Establishing Conveyance Capacity with Multiple Concurrent Planned Projects

The City of Los Angeles (City) owns and operates one of the largest wastewater collection systems in the country. It is made up of over 6,700 miles of public sewers that serves over four (4) million residents and 29 contract agencies. As the City continues to grow and develop the Bureau of Sanitation (BOS) regularly review, comment on future Capacity Availability as well as provide sewer capacity connection permit for concurrent projects ranging from new developments, redevelopments of existing facilities and construction dewatering. In order to ensure that the sewer system can safely convey permitted and anticipated discharges, a GIS based predictive tool was developed for Capacity Availability evaluation. This tool relies on databases that store information such as record of all proposed developments, approved discharges, hydraulic gauging data, and closed-circuit television (CCTV) data. A GIS mapping interface illustrates the developments and is used to trace flows downstream of a connection point with all permitted and anticipated discharges highlighted. With the available information an Environmental Engineer is able to visualize sewer inputs and take into account previous development project discharges to assess hydraulic conveyance availability.