Employees of K&R Plumbing of Clackamas install a new sewer line along an alley between 4th and 5th avenues last week. The project is part of the third phase of inflow and infiltration improvements of the city sanitary sewer system, according to Public Works Director Mike Adams. Other areas where excavation is planned include sections of 10th Avenue, Oak Terrace between 9th and 10th avenues and Westwood Lane, he said. The company is trying to…