"Mikepier" wrote in message
...
6 family 3 story brick house in Brooklyn, NY. Built around 1925. I
recently discovered the downspout was clogged. It goes into a 4" ( or
5"?) cast iron pipe into the ground in the backyard. Lots of junk
inside ( leaves, rubber handballs). I could not manage to clear it,
might get a pro to do it.
But just out of curiousity, do these downspouts tie into the bldgs
sewer system? Reason I ask because in the basement there is a cleanout
plug in the floor by the cellar door, with a pipe going out towards
the backyard. Could they have built it that way back then, or did they
run a seperate pipe in the basement floor just for the rainwater? I
did try to run water in the downspout to see if any water was flowing
through the cleanout, but the pipe is 100% clogged.
I'm not sure if there is a drywell back there either.

In all the sewered parts of NYC (and despite our Borough President, Brooklyn
is still part of NYC) all roof drainage must go to the City sewer, not into
your back yard. That 4" cast iron pipe should go to through a trap into
your lateral connection through your house to the City combined sewer. If
the trap has collected debris, it needs to be cleaned out. From what you
say, your lateral is below the cellar floor so there is not an easy cleanout
for the trap. I'd hire a sewer cleaning service.
--
Peace,
BobJ