Work group will address growing concern and ensure standards are met in the identification of existing problems.


Our mission is to set standards for the assessment, maintenance and rehabilitation of underground infrastructure. In short, to ensure work is done right. In addition to controlling costs and maximizing efficiencies, however, standards are specifically developed to protect our communities from disaster, including those that occur as a result of cross bore.

Cross bore is a term used to describe an instance where an underground utility is installed directly through an existing utility. This is usually a result of horizontal boring or directional drilling techniques in the installation of a new utility conduit, with the install drilled directly through an existing, crossing utility. Natural gas providers commonly use directional drilling as an economical method to install gas distribution piping for mains and service lines.

Gas line cross bores into sewer laterals — which, since they are gravity drainlines, serve as a direct conduit to the home — damage the pipe and block flow, eventually leading to sewer backups. When the homeowner calls for a plumber to clear the line, a diligent plumber will generally try to clear the line with a root cutter, which could cut the gas line, resulting in a catastrophic explosion with significant property damage and, occasionally, loss of life. Often, roots will also camouflage cross bores, therefore the plumber has to be absolutely diligent when using CCTV to verify.

Related: NASSCO Corner: Time to Recertify?

Best practices to identify these potentially dangerous cross bores are continually evolving based on lessons learned. The principle activity behind a good program involves deploying a CCTV camera with a locating transmitter inside the sewer lateral. The most effective and thorough way requires a lateral launch from the mainline, ensuring that 100 percent of all connecting branch lines are located and inspected.

Most states have regulatory statutes and fines that relate to pipeline damage prevention, but such actions typically only apply when the damage is reported. Cross bores in gravity drain systems, such as storm drain and sewer systems, remain undetected until the crossing utility owner conducts maintenance, or the cross bore itself clogs the line. Typically, most cross bores will remain undetected for years.

Gas distribution providers are launching aggressive sewer investigation programs to ensure that all cross bores from past drilling efforts have been corrected. Referred to as legacy programs, time is of the essence to prioritize the areas most likely to have cross bores. Legacy programs are currently viewed as a maintenance operation, with many NASSCO contractor members involved in identifying and reporting these potential disasters. Unless gas companies can implement a fool-proof procedure for preventing cross bores on future installs, the legacy programs will most likely never end, and the responsibilities of contractors to properly inspect these lines will continue to be a critical step in keeping our communities safe.

Related: NASSCO Corner: Taking the Challenge

Many municipalities are deploying the Pipeline Assessment and Certification Program and Lateral Assessment and Certification Program in the inspection of their sewer mains and laterals. In PACP, the OBI code, or “object intruding through a pipe wall,” is used to identify cross bores. Anytime this code is used, it alerts the system owner of the existence of a cross bore, and should be investigated immediately to determine if it is potentially a gas main. Many times the line can be “cleared” if there is no gas service in the vicinity, but it is imperative that this be done quickly and corrective action taken as soon as possible. Such swift and effective action for all segments in which the OBI code is used can prevent significant loss of property, and even save lives.

Understanding the importance of cross-bore assessment, NASSCO has recently formed a work group to address the growing cross-bore concern, and unite NASSCO members and others within our industry to ensure standards are met for identifying existing cross-bore activity and identifying ways to prevent them in the future. If you would like to know more, email info@nassco.org or call 410/442-PIPE (7473).

Get the EDge  Training and Continuing Education Courses

PACP TRAINING

Related: NASSCO Corner: PACP Preview

April 4-6 Northville, Michigan
Includes Manholes and Laterals!
Recertifications Welcome
Trainer: Brandon Conley
Contact Ashley Groves for more information or to register: 248/349-0904 or email pacp@dohenycompanies.com

April 7 Northville, Michigan
One-Day Recertification Course
Trainer: Brandon Conley
Contact Ashley Groves for more information or to register: 248/349-0904 or email pacp@dohenycompanies.com

April 24-26 Marriottsville, Maryland
Includes Manholes and Laterals!
Trainer: Ted DeBoda
Contact Dawn Jaworski for more information or to register: 410/442-7473 or email dawn@nassco.org

Subscribe: If you don't want to bring your iPad into the bathroom, we can send you a magazine subscription for free!

April 25-27 San Francisco, California
Includes Manholes and Laterals!
Recertifications Welcome
Trainer: Brandon Conley
Contact Ashley Groves for more information
or to register: 248/349-0904 or email pacp@dohenycompanies.com

May 2 Marriottsville, Maryland
PACP User Recertification
Trainer: Ted DeBoda
Contact Dawn Jaworski for more information or to register: 410/442-7473 or email dawn@nassco.org

May 9-11 Atlantic City, New Jersey
NJWEA Annual Conference
Includes Manholes and Laterals!
Recertifications Welcome
Trainer: Brandon Conley
Contact Ashley Groves for more information or to register: 248/349-0904 or email pacp@dohenycompanies.com

Subscribe: Save the trees for beavers, sign up for our E-Newsletter!

May 15-17 Marriottsville, Maryland
Includes Manholes and Laterals!
Trainer: Ted DeBoda
Contact Dawn Jaworski for more information or to register: 410/442-7473 or email dawn@nassco.org


Related Stories

Want more stories like this? Sign up for alerts!