Ypao Beach, Tumon Bay is a saltwater beach in Guam County, Guam. Across 502 bacteria samples collected between 2021 and 2026 at nearby monitoring stations, it earns a Beach Safety Grade of B — Good.
About 3% of samples at Ypao Beach, Tumon Bay exceeded the EPA Beach Action Value of 104 CFU/100 mL for Enterococcus — the threshold at which water managers typically post a swimming advisory. In practice that means the safe-swimming limit was rarely crossed here over the monitored period. Bacteria samples rarely exceed the safe-swimming threshold.
In the most recent full reporting year, Ypao Beach, Tumon Bay was under a swimming advisory for about 13% of its monitored beach days — a useful gauge of how often problems recur here beyond any single sample.