Ninety days of readings.
Log scale · MPN/100mLEach dot is one sample taken by the monitoring agency. The dashed brick line marks the EPA single-sample limit.
SafeCautionUnsafe
Common questions.
- Is Pomponio State Beach (Peninsula, South) safe to swim today?
- Pomponio State Beach (Peninsula, South) is currently inconclusive for swimming. Last sample is over 30 days old — too stale to be a reliable swim-safety indicator.
- When was Pomponio State Beach (Peninsula, South) last tested?
- The most recent water-quality sample at Pomponio State Beach (Peninsula, South) was collected on Jul 6, 2026 (32 days ago). California monitoring agencies test Bay Area beaches weekly during swim season (roughly May through October).
- What is the bacteria level at Pomponio State Beach (Peninsula, South)?
- The latest reading at Pomponio State Beach (Peninsula, South) shows E. coli at 288 MPN/100mL (EPA single-sample limit: 235).
- Does rain affect water quality at Pomponio State Beach (Peninsula, South)?
- Yes. Heavy rainfall washes bacteria and pollutants from land into the water, raising contamination risk for 24–72 hours. The past 48 hours recorded 0.00 in of rain; the past 72 hours recorded 0.00 in. Our advisory threshold is ≥1.00 in over 48h (or ≥0.50 in over 72h) for enclosed or storm-drain beaches.
- Where is Pomponio State Beach (Peninsula, South) located?
- Pomponio State Beach (Peninsula, South) is located in the Peninsula area of the San Francisco Bay region (coordinates: 37.2980°N, 122.4060°W). You can get turn-by-turn directions via Google Maps or Apple Maps directly from this page.
- How is the water quality data for Pomponio State Beach (Peninsula, South) collected?
- Bacteria samples are collected by California state and county health agencies under the AB 411 Safe-to-Swim program and reported to the state's Safe-to-Swim database (data.ca.gov). Rainfall figures come from Open-Meteo forecast and archive data. Bay Area Swim aggregates both sources and updates every morning.
Also nearby
Data: California Safe-to-Swim (ODbL 1.0) · Open-Meteo — Precipitation (CC-BY 4.0) · Pipeline status