In the late evening and early night are when most Taiwanese take showers. At this time you have to be very careful when walking in small lanes around the city. This is because some showers and other drains will end up like this. A hole in the outer wall that drains into the street and through the tiny holes in the street for the water to fall to the sewer below.
This one is pretty innocuous, but not every single one drains out an inch above the ground. Some are much higher, meaning you have to be careful of waterfalls of shower water falling down on you. This is also the drawback of wearing shoes without a thick sole, as sometimes the street is wet from all the drainage, and you have to walk through it.
Then again for the most part it can be avoided. Just don't walk down tiny lanes, and by all means avoid any alleys. And most importantly don't have a dog that you have to take for a walk at night.
