Common questions.
- Is Muir beach - south safe to swim today?
- Muir beach - south is currently safe for swimming. Recent samples within safe ranges.
- Does rain affect water quality at Muir beach - 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 Muir beach - south located?
- Muir beach - south is located in the Marin area of the San Francisco Bay region (coordinates: 37.8581°N, 122.5750°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 Muir beach - 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: Open-Meteo — Precipitation (CC-BY 4.0) · Marin County — Beach Water Quality (Esri Standard (as-is)) · Pipeline status