The roster of technologies available for wastewater force main inspection has grown from 19 tools three years ago to 37 technologies available today. The number and variety of tools grows daily and the capabilities and reliability of each tool constantly tested and improved. The data provided by these tools ranges widely, from low quality data of limited usefulness to data that is reliable and of high quality, suitable for condition assessment. The costs for obtaining this data varies widely also. Each tool is applicable to specific pipe materials, over a range of pipe sizes and under specific conditions of pipe status. With all these different technologies, the wide range of data quality, the range of costs, operating variables and constantly changing capabilities, the selection of the proper tool or set of tools for a force main inspection program can be bewildering. In order to facilitate the selection process, Brown & Caldwell has developed procedures for preparing decision matrixes and work logic protocols for its clients. These decision tools are custom tailored to address the specific needs of the client and to fit the unique properties of their system. Recent case studies of two very different utility systems will be used to illustrate the process. The paper will describe the development of workflow logic diagrams, and technology selection decision tools to meet two different program goals. The paper will begin with a brief summary of force main inspection technologies.
Decision Logic for Selecting Wastewater Force Main Inspection Program Tools
Authors: Henry R. (Kelly) Derr, PE; Brown and Caldwell, Raleigh, NC
2012 North American Society for Trenchless Technology (NASTT) No-Dig Show