I've noticed the raw sewage smell since they redid the road back in 08, particularly the grates at the corner of Lewis and Front.

This is an ongoing issue, every time that it rains or it's too hot smells like that, it goes back to years of complains. The truck with the giant hoses it's to clean the sewage system that it's too small for all the waste from lewis and front street (both sides). People met with public works about it but nothing was done as usual. Sounds like a big job has to be done to fix the problem.

I remember hearing about a street flooding that caused sewage to backup into a front st resident's basement. wonder if there are pipes crossed that is causing sewage from houses to flow into the street drainage.

Yes, that was during storm Sandy last year, the sewage system overflowed, the water from the river was all the way to the other side on front street (on the lewis and front street intersection the water was about a feet deep) I think that the sewage system meets in that intersection with no place to go sometimes, On a heavy rainy day you can see how one at a time the sewers start to overflow so the water and everything else goes to the streets and then back down when the rains stops. The smell is from everyhting else that does run like water and stays on the street and sidewalk.

Engineering Department assigned this issue to Catch Basin Cleaning Division -Department of Engineering

There are overflows from the sanitary sewers into the Quinnipiac at 255 Front Street and 279 Front Street. During periods of heavy rainfall the sanitary sewers cannot cope with the heavier flows, and a mixture of rainwater and sewage discharges into the river. This is the most likely cause of the sewage smells, as there are usually two or three complaints per year in the vicinity. There is a long term control plan in place to provide separate storm and sanitary sewer systems throughout the city. The catch basins have been checked, and they are clean.

i learned that the reason the sewer grates smell like raw sewage is because there is sewage in them. There's only one sewer pipe running under the street which is rainwater + household sewer mixed. The whole pipe does not flow into the quinnipiac river but goes directly to the treatment plant. So when they overflow in heavy rainfall, avoid the puddle!