@article {Derr:2009:1938-6478:436,
	author = "Derr, Henry R. and Hubbard, Phillip",
	title = "Evaluation of Acoustic Technologies for the Inspections of Wastewater Force Mains",
	journal = "Proceedings of the Water Environment Federation",
	volume = "2009",
	number = "2",
	year = "2009",
	abstract = "The need to inspect wastewater force mains has become more acute as utilities expand and refine their asset condition assessment programs. These efforts have been complicated by the fact that force mains were seldom designed with redundancy or access for internal inspection. As a result, most force mains can not be easily taken out of service for inspection.<P></P>The Hampton Roads Sanitation District (HRSD) in Virginia is faced with these plus a number of additional challenges. HRSD operates over 430 miles of pressure mains in a complex interconnected system which conveys flow from over 700 pumping stations most of which are owned and operated by satellite systems and not controlled directly by HRSD. To inspect this complex system, HRSD needed technologies which do not require the force mains to be taken out of service and which would provide usable and dependable data.<P></P>After reviewing the technologies available for pressure pipe inspection, two acoustic sensing systems were selected for further testing and evaluation. A pilot program was conducted to evaluate the applicability of these two acoustic technologies for wastewater force main inspection.<P></P>This paper provides a brief summary of the inspection technologies available for pressure mains, and describes acoustic technologies in more detail. The scope and goals of the HRSD pilot program will be defined and the results of the pilot testing discussed. The emphasis of the paper will be on a discussion of the results of the field testing and the lessons learned during the program. The goal of the paper is to suggest adaptations to improve reliability and durability of the acoustic technology for use in wastewater pressure mains.",
	pages = "436-449",
	url = "http://www.ingentaconnect.com/content/wef/wefproc/2009/00002009/00000002/art00030",
	doi = "doi:10.2175/193864709793846934",
	keyword = "Acoustic, inspection, condition assessment, pressure mains, wastewater"
}