A practical algorithm for 3-D interpretation of images taken in a sewer by a robot-inspector is presented. Modern sewers made of concrete present regular circular structures originating at the pipe ends as well as at the joints of the pipe sections. These pipe ends and joints provide regular marks on the sewer images and can be used for their 3-D interpretation. The key idea of the paper is to ...

Methane formation and emission in sewer systems has not received as much attention as hydrogen sulphide formation. Through field measurements from two rising mains, with an average sewage temperature of 28.4 and 26.6 degrees C, respectively, at the time of sampling, this study shows that a significant amount of methane can be produced in sewer systems, and that this production is positively cor...

DESCRIPTION As the infrastructure in the United States ages, increasing importance is being placed on rehabilitating the nation's wastewater treatment collection systems. Cracks, settling, tree root intrusion, and other disturbances that develop over time deteriorate pipe lines and other conveyance structures that comprise wastewater collection systems. These deteriorating conditions can increa...