on
this link,
the instituto estadual do ambiente (inea)
provides the
suitability of several beaches, including
prainha and
pontal de
sernambetiba, that can be used to determine water conditions
at macumba beach.
constantly updated, the red flags mean that swimming is not
advisable, green flags mean waters are clean, and yellow
flags suggest using own judgment. any of rio's beaches
may have polluted
waters within 24 to 48 hours following heavy rains.