For a house that I'm in the process of buying, there is what I think is called a "catch basin" in the backyard (under a manhole-looking cover). It seems that the kitchen sink may be draining into this, which results in some food/etc items appearing in there.
A home inspector warned me about this (the catch basin should be for storm drains, but appears to have sanitary sewage in it), but the owners said that a kitchen sink draining to a catch basin is normal in older homes.
Around the internet, I can see some vague off-hand references to kitchen sinks in older houses draining into a catch basin, but I have trouble finding detailed information. Is this indeed common and okay? What is the point of this system, and why would modern homes no longer do this?
The house in question is rather old (built around 1920). It's one of the million bungalows around the Chicago area.