The City of Memphis owns and operates an extensive wastewater management infrastructure system with over 3,600 miles of wastewater collection pipeline. The City has, for well over a decade, implemented various components of a sewer collection operation and management system designed to reduce the number of sanitary sewer overflows (SSOs) in the system.
In September, 2012, the City of Memphis executed a Consent Decree in the United States District Court for the Western District of Tennessee for the rehabilitation of the Wastewater Collection and Transportation System (WCTS) in the metropolitan area. The rehabilitation is to be accomplished during the next 10 years.
To manage the work, the City of Memphis retained the services of a Program Manager which is an engineering firm specializing in this type work. The Memphis Program Manager consists of a team of firms, each with special skills needed to effectively manage the project. The project has an with an estimated value of $250 million over the 10-year program span.
Allen & Hoshall is one of the partner firms of the Program Manager team, designated as Memphis Sewer Assessment & Rehabilitation Program (SARP10) . To date, the team has retained the services of Sewer System Evaluation System (SSES) contractors to perform investigation services in specific areas of the Memphis system. These contractors are firms that have invested heavily in not only expensive electronic equipment but also in personnel and training to perform this work in cities throughout the nation. The investigation services consist of cleaning the interior of existing sanitary sewers, inspecting the interior condition of sewer using specialized closed circuit television (CCTV) equipment, smoke testing of sewers to locate surface leaks, inspection and documentation of manhole defects, and, in some cases, dye water testing and other investigative techniques.
To date, the first section of evaluation work has been completed by two selected contractors. The first section, referred to as the “Pilot Area”, included a portion of the Orange Mound community in the Cane Creek drainage area and a portion of the Hickory Hill area. In this “Pilot Area”, more than 323,000 linear feet of gravity sewers, ranging from 6-inch diameter to 36-inch diameter, have been smoked tested, cleaned, and inspected using CCTV with documentation of defects and problem areas. In addition, more than 1,000 manholes have been cleaned and inspected with defects documented.
The area of the City covered by the “Pilot Area” work is outlined and shaded in green on the map apove.
The second area of evaluation is currently under way. The work is being performed by three selected contractors and the area covered is in the southwest area of the City. The work is estimated to clean and inspect over 880,000 linear feet of gravity sewer and include more than 2,900 manholes.
From the Consent Decree, the “Priority Areas” in the City are outlined in red on the map above.
As part of the SARP10 program, Allen & Hoshall has employees certified in the PACP (Pipeline Assessment Certification Program) and the MACP (Manhole Assessment Certification Program) as sponsored by the National Association of Sewer Service Companies (NASSCO, Inc.). The PACP and MACP Program was developed to standardize nationwide the method of evaluating defects in sewers and manholes.
As part of the team, Allen & Hoshall has participated in the development of the overall scope of the sewer assessment work, worked on the development and approval of standard specifications upon which the assessment contractors perform the work, designed program field work, provided field inspectors to observe and monitor the contractor’s field activities and viewed many hours of CCTV video tapes and classified defects per PACP guidelines.