Every reported sewage spill in Santa Cruz County since 2007
Sewer systems in Santa Cruz County reported 497 spills and 1,133,891 gallons of sewage from 2007 through 2026. More than half of that volume came in a single year.
Every sewer operator in California has to report sanitary sewer spills to the State Water Resources Control Board. Those reports are public, one row per spill, with a date, a location, an estimated volume and whether the sewage reached a creek, a storm drain or the ocean. We pulled every record the state tags as Santa Cruz County: 498 spill records starting in 2007.
Source: State Water Board sanitary sewer spill records (CIWQS) · Data: cruzlens.json, computed.json · Code: CruzLens
Show the data (20 rows)
| Year | Gallons (Santa Cruz County systems) |
|---|---|
| 2007 | 1,590 |
| 2008 | 6,955 |
| 2009 | 47,401 |
| 2010 | 10,370 |
| 2011 | 138,005 |
| 2012 | 44,178 |
| 2013 | 7,815 |
| 2014 | 81,927 |
| 2015 | 5,042 |
| 2016 | 11,382 |
| 2017 | 83,830 |
| 2018 | 6,751 |
| 2019 | 27,201 |
| 2020 | 5,296 |
| 2021 | 15,590 |
| 2022 | 3,031 |
| 2023 | 602,965 |
| 2024 | 8,026 |
| 2025 | 6,419 |
| 2026 | 20,117 |
Most years are small. Then a storm arrives.
From 2007 through 2026, Santa Cruz County’s sewer systems reported 497 spills totalling 1,133,891 gallons. 81% of that volume reached surface water.
The volume is extremely lumpy. In a typical year, a dozen to a few dozen spills add up to a few thousand to a few tens of thousands of gallons: 10 spills and 6,419 gallons in 2025. Then came the winter storms of early 2023. On January 16, 2023 alone, three of the five largest spills on record added up to 592,898 gallons, led by 376,764 gallons at the county’s Da Porath Facility. In all, 2023 produced 602,965 gallons, 53% of everything the county’s systems reported in nearly twenty years.
Source: State Water Board sanitary sewer spill records (CIWQS) · Data: cruzlens.json · Code: CruzLens
Show the data (20 rows)
| Year | Spills | Gallons | Gallons reaching surface water |
|---|---|---|---|
| 2007 | 13 | 1,590 | 200 |
| 2008 | 20 | 6,955 | 880 |
| 2009 | 44 | 47,401 | 43,520 |
| 2010 | 29 | 10,370 | 8,355 |
| 2011 | 38 | 138,005 | 132,215 |
| 2012 | 43 | 44,178 | 20,150 |
| 2013 | 41 | 7,815 | 2,192 |
| 2014 | 46 | 81,927 | 28,345 |
| 2015 | 22 | 5,042 | 3,385 |
| 2016 | 35 | 11,382 | 9,365 |
| 2017 | 26 | 83,830 | 57,015 |
| 2018 | 19 | 6,751 | 872 |
| 2019 | 16 | 27,201 | 21,104 |
| 2020 | 10 | 5,296 | 0 |
| 2021 | 26 | 15,590 | 7,177 |
| 2022 | 17 | 3,031 | 676 |
| 2023 | 21 | 1,402,965 | 1,353,425 |
| 2024 | 17 | 8,026 | 4,645 |
| 2025 | 10 | 6,419 | 4,518 |
| 2026 | 5 | 20,117 | 19,650 |
The number of spills, unlike the volume, has fallen: 46 in 2014 against 10 in 2025. A count of spills says more about pipe maintenance; the volume says more about storms.
The biggest spill on the list isn’t in Santa Cruz County
The largest record in the state’s Santa Cruz County data is an 800,000-gallon spill on 2023-03-12 at the Pajaro River At Highway 1, reported by the Pajaro County Sanitation District Collection System. That district serves Pajaro, which is across the river in Monterey County. The spill happened during the March 2023 Pajaro River flooding, and the source tags it Santa Cruz County. We list it here and leave it out of every Santa Cruz total in this post; with it included, the totals would be 1,933,891 gallons and 2023 would look even more extreme.
Which systems
Source: State Water Board sanitary sewer spill records (CIWQS) · Data: cruzlens.json · Code: CruzLens
Show the data (13 rows)
| System | Spills | Gallons | Reached surface water |
|---|---|---|---|
| Santa Cruz County CS | 188 | 813,472 | 716,404 |
| Santa Cruz City CS | 123 | 91,988 | 48,092 |
| Scotts Valley CS | 52 | 41,145 | 14,562 |
| UC Santa Cruz CS | 51 | 3,166 | 0 |
| Watsonville CS | 31 | 88,251 | 76,987 |
| Freedom Co Sanitation District CS | 18 | 6,143 | 606 |
| Boulder Crk Golf & Cntry Club CS | 15 | 43,191 | 22,468 |
| Bear Creek Estates CS | 9 | 35,000 | 34,350 |
| Big Basin CS | 5 | 9,720 | 4,170 |
| Rolling Woods Subdivision CS | 2 | 765 | 30 |
| Davenport CS | 2 | 1,010 | 0 |
| Salsipuedes Sanitary District Collection System | 1 | 40 | 20 |
| Pajaro County Sanitation District Collection System | 1 | 800,000 | 800,000 |
The county-run Santa Cruz County collection system reported 188 spills and 72% of the county’s spilled volume, much of it from January 2023. The City of Santa Cruz reported 123 spills with 91,988 gallons. UC Santa Cruz reported 51 spills, none of which reached surface water. Systems serve very different numbers of people and miles of pipe, so these totals are not a ranking of how well each is run.
Storms, as far as the records say
Only 19 Santa Cruz County records are flagged as storm-associated, but they carry 58% of the county’s spilled volume. That is a lower bound: 498 records in total, and the storm field is blank on 240 of them, mostly older reports.
Spills near the coast can close beaches, and wet-weather bacteria are the subject of our post on beaches after rain. Every spill in this post is on the CruzLens map, with a link to its record.
Methods
- Source. State Water Resources Control Board sanitary sewer spill records (CIWQS), via the Water Boards’ public spill map service, filtered to
COUNTY='Santa Cruz', retrieved October 11, 2026 (UTC) by CruzLens. - Grouping. By spill start year and by the collection system named in the report. Gallons are the operator’s estimate of total volume spilled; "reached surface water" is the operator’s estimate of the part that reached a water body or a drainage channel.
- Santa Cruz totals exclude the one Pajaro County Sanitation District record (
scripts/derive_from_findings.py).
Limits
Spill reports are self-reported by sewer operators under statewide orders (2006-0003-DWQ, then 2022-0103-DWQ). Volumes are estimates. Spills from private laterals, the pipe between a house and the street, are mostly not included. Older records can be revised. 2026 covers only part of the year.
Data and code
Every number and chart in this post is generated from these files:
The projects that collected the data: