The New Age for Sewer Planning at the City of Los Angeles

The City of Los Angeles Department of Public Works Bureau of Sanitation (LASAN) is responsible for operating and maintaining one of the world’s largest wastewater collection and treatment systems. It has been conducting advance planning for its 6,700-mile sewer system for decades using very conservative and technically sound engineering principles and tools. The sewer assets are rapidly deteriorating and so it is paramount for LASAN to continually upgrade the sewer system to ensure that the health of the public and the environment are protected.In 2007, LASAN custom-developed an application called SPOT (Sewer Planning Optimization Tool) to fit the specific planning needs of LASAN. SPOT was successfully used to prepare the 100 highest priority secondary sewer basin plans required by a Collection System Settlement Agreement (CSSA). The SPOT model played an important role in secondary collection system (i.e., sewers less than 16 inches in diameter) planning and rehabilitation by efficiently tracking and addressing structural and hydraulic deficiencies, conducting studies to evaluate the effectiveness of various root control methods, and providing support for Difficult-To-Access Reaches (DAR) program. This customized solution seemed to be a great fit but it posed to be a large challenge when the contract with the SPOT developer expired resulting in a program that would quickly be obsolete.LASAN needed to continue their progress with their sewer planning and they identified a need to obtain a Commercial-Off-the-Shelf (COTS) software that provides as a minimum, the same basic functionalities as SPOT, and is supported by a commercial vendor who can provide maintenance and upgrade at a nominal cost. LASAN selected Innovyze’s InfoMaster tool to fill that role.By utilizing CCTV inspection data, GIS data layers, GIS-integrated hydraulic models, O&M data, and other available data sources within Innovyze’s InfoMaster tool, LASAN is continually and systematically able to continue where SPOT left off and obtain a more complete estimation of the true likelihood and consequence of sewer asset failures. With this information, they are able to continue to provide defensible prioritization schedules on their most critical sewer assets.This paper concentrates on how LASAN is using off-the-shelf GIS-integrated applications that integrate with their existing workflows to develop a comprehensive capital planning tool. Techniques, tips, and requirements for these types of analyses will be presented along with a working example demonstrating how LASAN performed a detailed Risk Assessment and develop a complete Rehabilitation Plan for the LASAN wastewater system.