If you start from Tongxiang, drive to Gao Qiao now, then take the No.9 line to Xieqiao Town, Haining, go straight to Shanghai-Hangzhou double track, turn right to Hangzhou, and drive about 1 km. Generally speaking, people from other places go to Yan Guan to watch the tide, and the eight treasures and old salt warehouses in Haining are also good. I don't know exactly how to get there, but you can ask the locals after you enter Haining.
The tide on the 3rd will arrive around one o'clock in the afternoon, but it is usually not very punctual. You'd better arrive early, of course, the sooner the better.