The tug Liz Vinik was back at the North River water treatment plant with the sludge barge Maria alongside on Wednesday. Maria was loading residual solids (sludge) for dewatering at the Passaic Valley water treatment plant on Newark Bay. The North River plant is most often serviced by the city’s own fleet of tankers but we have seen this privately owned barge calling here periodically over the past year, perhaps because two of the city’s tankers are currently out of service. The photos were taken from Riverbank State Park, which sits above the sewage facility.