How are we doing?
Beach and coastal health ratings show mixed results. Beaches are sensitive to pollution and erosion due to sea level rise and the San Diego region contends with managing their effects. Sewage from the Tijuana River remains a dominant cause of closures for South County beaches. In 2025, there were 1,404 closures in 2025 (measured in beach mile days) caused by pollution from the Tijuana River, which is fewer than the 2,087 closures in 2024, but these numbers are high compared to past years. Beach closures unrelated to the sewage from the Tijuana River were minimal, but the number of advisories rose sharply from 392 to 742, raising concerns about other sources of pollution. As a coastal region, protecting residents and beaches from pollution, rising sea levels, and flooding remains essential to maintaining the region’s quality of life.
Rating: Mixed Rating
Fewer beach closures, but pollution is still a serious problem
Beach closures and advisories
What Are Beach Mile Days?
Beach Mile Days (BMD) are calculated by multiplying the distance of the beach posted or closed by the number of days of the posting or closure. This ensures that a closure to a small section of beach is weighted differently in the overall total to a closure of a large section of beach.
In 2025, pollution from the Tijuana River caused 1,404 beach mile days of closures, which is 683 beach mile days fewer than 2024. Beach closures related to the Tijuana River pollution have significantly decreased since 2023, but remain high. Beach closures unrelated to the Tijuana River increased between 2024 and 2025 by 89% or 350 beach mile days, highlighting concern for beach water quality across the region’s coast.
A public health survey by the CDC found that 59% of residents in the South Bay and Tijuana River Valley area reported heightened stress due to the ongoing pollution and unpleasant odors in their community. The level of stress among residents was comparable to that seen following Category 5 hurricanes and the Flint water crisis.
In 2025, San Diego County recorded 8.5 inches of rainfall and 42 rain advisory days, both below the ten-year averages of 9.7 inches and 48 rain advisory days. Stormwater serves as both a potential water supply and a source of pollution. The San Diego County Department of Environmental Health issues rain advisories in response to rainfall events of more than 0.2 inches of rain, as urban runoff sparked by higher levels of rainfall can carry bacteria into the ocean. As a result, the number of rain advisories and the total rainfall in a year have generally tracked together.
In a region impacted by drought, rain often provides a welcome reprieve and reduces wildfire risk. However, recent years have seen a shift toward more intense rainfall, with heavy downpours delivering large volumes of water in short periods rather than across multiple storms. These concentrated rainfall events increase flood risks that can overwhelm San Diego’s infrastructure.
Sea level rise
Since 1973, sea levels in the San Diego Bay have risen nearly 7 inches, posing a significant threat to the region, which relies on its beaches and bayfront as vital environmental and economic resources. This rising sea level is intensifying coastal flooding, already evident during high tides and storm surges. The increasing frequency of storms and floods accelerates beach erosion and brings tons of sewage and urban runoff into coastal areas.
For instance, coastal erosion concerns have resulted in the suspension of the Amtrak Pacific Surfliner service between Oceanside and Irvine. Landslides and other coastal erosion concerns continue to affect the train tracks connecting San Diego County and Orange County. Across the state, California beaches are shrinking. The U.S. Geological Survey estimates that the state will lose 75% of its beaches by 2100.
Beach advisories and closures across the coast
Over a hundred points along the San Diego County coastline are sampled for bacterial levels in the ocean waters. Based on these levels, advisories and closures are issued. The above map groups the advisories and closures of an area within San Diego County that occurred in 2025. Darker orange and purple colors indicate a higher number of advisories and closures, as seen in the south county beaches. These twelve miles of beaches, from Border Field State Park through Coronado, are now regularly closed due to untreated effluent flowing across the border from a collapsing sewage treatment system in Tijuana and on the border.
Coordinating coastal resilience
This deep dive on SDRCC and their coastal resilience projects was developed by Marius van Dongen (‘24)
Our San Diego coastlines depend on our regional leaders and communities. The San Diego Regional Climate Collaborative (SDRCC) is a network connecting public agencies, communities, and jurisdictions to “advance climate change solutions and adapt to climate change.” In a recent Storymap, SDRCC shared an analysis of shareholder perceptions in order to help align definitions of coastal resiliency in hopes of facilitating reinforced collaborative action. Without a shared understanding of coastal liabilities, the cost of inaction is multiplied across jurisdictions. The San Diego Regional Climate Collaborative aims to bring together these communities so that responses to coastal shocks can be strengthened and our region made more resilient.
Moreover, SDRCC emphasizes an approach that ensures that the voices of those most impacted by climate change are at the helm of solution-building. A-bel Gong, Climate Research Manager of SDRCC explained that as heatwaves become more frequent, the importance of beaches are spotlighted: “The beach is an important natural cooling center,” they said in a recent interview. Beaches serve as key refuges, helping to protect those at risk during San Diego’s hottest days. SDRCC’s Storymap provides an “alignment around shared goals,” and creates a new definition of coastal resilience – one that prioritizes the community and their roles as key stakeholders of our beaches. Regional response to the climate crisis will ultimately define the future of our beaches and, in turn, the health of our communities.
Related Indicators
- Outdoor Access
- Climate Change and Planning
- Water
The health of our beaches and the resilience of our coast is key in creating proper outdoor access for everyone.
Why is beach and coastal health important?
High quality of life means the region boasts a thriving economy, a healthy environment, and is an equitable place for all San Diegans to grow and prosper.
Economy
Marine and coastal areas deeply affect San Diego’s economy. In the 2024 fiscal year, San Diego welcomed 32 million visitors who spent $14.6 billion during their stay. This tourism rebound from the 2020 pandemic highlights the enduring charm of San Diego’s beaches, food culture, arts and recreation. Protecting the health and beauty of beaches preserves their economic value and strengthens the economic resilience in times of crisis. Coastal states in America had beach visitations that exceeded previous records during the pandemic.
Protecting marine biodiversity is also an essential strategy for maintaining quality of life in our region. Marine life faces threats by pollutants such as pathogens, chemicals, plastic, and other solid waste, which all have a direct economic impact on coastal cities. Research from the National Caucus of Environmental Legislators found that globally, plastic pollution in the ocean causes a loss of 1-5% of marine ecosystem services, or an economic loss of $500 billion to $2.5 trillion per year. The City of San Diego’s marinas, recreational amenities, and natural assets averaged an annual revenue of $45.3 million between 2013 and 2019.
Environment
Coastal areas serve a unique niche as the intersection of land and sea, requiring dynamic monitoring strategies to maintain environmental health. For instance, San Diego holds 11 watershed systems which all drain into the Pacific Ocean. Stormwater runoff from these watersheds contain urban pollutants like motor oil, pesticides, pet waste, fertilizers, and more, which harm the fragile coastal ecosystems, wildlife, and beach goers. Maintaining the health and quality of our beaches and coastline not only protect the fragile ecosystems but also the people living in and around these areas.
Equity
Not all San Diego communities have the same access to the coast due to limitations such as transportation access, safety, and pollution levels. Visiting beaches can be a low-cost way to avoid the heat during extreme heat events which will increase by 20% to 50% by 2100. Investing in safe access to the outdoors offers the opportunity to nurture resilient residents with a strong sense of stewardship in the face of collective challenges like climate change, environmental degradation, and economic hardship.
Regional Response
Policies
The Marine Life Protection Act of 1999 mandated the reexamination of marine protected areas in California to protect natural habitats. San Diego is home to 11 marine protected areas.
The City of San Diego’s Coastal Resilience Master Plan, adopted in September 2025, identifies nature-based solutions for improving the resilience of the six coastal locations.
30x30 California is a state initiative dedicated to conserving 30% of California’s lands and coastal waters by 2030 through collaborative action to restore biodiversity and improve access to nature. By 2025, 26% of land and 22% of coastal waters was conserved.
The State of California Sea Level Rise Guidance: 2024 Science and Policy Update is designed to meet the diverse needs related to sea level rise decision-making and planning across California.
Projects
In 2022, San Diego County was the first coastal California county to adopt a DNA-based rapid detection method for recreational beaches in San Diego County. This method provides more immediately available information for beach goers to make informed decisions about entering the water.
Re:Beach Oceanside is an ongoing design competition for Oceanside’s coastal resilience development. This project will improve Oceanside’s sand retention and increase beach size and recreational capabilities. The construction is set for 2026 or 2027.
Partnerships
The Binational Resilience Initiative focuses on strengthening collaboration across the border to address shared challenges such as coastal resilience and pollution. The combined efforts of involved nonprofits and foundations has resulted in support for 24 coastal resilience projects.
In 2023, San Diego Coastkeeper, Surfrider, YMCA Surf Camp and a number of other organizations joined hands to form the Border Pollution Coalition.
The San Diego MPA (Marine Protected Area) Collaborative is a network of 30 organizations in San Diego County dedicated to issues surrounding marine protected areas.
One Coastal Community is a bi-national collaborative dedicated to protecting coastlines and the 137,770 individuals living near them.
Watch Video
Watch the Voice of San Diego's San Diego 101 video on how the Tijuana River Sewage crisis affects the region's beaches and coastline
What are we tracking?
We track the yearly trend in beach closures and advisories by Beach Mile Days (BMD = number of days x length in miles of beach under advisory or closed). We also track closures that are specifically due to sewage from the Tijuana River. On this page we also track rainfall and rain advisories. We also map out select beach advisories and closures along the San Diego coast and into Tijuana. Learn more about the data.