SSO Data By State

California operates the most active SSO reporting program of any state — but almost none of it flows into the federal ECHO database. The State Water Resources Control Board (SWRCB) administers the Statewide General Waste Discharge Requirements (WDR) Order, which requires all publicly owned collection system agencies to report SSOs through the California Integrated Water Quality System (CIWQS). CIWQS data is detailed and publicly accessible but separate from federal infrastructure. California's 2006 statewide WDR was one of the most comprehensive SSO regulatory frameworks enacted by any state, predating the federal eRule by nearly two decades. For California-specific data, go directly to the SWRCB's CIWQS public SSO portal.

Texas has more NPDES-permitted wastewater facilities than any other state — over 2,000 collection systems and treatment plants. The Texas Commission on Environmental Quality (TCEQ) administers the TPDES (Texas Pollutant Discharge Elimination System) program. Texas utilities report spills to TCEQ and the data flows to ECHO, but coverage quality varies significantly across the state's vast geography. Rural utilities and smaller systems in the Rio Grande Valley, where poverty rates are high and infrastructure is aging, are particularly likely to be underrepresented. Texas is also notable for the scale of its storm-related overflow events — Hurricane Harvey (2017) and Winter Storm Uri (2021) each caused hundreds of documented SSOs.

Florida has relatively strong SSO reporting in ECHO, in part because the Florida Department of Environmental Protection (FDEP) has aggressively enforced reporting requirements and because the state's sensitive water bodies — the Everglades watershed, Indian River Lagoon, Tampa Bay, numerous springs — create strong regulatory and political pressure for compliance. Florida also has a large number of small utility systems, many serving coastal municipalities, that discharge to highly sensitive waters where even modest overflows can trigger beach closures and public health advisories. The state's flat topography and high groundwater table create I/I challenges throughout.

Ohio has some of the most complete SSO data in ECHO among Midwest states. Ohio EPA has required electronic reporting through NetDMR for years and has been proactive in following up on SSO compliance. The state also administers significant State Revolving Fund (SRF) loan programs for sewer infrastructure, and receiving those loans typically requires strong reporting compliance. Ohio's largest cities — Columbus, Cleveland, Cincinnati, Akron — have all been under federal consent decrees requiring major sewer system improvements, which generates rigorous documentation of SSO events. The Great Lakes basin context adds federal pressure on water quality compliance.

New York presents a complex picture because the state operates both combined sewer systems (in New York City and dozens of older upstate cities) and separate sanitary sewer systems across the rest of the state. CSO and SSO data are reported through different frameworks, and the NYSDEC has historically been more rigorous about CSO Long-Term Control Plans than SSO-specific tracking. New York City's DEP operates what may be the most extensive CSO infrastructure program in the country, with a comprehensive Green Infrastructure program. SSO events outside NYC — in suburban and rural areas — are covered in ECHO but with varying completeness depending on the size and resources of the utility.

The Gulf South states present some of the most concerning data gaps in the ECHO database. Mississippi's sewer infrastructure, particularly in rural areas and historically underinvested communities of color, is severely degraded — and reporting to the state and federal databases is correspondingly incomplete. The MDEQ has faced chronic underfunding that limits both inspection capacity and enforcement. Louisiana has similar challenges, particularly in the greater New Orleans area and along the Mississippi River industrial corridor. Alabama's ADEM has improved reporting in recent years but rural counties still have significant gaps. Multiple environmental justice organizations have documented the disproportionate burden of inadequate sewer infrastructure in Black and low-income communities across this region. These states likely have among the highest ratios of unreported to reported SSOs in the country.