

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