Arcipello said:btw how do you access the DLC? i see the sewer entrances dotted about but can never enter them
That's probably the exit to the sewers. There should be one somewhere very near to each one you can't go through, which is the entrance.
There's one right by the ramp leading out of the area where your Arc was, with the guy who helped you at the start standing there by a stall to point it out for you.