Dealing With Laterals: Abundant Challenges

Part 1 Of An Exclusive 3-Part Series
By Jeff Griffin, Senior Editor | September 2010 Vol. 65 No. 9
A Hoffman Southwest crew installs a lateral.

“The majority of sewer laterals in the Western U.S. are more than 30 years old and are in poor condition,” says Mark Metcalfe, vice president of operations. “Heavy root intrusion, cracked pipes and offset joints are common. When blocked, most of these laterals can be opened with routine cleaning but can be a source of I&I as can roots that travel from the lateral into the main line.”

Laterals receive no maintenance because cities or sanitary districts do not have inspection programs for laterals on the public side and owners of the private side laterals are not aware of laterals until there is a problem.

“Most cities consider the lateral the property owners responsibility from the home or building until it enters the city easement or street mainline,” Metcalfe continues. “Another problem is that most cities do not have a lateral program that requires inspection and repair after a backup or when the property is sold.”

Excavation replacement of laterals is very difficult and expensive, but Metcalfe says his company finds many city building departments are not familiar with trenchless technologies.

“Education about trenchless options would help property owners be aware of alternatives for rehabilitation,” Metcalfe believes.

In fact, trenchless procedures of rehabilitating old sewer laterals by relining and replacing old laterals with new pipe are being used today, but their full potential has not been realized.

Lack of standards
Gil Carroll, director of business development at Applied Felts says from his company’s perspective, the most glaring issue holding back the advancement of lateral rehabilitation with linings is the lack of the same standardization, inspection and quality assurance that has been established for cured-in-place pipe (CIPP) rehabilitation of mainline sewers. Applied Felts is a leading manufacturer of CIPP liners.

“For example,” says Carroll, “we don’t see the industry adhering to the ASTM 1216 in lateral relining. We still see installers using ambient cure, which will never be as effective as heat curing and could create negative impressions of the CIPP process overall on the part of those not familiar with the process. This could result in CIPP being disallowed in areas where improper installation techniques have been followed.

“The lateral market needs to follow suit in order to ensure complete integrity of installations, which is critical to improving the condition of sewer laterals in the U.S.”