There are Weimeidong (outdoor), Chengdong Gymnasium and Senhai Haoting (outdoor) in the east of the city. The first one is next to the senior high school, the second one is opposite the Tushan Garden (take the 1 1 road), and the third one is in Senhai Haoting, where there is swimming.
Other places include the big beach in Jinghu New District (seemingly).
Other gyms are also good places to practice swimming.
In fact, as long as you look at online group buying, you can not only know where to swim, but also buy group buying tickets, which is cheaper.