Responding to Emergency Excavations & Repair

First and foremost: Know what emergency scenario you are responding to and the potential hazards on the excavation and repair site.

During the course of any given day, line locating technicians respond to a variety of emergency 811 excavation notifications. Many of these emergency excavation requests involve a service outage, broken poles, gas leaks, water leaks and sewer backups. Many of these emergencies can create hazards to public and property which need emergency excavation to take place in order to repair and make safe.

During my years as a full time utility locator, I gained a lot of personal experience
responding to hundreds of these emergency excavations involving repair of our aging infrastructure. Here are a few tips for line locators and any other responders to these types of emergencies.

First and foremost: Know what emergency scenario you are responding to and the potential hazards on the excavation and repair site.

Responding to Damaged or Leaking Natural Gas Lines
These were the emergencies that worried me the most. I once heard a horror story about a vehicle pulling up to a gas leak. The  engine ignited a blast and killed the driver. I knew that I never wanted to be the person who brought the ignition source to the fuel source. With natural gas or other hazardous material lines, it is important to determine wind direction and park upstream.  Remember that natural gas is lighter than air and can collect in covered spaces and mix with air at just the right level to make it very explosive. If a buried pipe is leaking or the pipe was struck during directional drilling operations, the gas can migrate through the soil into nearby basements or the sewer pipes that lead to houses or buildings where the gas may find an ignition source. Do not park over valve lids or manhole covers.

The valve you accidentally park on may be needed to shut off the flow of gas from the leaking pipe. Manhole covers are often removed to vent out natural gas that may have seeped into the sewer or other conduit systems.

If the fire or police department is onsite, contact the incident command and let them know who you are and why you are there. Do not enter the controlled site until you obtain permission and are informed the area is now safe for you to proceed. Line locating equipment is not intrinsically safe. Electrical arcs could occur when applying or adjusting the direct connection leads.

Responding to Emergencies involving Broken Power Poles and Downed Power Lines
These emergencies are often associated with storm damage or a car accident. During a heavy ice storm, I received an emergency call out around 1:30 in the morning. The emergency call was made by a power company crew who needed to replace a broken pole that was hit by a car. The broken pole was located in front of a bank. I had a power line and telephone cable down and had to spot them before the pole could be replaced.

I have always had respect for electricity and I was determined not to touch anything metal onsite. Since the pole had already been broken, and ice continued to build on the power lines, the crew supported the pole with their bucket truck. I decided to get away from that hazardous area and apply my locate signal on the cables from the bank and trace the lines back to the pole. I chose to apply my locate signal indirect to each line because I didn’t want to directly connect my signal transmitter to the meter or transformer or shield of the phone cable just in case a short had occurred when the pole was broken, which may have made the grounding systems of both the electric and telephone systems electrified. As I traced the lines back to the broken pole, I kept my eyes open and approached from the opposite direction the pole was leaning. I do remember thinking that my hard hat was probably not going to do much good if the pole came down on my head but it’s all I had.

In this scenario, do not park near broken poles or downed power lines, or any other overhead lines in the general area. The pole was
installed to support the weight of the lines and now the lines are supporting the pole. This is sure to put a lot of extra stress on the entire overhead system in the area that could break additional poles and lines in the area well after the initial damage.

Responding to Emergency Locates involving Damaged Water Lines
Water leaks are very common on both small and large scale occurrences. There is a difference between a trickle leak and a full-on ruptured pipe. Some water pipe ruptures are powerful enough to wash out the soil beneath the grass and roadways and could result in an unexpected sinkhole onsite. Anything on the roadway, including the people and equipment, could end up in the bottom of the hole if they’re not extra careful.

When responding to emergency excavation notifications for repair and restoration of both pipeline and utility outages and leaks it is good to be paranoid. In some cases you may be heading into harm’s way. Take your time in evaluating the site and making a plan of approach.


Bob Nighswonger is president of Utility Training Academy, Inc., specialists in damage prevention training programs for accurate line locating and excavation safety. Learn more at utasearch.com.

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