on
this link, the institudo estadual do
ambiente (inea)
provides the
suitability of
several beaches on
ilha do governador, including
praia da bica
/ jardim guanabara, which is close to
praia do alentejo and can be used to guess water quality.
constantly updated, a red
flag means that swimming is not advisable, a green flag
means waters are clean, and a yellow flag suggests using own
judgment.
any of rio's beaches may
have polluted waters within 24 to 48 hours following heavy rains - while cleaning is underway, many of ilha do governador's beaches are normally not suitable for swimming.