What kind of question is that? Storm sewers are dangerous places for many reasons and should never be entered, except by workers with special training.
Sewers can contain invisible poisonous gases, dangerous wildlife, sharp objects, and slippery surfaces. They can also flood during even small rain storms. So never go in a manhole.
Sewers are not safe places. They can contain poisonous gases, dangerous wildlife, sharp objects, and slippery surfaces. They can also flood.
Photo: Chicago Public Library