The Causes of Underground Utility Damages in North Carolina in 2020

Third-party damages to the subsurface infrastructure seem to be a persistent issue that negatively
influences the integrity of underground utilities and its vital services to citizens of North Carolina.
North Carolina 811 (NC 811) has been conducting research studies to identify causes and remedies
of third-party damages. The studies solicited stakeholders’ (i.e., excavators, locators, and utility
owners) perceptions about the topic. Clearly, there are several factors contributing to third-party
damages which reinforces the industry understanding that preventing damages is a shared responsibility.
Overall, the direct causes of third-party damages could be grouped into four categories:

Excavators’ insufficient practices (EIP) include damages resulting from no locate requests, invalid
use of a locate request (e.g., wrong area was excavated), and failure to use hand tools to uncover
subsurface utilities. In North Carolina, the following direct causes fall under this category:
– No notification made to the One Call center/811
– Excavator dug prior to valid start date/time
– Excavator failed to maintain clearance after verifying marks
– Excavator dug prior to verifying marks by test hole (pothole)
– Excavator provided incorrect notification information
– Excavator failed to protect/shore/support utilities
– Excavator dug outside area described on ticket

Locators’ insufficient practices (LIP) include inaccurate marks and the absence of marks. In
North Carolina, the following direct causes fall under this category:
– Unmarked or inaccurately marked due to locator error
– Incomplete locates

Utility owners’ insufficient practices (UOIP) include the following:
– Inaccurate utility record/maps
– No response from operator/contract locator
– Unlocatable facilities

General industry practices may be a result of common industry practice or work conditions.
In North Carolina, the following direct causes fall under this category:
– Abandoned facilities:
Abandoned facilities do not belong to any utility owners/operators; they contribute to less
accurate marks and more damages. They are not a result of a particular stakeholder practice.
Rather, they are a result of a general industry lack of sustainable processes to keep
records of abandoned facilities. Thus, this challenge should be addressed by a national
effort to better manage these facilities.
– Temporary nature of marks:
The temporary nature of marks was ranked second in the causes of damages as suggested
by excavators (Al-Bayati and Panzer 2019). Marks can be faded or lost due to weather and
work conditions, and marks are removed as soon the excavation starts.
– Previous damage
– Deteriorated facility
– Tracer wire issue:
Utility owners/operators often apply tracer wire to plastic facilities to help locate them.
Damages to tracer wire could be perceived as low-risk damages by excavators (Al-Bayati
and Panzer 2019). Largely, low-risk damages (e.g., telecommunication and television
damages) have lower potential monetary impact on construction project schedules and
budgets, unless they involve fiber-optic telecommunication lines. Therefore, low-risk damages
are often not reported. Broken tracers contribute significantly to inaccurate locates.

These insufficient practices not only cause damages but also compromise the entire One Call system,
as has been discussed in a recently published article by Mr. Panzer and Dr. Al-Bayati, entitled
“Reducing Damages to Underground Utilities: Importance of Stakeholders’ Behaviors.” It must be
noted that this cause categorization differs from the CGA’s categorization in two ways:

1) The DIRT report’s cause categories include excavation practices, invalid use of request by
excavator, locating practices, miscellaneous, no locate request, and unknown/other. As previously
discussed, the NC 811’s categorization classifies no locate requests and invalid use of request
by excavator under excavators’ practices. Furthermore, the NC 811 categorization utilizes
utility owner practice and general industry practice categories. Finally, the NC 811 categorization
only handles known data and totally ignores the unknown other category. For more information
about the NC 811 categorization, see Al- Bayati and Panzer’s book Underground Utilities
for Construction Practitioners and Homeowners or other published reviewed articles by Al-
Bayati and Panzer.

2) The NC 811 research team considers these causes direct causes, whereas CGA’s DIRT Report
considers them root causes. According to Al-Bayati et al. (2021), direct causes consist of
unsafe acts (e.g., digging prior to a valid start date) and unsafe conditions (e.g., failing to protect/
shore/support utilities), whereas root causes, which lead to direct causes, consist of human factors
and workplace factors, such as inadequate training and lack of knowledge or skill.

Most of the damages were reported by locators 20,952 (66.0%) followed by excavators 7,214
(22.7%) and utility operators/owners such as natural gas and telecommunications 3,600 (11.3%).
However, almost all excavators have indicated that the cause is not reported (i.e., unknown/other).
The direct cause has been reported in only 16,937 (53.3%) reports, mostly by locators. The
proportions of each case category are presented in Figure 1 based on the known inputs.

Figure 1

The data indicates that excavators’ practices contribute to 68.96% of underground damages
in North Carolina. To better understand the nature of the insufficient practices of
locators and excavators, the actions of each category have been determined (see Table 1).

Table 1

Within the excavators’ insufficient practices, failing to place a locate request through
NC 811 contributed to 6,296 (53.9%) of the damages. The next two contributing factors
are: (1) not verifying marks by test-holes 2,561 (21.9%), and (2) failing to maintain
clearance 772 (6.6%). According to North Carolina damage prevention law, excavators
must not use mechanized equipment until visually verifying the location of marked utilities
[87-122 (C) (9) (a)]. Excavating prior to verifying the marks seems to be a widespread
issue that represents the second cause of damages due to excavators’ insufficient practices. In
addition, maintaining clearance between a facility and the point of any mechanized equipment
is required to reasonably avoid damages [87-122 (C) (9) (C) and (10)]. Failing to maintain the
needed clearance was the third contributed factor to the damages in North Carolina. Thus, NC 811
education efforts should focus on these issues. Finally, digging prior to start data or after the
ticket expiration represents the third and fourth causes within excavators’ practices. It is
anticipated that marks will be in place when digging within these circumstances.

Finally, abandoned facilities represent 85% of the general industry practices category. Damage
prevention training programs must address this issue carefully. However, the challenge remains
that abandoned facilities are not present in the maps provided to the locators and therefore the
locator does not have knowledge of the presence of these abandoned lines.

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