Underground Cable Installation Broke Water Line and Now it's Leaking

I can't recall when but Xfinity had came over and buried our cables underground. During the process they had asked us if it's okay to turn the water off because they needed to -- at the time we didn't realize they had actually broken our waterline in the process of digging our cables which is why they wanted to turn the water off.

Fast forward to today, we noticed a high water bill and were told there's a leak in our line. After getting a plumber over to do some digging, they found the leak at the junction box where the Xfinity cable was dug. It looks like they had broken our waterline and attempted to fix it, but instead of using proper polyethylene pipe (like the one they had broke), they used a wiring conduit or something which is not meant for water. This was not good enough and thus eventually leaked which lead us to this problem. 

Who do I need to contact in regards to getting reimbursed for this?