By Wendy Wert
On July 26, 2007 the Los Angeles Basin Section (LABS) of CWEA hosted a training meeting at Sambi of Tokyo Restaurant in Downey. The City of Los Angeles operates and maintains the largest wastewater collection system in the United States.
More than 6,700 miles of sewers connect residences and businesses to the City’s wastewater treatment plants. About 450 million gallons per day flow through this system, which serves over four million people in a 600 square mile service area that includes Los Angeles and 29 contracting cities and agencies. Reknown guest speaker Adel Hagekhalil discussed management issues associated with this complex system.
Adel Hagekhalil, has over 18 years of experience in the area of civil and environmental engineering. Adel currently serves as a division manager with the City of Los Angeles’ Bureau of Sanitation where he is responsible for the overall wastewater facilities advance planning and engineering activities. Under his direction, the City has just completed an award-winning 20-year integrated water resources plan (IRP).
Adel is managing the implementation of the IRP, the City’s collection system settlement agreement and the collection system condition assessment and capital improvement planning efforts. Adel has published numerous technical papers, received many awards, and participated in various conferences and committees. At the meeting, Mr. Hagekhalil shared knowledge through discussion of successful examples such as the City’s collection system management efforts that include a strong commitment to protect the public health and environment, and innovative win-win partnerships. These partnerships include various City offices, regulators, environmental organizations and community groups.
In August 2004, the City of Los Angeles entered a Collection System Settlement Agreement (Settlement Agreement) with the United States Department of Justice and the United States Environmental Protection Agency. The primary intent of the Settlement Agreement is to reduce sanitary sewer overflows (SSOs). Three years after reaching the landmark Settlement Agreement with the USEPA, the LARWQCB and the Santa Monica Baykeeper, the City has achieved watershed progress as shown by a 70 percent reduction in sewer overflows. This was accomplished through a comprehensive sewer improvement program.
Mr. Hagekhalil discussed the elements of then agreement and the City’s program. The rehabilitation and replacement program began with the following four initiatives:
- CCTV Inspection (with priority given to sewer basins with the highest number of SSOs per 100 miles).
- Structural Condition Assessment and Needs Identification
- Project Development and Prioritization
- Project Implementation
The collection system ranges in diameter from 6 inches to 150 inches and consists of primary and secondary sewers which includes approximately 130 miles of abandoned sewers and approximately 70 miles of sewers within City limits and owned by other agencies. The plan is focused on approximately 6,470 miles of City-owned sewers that are currently in service. Of these 6,470 miles, approximately 5,820 miles are secondary sewers (sewers ranging in diameter from 6 inches to 15 inches) that collect flow from building laterals and convey the sewage to the primary sewer system. In addition, approximately 650 miles of primary sewers (sewers greater than 15 inches in diameter) convey sewage from the secondary sewers to treatment facilities.
The City’s spill reduction program consists of four main components: An aggressive maintenance program to manage SSOs caused by factors that can be influenced by periodic maintenance, an aggressive Fats, Oils, and Grease (FOG) Control Program to minimize the introduction of FOG into the collection system; A comprehensive capacity assurance program to identify and correct capacity deficiencies in the collection system, and an aggressive capital improvement program to identify and remove collection system defects that can cause SSOs and that cannot be managed effectively using a periodic maintenance program.
Mr. Hagekhalil presented specific system performance results, over the past six years these programs have proven to be highly effective and have achieved a 70 percent reduction in the annual number of sewer overflows from Fiscal Year 2000 to Fiscal Year 2005.
The three ships of a successful program:
These proven strategies are paralleled in the Sewer System Management Plan (SSMP) now required by the State WDR. Adel credits the success of the program with consensus building that relies on teamwork across a broad spectrum of individuals with varied skills and backgrounds but united in purpose, the desire to reduce SSO’s. When asked how to achieve such consensus, Adel offered this advice “Don’t hesitate to share the credit, fully engage your constituency, it’s a win-win partnership and that is how you build trust.”