EPA data · Water quality
America's Dirtiest Beaches (2026)
Every swimming advisory and closure that states reported to the US Environmental Protection Agency for 2024, at 3,135 monitored ocean, bay and Great Lakes beaches in the 50 states: which beaches spent the most days unsafe for swimming, which states had the highest share, and why.
By Laurence Tuchin, Founder, SurfSpotGuide
Share of swim-season beach days under a swimming advisory or closure at 3,135 monitored beaches in the 50 states in 2024, according to EPA BEACON data.
- of 3,135 monitored beaches had at least one advisory
- 1,325
- of Louisiana's swim-season beach days were under advisory, the highest share of any state
- 51.4%
- of the beaches with the most advisory days were in California
- 5 of 6
Key takeaways
- 01US coastal and Great Lakes beaches in the 50 states were under a swimming advisory or closure for 5.8% of their 2024 swim-season days, according to SurfSpotGuide analysis of US EPA BEACON data.
- 021,325 of the 3,135 monitored coastal and Great Lakes beaches in the 50 states (42.3%) had at least one swimming advisory or closure in 2024, according to SurfSpotGuide analysis of US EPA BEACON data.
- 03Puerco Beach, Los Angeles County, California, spent more days under a swimming advisory than any other US beach in 2024 that wasn't under a standing advisory: 241 of 365 days (66%), according to SurfSpotGuide analysis of US EPA BEACON data.
- 04Louisiana's beaches were under advisory for 51.4% of their 2024 swim-season days, the highest share of any state, according to SurfSpotGuide analysis of US EPA BEACON data.
- 05California recorded the most beach-days under a swimming advisory of any state in 2024: 11,377 (13.6% of its beaches' swim-season days), according to SurfSpotGuide analysis of US EPA BEACON data.
- 06Elevated bacteria were cited in 65% of swimming advisories and closures at US coastal and Great Lakes beaches in 2024, and heavy rain in 48% (one advisory can cite both), according to SurfSpotGuide analysis of US EPA BEACON data.
Which US beach has the most swimming advisories?
Puerco Beach, Los Angeles County, California, spent 241 of its 365 swim-season days in 2024 under a swimming advisory (66%), more than any other US beach not under a standing advisory. The 20 beaches with the most advisory days are below.
| # | Beach | Days under advisory | % of swim season | Advisories | Main cause |
|---|---|---|---|---|---|
| 1 | Puerco BeachLos Angeles County, California · sampling site SMB-1-12 | 241 of 365 | 66% | 22 | Elevated bacteria |
| 2 | Newport BayOrange County, California · sampling site BNB34 | 194 of 365 | 53.2% | 39 | Elevated bacteria |
| 3 | Silver Strand State BeachSan Diego County, California · sampling site IB-068 | 179 of 365 | 49% | 11 | Elevated bacteria |
| 4 | Malibu Lagoon State BeachLos Angeles County, California · sampling site SMB-MC-2 | 177 of 365 | 48.5% | 23 | Elevated bacteria |
| 5 | RUTH1Cameron Parish, Louisiana | 176 of 183 | 96% | 2 | Elevated bacteria |
| 6 | Doheny State BeachOrange County, California · sampling site DSB4Z | 172 of 365 | 47.1% | 25 | Elevated bacteria |
| 7 | South BeachMonroe County, Florida | 169 of 244 | 69.3% | 5 | Elevated bacteria |
| 8 | Pillar Point HarborSan Mateo County, California · sampling site Pillar Point #9 | 167 of 365 | 45.8% | 14 | Elevated bacteria |
| 9 | Marlin Park, Foster CitySan Mateo County, California · sampling site Marlin Park | 165 of 213 | 77.5% | 8 | Elevated bacteria |
| 10 | Lakeshore ParkSan Mateo County, California · sampling site Lakeshore Park Rec Center | 163 of 365 | 44.7% | 2 | Elevated bacteria |
| 11 | Coronado City beachesSan Diego County, California · sampling site IB-080 | 158 of 365 | 43.3% | 27 | Elevated bacteria |
| 12 | Kalapaki BeachKauai County, Hawaii | 158 of 365 | 43.2% | 5 | Rainfall (preemptive) |
| 13 | Santa Monica State BeachLos Angeles County, California · sampling site DPH 105B | 150 of 365 | 41.1% | 24 | Elevated bacteria |
| 14 | Escondido BeachLos Angeles County, California · sampling site SMB-1-8 | 149 of 365 | 40.8% | 17 | Elevated bacteria |
| 15 | HOLLY6Cameron Parish, Louisiana | 149 of 183 | 81.2% | 3 | Elevated bacteria |
| 16 | HOLLY3Cameron Parish, Louisiana | 148 of 183 | 80.9% | 4 | Elevated bacteria |
| 17 | MART1Cameron Parish, Louisiana | 148 of 183 | 80.9% | 1 | Elevated bacteria |
| 18 | Oyster Point MarinaSan Mateo County, California · sampling site Oyster Point Marina | 139 of 365 | 38.1% | 5 | Elevated bacteria |
| 19 | Will Rogers State BeachLos Angeles County, California · sampling site SMB-2-2 | 137 of 365 | 37.5% | 24 | Elevated bacteria |
| 20 | Niumalu Beach ParkKauai County, Hawaii | 133 of 365 | 36.5% | 2 | Rainfall (preemptive) |
Source: SurfSpotGuide analysis of US EPA BEACON data, 2024. California reports each sampling site as its own beach, so one stretch of sand can appear more than once. Top 50 as CSV.
US territories, ranked separately because they sample a few short beaches very often: Togcha Beach aka Hågat Beach, Guam (365 of 365 days); Trinchera Beach, East Hagåtña Bay, Guam (305 of 365 days); West Hagåtña Beach, Guam (262 of 365 days); Beach at Piti Bay, Guam (248 of 365 days); Toguan Bay, Guam (232 of 365 days).
Which state has the dirtiest beaches?
By share of swim-season days under advisory, Louisiana (51.4%), Ohio (16.8%) and California (13.6%) ranked highest in 2024. States test their beaches differently, though: more sampling finds more problems, so the table shows how often each state sampled.
- Louisiana51.4%
- Ohio16.8%
- California13.6%
- Georgia12.4%
- Indiana9.3%
- Wisconsin8.8%
- New York7.1%
- Hawaii6.9%
- Mississippi6.5%
- Washington6.2%
- Texas4.2%
- Florida3.1%
- Connecticut3.1%
- Minnesota3.1%
- Maine3%
States with at least 10 monitored beaches. Sampling effort differs by state; see the table.
Show the numbers
| State | Share of beach-days under advisory | Monitored beaches | Beaches with an advisory | Median samples per beach |
|---|---|---|---|---|
| Louisiana | 51.4% | 21 | 21 | 28 |
| Ohio | 16.8% | 76 | 67 | 27 |
| California | 13.6% | 252 | 202 | 51 |
| Georgia | 12.4% | 28 | 18 | 48 |
| Indiana | 9.3% | 24 | 20 | 97 |
| Wisconsin | 8.8% | 117 | 91 | 30 |
| New York | 7.1% | 327 | 157 | 17 |
| Hawaii | 6.9% | 179 | 164 | 3 |
| Mississippi | 6.5% | 21 | 15 | 59 |
| Washington | 6.2% | 66 | 12 | 14 |
| Texas | 4.2% | 63 | 57 | 89 |
| Florida | 3.1% | 232 | 84 | 26 |
| Connecticut | 3.1% | 71 | 48 | 15 |
| Minnesota | 3.1% | 38 | 17 | 15 |
| Maine | 3% | 65 | 43 | 15 |
| Massachusetts | 2.6% | 572 | 123 | 13 |
| Virginia | 2.5% | 47 | 33 | 18 |
| Maryland | 2.3% | 58 | 12 | 13 |
| Michigan | 1.1% | 197 | 62 | 0 |
| South Carolina | 1.1% | 21 | 5 | 50 |
| Alabama | 1% | 24 | 9 | 29 |
| North Carolina | 0.9% | 224 | 18 | 33 |
| Rhode Island | 0.5% | 68 | 9 | 9 |
| Oregon | 0.5% | 24 | 3 | 40 |
| New Jersey | 0.1% | 212 | 20 | 17 |
| Delaware | 0.1% | 22 | 3 | 18 |
| Alaska | 0% | 10 | 0 | 9 |
| New Hampshire | 0% | 16 | 8 | 12 |
Source: SurfSpotGuide analysis of US EPA BEACON data, 2024. Not ranked: Illinois (no advisories reported to the EPA for 2024). All states and territories as CSV.
Which states have the cleanest beaches?
By the same measure, New Hampshire (0%), Alaska (0%) and Delaware (0.1%) had the smallest share of swim-season days under advisory in 2024. A low share can also mean less testing, so check how often each state sampled.
- New Hampshire0%
- Alaska0%
- Delaware0.1%
- New Jersey0.1%
- Oregon0.5%
- Rhode Island0.5%
- North Carolina0.9%
- Alabama1%
- South Carolina1.1%
- Michigan1.1%
States with at least 10 monitored beaches.
Why do beaches get swimming advisories?
Mostly bacteria. Elevated bacteria levels were cited in 65% of the 6,652 advisories and closures at 50-state beaches in 2024, and heavy rain, which washes runoff into the water, in 48%; one advisory can cite both. For 43% the source of the pollution was not identified.
- Storm (wet-weather) runoff3,411 advisories
- Dry-weather runoff197 advisories
- Combined sewer overflow142 advisories
- Septic systems32 advisories
One advisory can name more than one source. Source: US EPA BEACON, 2024.
Which beaches had long-running swimming advisories?
7 beaches were under a single advisory lasting 180 days or more in 2024, a standing warning not to swim rather than a response to one bad test.
- American Memorial Park Drainage, Northern Mariana Islands: 337 of 365 swim-season days
- Kings Ferry, Chatham County, Georgia: 213 of 213 swim-season days
- Jekyll Clam Creek Beach, Glynn County, Georgia: 213 of 213 swim-season days
- St. Andrews Beach (Jekyll), Glynn County, Georgia: 213 of 213 swim-season days
- Pacifica State Beach, San Mateo County, California: 181 of 365 swim-season days
- Border Field State Park, San Diego County, California: 181 of 365 swim-season days
- Imperial Beach municipal beach, other, San Diego County, California: 181 of 365 swim-season days
Are US beaches getting cleaner?
Three seasons can't show a trend. The share of swim-season days under advisory at 50-state beaches was 6.3% in 2023, 5.8% in 2024, 6.2% in 2025 (provisional). Rainfall moves these numbers a lot from year to year.
Definitions
- Swimming advisory or closure
- A notice from a state or local health agency warning people not to swim (advisory) or closing the water (closure), usually because bacteria levels exceed the safe limit or are expected to after rain.
- Days under advisory
- Days in the beach's swim season covered by at least one advisory or closure. Overlapping notices at several sampling sites on one beach count once.
- Standing advisory
- A single advisory lasting 180 days or more, often posted at beaches near storm drains, lagoons or known sewage sources.
- Monitored beach
- A coastal or Great Lakes beach with a swim season that was sampled at least once that year.
Methodology
States and territories report every beach advisory and closure to the EPA under the BEACH Act. We downloaded the national reports for each year and kept ocean, bay, sound and Great Lakes beaches. For each beach we counted the days in its swim season covered by any advisory or closure, so two notices on the same day count once. The EPA's own per-beach totals add overlapping notices together, which is why some exceed a full season.
The ranking excludes beaches under a standing advisory, which are listed separately, and ranks the territories separately. 2024 is the latest complete season; the EPA updates its data as states resubmit, so figures can change slightly.
The biggest caveat: States set their own sampling frequency, swim season, and advisory policy (some post rain-based preemptive advisories without sampling, some use models). More sampling finds more exceedances, so a state with more advisory days does not necessarily have dirtier water. Compare states with care and show their sampling effort.
Sources
- US EPA BEACON 2.0 (Beach Advisory and Closing On-line Notification): national reports, 2023–2025, downloaded 2026-10-16
Frequently asked questions
Is it safe to swim at a beach under an advisory?
Health agencies advise against it. Bacteria at advisory levels raise the risk of stomach illness, skin rashes and ear, eye and respiratory infections. Check the local health department's beach page before you go, and stay out of the water for a day or two after heavy rain.
Why do some beaches have advisories after rain?
Rain washes runoff from streets, storm drains and sometimes sewer overflows into the sea. Many states post precautionary advisories after heavy rain without waiting for a test result.
How often is this data updated?
Once a year, after states finish reporting the previous season to the EPA, usually in the spring.
Related: America's most dangerous beaches and ocean water temperature by city.
Use this data
Free to use with a credit
Need your state's numbers, a beach-by-beach list or a quote? Email Laurence Tuchin, Founder: laurence@surfspotguide.com.
Suggested citation
SurfSpotGuide (2026). America's Dirtiest Beaches (2026). https://www.surfspotguide.com/surf-statistics/dirtiest-beaches
Download the full data (CSV)