Basement Plumbing question

[michaelodonnell123]

Hello everybody,

In my basement, I have two pipes coming out of the floor with caps on them. (See pic). Recently, it rained heavy here and the town sewer in front of my house got backed up and some water was squirting out from under the cap. I have since called the town to clean the sewer. so that the water flows better and not back into my house.

Are these clean out pipes where you would remove the cap to put in a snake and clear out a clog? If yes, why would somebody glue the cap on (making it hard to remove to clean the clog). How do you remove the cap? There is no nut on top to put a wrench on it. Do they just pop off or do you turn them with some special tool. The cap feels like plastic and it's on tight. I can't remove it with my hand.

Before you say 'call a plumber', they want $400 to just show up. I am just trying to learn more about the plumbing in my basement.