School of PE Blog

I have always enjoyed the month of April since it marks the first full month of spring. The days become longer, warmer, and there is generally a feeling of optimism in the air. Folks are coming out of their winter hibernation and looking forward to more outdoorsy activities. April also marks National Safe Digging Month since the month also marks the beginning of peak construction season. Contractors, crews, and inspectors are out in full force with their equipment, installing new buildings, pipelines, and other infrastructure. National Safe Digging Month is both a celebration of the construction industry and a reminder of the importance of industry safety.

In 2008, the Common Ground Alliance (CGA) started National Safe Digging Month as a safety awareness initiative in response to the increased digging activity in the Springtime, and it is recognized today by the United States Congress and State Governors. Established in 2000, CGA is a non-profit organization committed to the damage prevention of underground infrastructure and protecting individuals in the North American utility industry. Membership consists of both companies and individuals striving towards these goals. CGA is managed by a board of directors and is always looking for stakeholders such as regulators, excavators, locators, engineers, and emergency workers, among others, to support damage prevention efforts. In 2005, 811 was designated as the national One Call number for anyone completing digging projects in America. And it has been noted that a utility line is damaged approximately every six (6) minutes.

The Pipeline and Hazardous Materials Safety Administration (PHMSA) is an agency under the United States Department of Transportation (USDOT) and embraces National Safe Digging Month; in this calendar year (2022), PHMSA will be awarding grants to support damage prevention programs at the state level. They have also partnered with other pipeline stakeholders in this effort. When dialing 811 through the utility One Call system, you must first wait three (3) days for utilities in the site-specific area to respond. The three (3) days are a grace period for utilities to respond and locate their infrastructure accordingly (it is a violation for the excavator to start too soon; you must allow ample time for utilities to provide a response). Some utilities will complete their markings with their associated colors, while others may provide drawing plans for the site-specific area. It is also acceptable to respond with no facilities in the area (if the area is clear of that utility infrastructure). However, it is unacceptable to not respond through the One Call System, and this will be recorded as a response. It is important to note that failing to respond to a One Call request is a violation and can lead to ramifications for the negligent utility (remember, the utility One Call responses are recorded, so this would appear as written documentation if legal proceedings were to occur).

Historically, there has not been much regulation in the utility industry; unfortunately, many lines are mismarked or not marked at all (this is why underground utility damage continues to occur despite improved safety measures). I work in the utility industry, so I have reviewed old main and service records that are oftentimes missing information. Incomplete As-Builts can lead to hit lines that can cause unplanned shutdowns, costs to repair infrastructure (fiber optic is very expensive!), and both human and property damage, so these drawings and sketches must be rectified immediately-not just for recordkeeping but also to ensure safety. As a utility worker, I also frequently see safety updates about topics such as trenches, equipment handling, and personal protective equipment (PPE).

There have been communication miscues in the past too. I had a project where records indicated the utility line was only four (4) feet deep. However, it turned out to be 14 feet deep! A resurfacing project had been completed earlier but was not communicated to the other utilities, so the records were never updated properly. You could imagine my surprise when I received the shoring invoices-it was quite the fee! This is also a reminder that shoring and trench boxes are required when trenches exceed five (5) feet deep. This is an Occupational Safety and Health Administration (OSHA) standard that is designed to prevent trench collapses that can cause an unprecedented grave for workers. OSHA has issued citations before and even noted fatalities since contractors and companies did not adhere to this standard. Always remember that while some requirements may appear strict and arduous, they are designed to protect workers and increase the probability of a smooth operation.

You must always call 811 before digging, regardless of how small or how shallow a project may be (some diggers have mistakenly believed that certain projects do not require the 811 locates, since their project occurs at a shallow depth). It is true that most underground infrastructure is installed at least a few feet deep, but this is not guaranteed; you must absolutely notify your state 811 center about your construction intentions. I had a project that involved a gas service line installation for a new warehouse. There were concerns about the depth of the existing gas main since vibrations and tremors from heavy-duty trucks and tractor trailers could potentially dislodge the service tee and cause a gas leak. So, remember to dial 811 before digging! The utility One Call system also serves as a reminder for businesses, homeowners, and contractors to have utilities marked before digging and to be wary of underground lines in the area.

Utility locates for each state in the United States utilizes (like the pun?) the 811 System for Subsurface Utility Engineering (SUE). Some states have unique 811 names such as Sunshine 811 (Florida), OKIE 811 (Oklahoma), Blue Stakes of Utah 811 (Utah), and Gopher State One Call (Minnesota). The utility One Call system covers public right-of-way (ROW) areas. Utilities may use the public ROW space in municipalities to install their infrastructure (mains, poles, etc.) since utilities are designed to serve the public after all. Each utility receives a different color representation: gas is yellow, electric is red, water is blue, sewer is green, telecommunications is orange, and reclaimed water/slurry is purple. Construction sites are marked with white paint.

Utility lines are installed with tracer wire, so the line path is detectable. The tracer wire is typically copper wire since copper is a metallic conductor. Locating instruments are used to identify the utility lines like a metal detector. Marker balls can also be used to identify specific objects such as valves and other pipe fittings; these can be critical since valves can restrict flow and fittings such as elbows can change pipe direction. Locators should be aware of these items and their approximate locations so they can properly notify the excavator if there are potential concerns of key infrastructure conflicting with new pipeline installation. Caution warning tape is the last line of defense before contacting the utility line when digging underground. Both marker balls and caution tape can also follow the same utility color scheme to help the excavator identify the respective utility. Some utilities may have the same pipe material used at a jobsite, so you might not always be able to differentiate one utility from another.

I have also attended different OSHA training courses, and OSHA offers some interesting information on their website about recorded violations and fatalities. Statistics indicate that roadway incidents and falls (including falls into trenches) are leading causes of work-related fatalities. Trench collapses also contribute towards workplace violations and citations. There has been recent discussion about heat hazard prevention initiatives as temperatures will start increasing over the next few months. Spring and summer months offer longer and warmer days, so there is greater risk of heat and sun exposure.

Digging is dynamic since it involves construction, PPE, utilities, and regulatory requirements. National Safe Digging Month is not a brand-new concept, but it is certainly worthwhile to review and reinforce good digging practices. OSHA has noted recurring themes with incidents such as falls and trench collapses, so there is always opportunity for improvement in the construction industry. You can help protect human life, reduce costs, and improve utility recordkeeping and infrastructure. So, while you're enjoying the weather this spring, remember to know what's below-call before you dig! And of course, keep checking back with School of PE for more blog posts!

Many different types of engineers will oversee projects that require digging and utility line detection. If you are interested in becoming a professional engineer, School of PE provides comprehensive FE and PE exam review courses to help you on your journey to licensure! Register for a course today.