on
this link, the institudo estadual do ambiente -
inea, provides the
suitability
of several beaches
in the sepetiba bay area, including
praia do cardo, which is close by to praia da ponta grossa
and can be used to guess water quality there.
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.