Not trying to ignore your point, I am aware gmina might try and force their own solutions without respect to the more general law (there's been cases resolved in favor of the common people in the past). If you have any more details why you absolutely have to connect to the municipal sewage system please let me know.
https://sip.lex.pl/akty-prawne/dzu-dziennik-ustaw/utrzymanie...
Not trying to ignore your point, I am aware gmina might try and force their own solutions without respect to the more general law (there's been cases resolved in favor of the common people in the past). If you have any more details why you absolutely have to connect to the municipal sewage system please let me know.