A note of caution: I grew up in an urban area with city sewers. Our house
had a drain in the basement floor. My dad had a headstone nearby. I
remember a helluva storm where all the power went out and the streets were
flooding. Dad put a big stack of newspapers over the drain and set the
headstone on top. We ended up getting a litle water near the drain but we
had neighbors who had water all the way up to the basement ceiling.
I remember dad saying later that he had been very concerned that the
pressure on the pipe between the drain and the sewer could burst because of
the increased pressure. BTW, the house was probably built in 1925-1930.
All this verbage just to give you something to consider.