Take pictures of the damage with a non-digital camera. Get pictures of the place where the damage was caused. And get a lawyer, you may not need one but it is nice to have. And contact your insurance agency and explain to them what happened. Cause getting the city to pay for anything is going to be a drawn out process that the city can afford to procrastinate on but you cant. Its best to let your insurance company sue them for the money and let the insurance deal with the rest.