Analysis &
Recommendations
2014
Natural Gas Distribution
Facilities Report
Supplemental Report
Released December 2015
To download the report or to access additional analysis, visit www.cga-dirt.com.
This report may be referenced as the DIRT Annual Report for 2014. © 2007, 2008,2009,2010, 2011, 2012, 2013 all rights reserved.
Table of Contents
Executive Summary ........................................................................................................................ 1
Introduction ..................................................................................................................................... 2
Damages Submitted by Reporting Stakeholder .............................................................................. 3
Right of Way Where Damage Occurred ......................................................................................... 4
Underground Damage Prevention Analysis.................................................................................... 4
Site Marking Characteristics by Locator ...................................................................................... 11
Analysis of Natural Gas Facility Damages by Census Division................................................... 12
Enforcement Authority Analysis .................................................................................................. 16
Data Quality Index (DQI) ............................................................................................................. 17
COMMON GROUND ALLIANCE - 2014 DIRT
Natural Gas Distribution
Executive Summary
The Common Ground Alliance (CGA), in cooperation with the American Gas Association (AGA), has
conducted a separate analysis of the damage reports submitted to its Damage Information Reporting Tool
(DIRT) affecting natural gas distribution facilities in 2014. Data from the entire DIRT dataset, selected
from reports in which Natural Gas was the Affected Facility Operation, and Distribution and Service
Drop was the Type of Facility Affected, were extracted and analyzed. These are equivalent to distribution
mains and service lines in as much as those terms are commonly used by in the gas industry. The analysis
examined only records where damage occurred, i.e., near misses were filtered out. The analysis provides
the gas industry a targeted picture of the factors that contribute to damages to its facilities, which in turn
enables more targeted actions to reduce these damages. It also provides relevant comparisons of damages
affecting natural gas facilities versus all other facilities.
Some of the key findings of the analysis are as follows:

Compared to all other facilities, natural gas had higher percentages of damages caused by Notification
NOT Made and Locating Practices Not Sufficient.

The most common rights-of-way where natural gas facility damages occur are public city streets and
private landowner property. However, damages on private property are twice as likely to not have
been preceded by a one call notification.

The leading types of excavator affecting natural gas facilities are contractor/developer and
occupant/farmer (in both cases the first listed represents the vast majority). However, damages
involving occupant/farmer are three times as likely to have a root cause of Notification NOT Made.

Contractor/Developers doing landscaping and fencing work have significantly higher rates of
damages caused by Notification NOT Made.

There is good statistical correlation between Call Before You Dig awareness and percentages of
damages caused by Notification NOT Made, which suggests that damages attributed to Notification
NOT Made could be expected to decrease as Call Before You Dig Awareness increases.

Natural gas facility operators in states with enforcement by a public utility commission have lower
rates of damages per one call ticket than states with other (or no) enforcement.

The concentration of damages caused by Notification NOT Made on private landowner property, and
by occupants, is likely due to several factors, such as exemptions for certain types of excavators (e.g.,
homeowners) and excavation activities (e.g., hand tools), variations in 811 awareness, education and
outreach, and enforcement.

Better categorization of the Insufficient Excavation Practices could lead to more targeted corrective
actions to reduce these types of damages, whether it be improved excavator training, regulations, best
practices, etc. Since Excavation Practices Not Sufficient is the leading root cause group, reducing
these damages would go a long way toward bring down damages overall.
COMMON GROUND ALLIANCE - 2014 DIRT
Natural Gas Distribution
1
Introduction
This report provides a summary and analysis of the damages submitted to DIRT that occurred during the
year 2014 affecting natural gas distribution facilities. For 2014, 77,192 of the 266,2141 damages reported
to DIRT involved natural gas distribution and service/drop as the affected facilities. Of the 77,192 natural
gas damages, 26,081 involved distribution facilities (i.e., distribution mains) and 51,111 involved service
drop facilities (i.e., service lines). For purposes of this report, these two components together are referred
to as natural gas facilities. Where relevant, this report points out differences in the DIRT data between
natural gas facilities and other facilities. The report also incorporates data that the U.S. DOT Pipeline and
Hazardous Materials Safety Administration (PHMSA) collects from natural gas distribution facility
operators.
Participants contributing to this report included representatives from Common Ground Alliance (CGA),
FMI Corporation (CGA’s consultants that prepare the annual DIRT North America report), the CGA Data
Reporting and Evaluation Committee annual report task team representing natural gas distribution
operators, and the American Gas Association.
Exhibit 1: Percentage of state/province DIRT-reports involving natural gas facilities and total DIRTreported natural gas facility damages
The North America DIRT report for 2014 analyzed 273,599 “EVENTS” that are defined as “the occurrence of
downtime, damages, and near misses.” This report covers only “damages.” “Near misses” (the question “was there
damage to a facility?” is answered “No”) are filtered out of the populations of records applicable to natural gas
facilities and to all other facilities.
1
COMMON GROUND ALLIANCE - 2014 DIRT
Natural Gas Distribution
2
Damages Submitted by Reporting Stakeholder
As shown in Exhibit 2, natural gas operators and locators were the leading reporting stakeholders.
Compared to 2013, reports from locators increased by 12% while reports from natural gas operators
decreased by 14%.
Exhibit 2: Natural gas facility damages submitted by reporting stakeholder
2014
46,801
2013
50,000
40,237
45,000
35,000
24,646
Events
30,000
25,000
27,823
40,000
20,000
142
384
33
86
2,567
2,294
18
32
696
744
14
14
3,815
4
28
2,387
1,302
6
16
-
186
5,000
130
10,000
2,741
15,000
Reporting Stakeholder Group
COMMON GROUND ALLIANCE - 2014 DIRT
Natural Gas Distribution
3
Right-of-Way (ROW) Where Damage Occurred
Exhibit 3 breaks down the different ROW types and shows whether the one call center was notified. For
instance, public city streets and dedicated public utility easements had similar percentages of damages not
preceded by a locate request (25.7% and 25.4% respectively). In contrast, the private landowner category
registered 55.6% damages not preceded by a locate request. This difference is likely due to several
factors, such as exemptions for certain types of excavators (e.g., homeowners) and excavation activities
(e.g., hand tools), variations in 811 awareness, education and outreach, and enforcement.
Exhibit 3: ROW in which the damage occurred (excludes Data not Collected/Unknown Other) and
whether it was preceded by a locate request.
Underground Damage Prevention Analysis
During any excavation project, there are three major opportunities to minimize the likelihood of damage
to underground facilities.
1) Requesting that the underground facilities be located in the area to be excavated, typically by
contacting 811
2) Correctly marking the underground facilities (i.e., fulfilling the locate request)
3) Employing proper excavation techniques given the site characteristics and conditions (e.g.,
maintaining clearance, maintaining marks, supporting exposed facilities, using hand tools
when appropriate)
COMMON GROUND ALLIANCE - 2014 DIRT
Natural Gas Distribution
4
The DIRT damage root cause groups2 reflect these three major points of opportunity. The analysis of
additional data elements provides insight into the more common attributes associated with each damage
root cause group. This enables stakeholders to more effectively direct efforts and resources and to reduce
the likelihood of future excavation damages to underground facilities.
Exhibit 4: Distribution of known root cause groups for natural gas facilities, all other DIRT damages,
and total DIRT damages
Excavation Practices Not Sufficient—46% —was the leading root cause group (see Exhibit 4) from
records with a known3 root cause. The leading second level root cause under in this group was Other
Excavation Practices Not Sufficient at 65.9% (see Exhibit 5). Unfortunately, this does not provide much
insight into what was not sufficient about the excavation practices. According to the following excerpt
from DIRT Users Guide, it is intended to by a catch-all when none of the other available second level
choices apply.
All “groups” used in this report are consistent with the groupings used in Appendix 1 of the 2014 DIRT
North America report, except that sewer and water are separated rather than grouped in Exhibits 9 and 10.
2
For purposes of this report, “known” means that records with Unknown/Other and Data Not Collected have been
filtered out of the analysis. This is why, for example, the pie chart for Natural Gas Damages in Exhibit 4 represents
70,094 damages rather than 77,129.
3
COMMON GROUND ALLIANCE - 2014 DIRT
Natural Gas Distribution
5
Excavation practices not sufficient: The excavator did not use proper care or follow the
correct procedures when excavating near a facility. Choose one of the following 2nd-level
causes:
o
o
o
o
o
o
o
Excavation practices not sufficient (other): None of the 2nd-level causes described below
applies.
Failure to maintain clearance with powered equipment - as defined by applicable state
regulations or underground facility owner.
Failure to maintain the marks: The marks deteriorated or were lost and the excavator
failed to request that they be restored/refreshed. If the state law has a ‘life-of-ticket’ that
has been exceeded, consider selecting No notification made to the one call center.
Failure to support exposed facilities: Facility failed due to lack of support in accordance
with generally accepted engineering practices or instructions provided by the facility
operator.
Failure to use hand tools where required.
Failure to verify location by test hole (pot holing): Some state regulations define a
’tolerance zone‘ around buried facilities and require that the accuracy of the facility
marks be verified by exposing the facility by hand digging prior to excavation within the
tolerance zone, or require hand digging or special precautions when working within the
tolerance zone.
Improper backfilling. Damage caused by improper materials (ex: large/sharp rocks) in the
backfill or improper compaction of the backfill.
The damage reports involving gas facilities had Other Excavation Practices Not Sufficient less often (65%
vs. 91.8%) than reports for all other DIRT damages,4 but there is still room for improvement.
DIRT’s File Upload Specification for enter data by batch entry (typically an Excel Spreadsheet – which is
how most data is submitted to DIRT), Excavation practices not sufficient (other) corresponds to
INSUFEX. Better categorization of the insufficient excavation practices could lead to more targeted
corrective actions to reduce these types of damages, whether it be improved excavator training,
regulations, best practices, etc. Since Excavation Practices Not Sufficient is the leading root cause group,
reducing these damages would go a long way toward bring down damages overall.
For purposes of this report, “all other DIRT damages” refers to damages reported to DIRT in 2014 to facilities
other than natural gas distribution or service/drop facilities. In descending order of number of DIRT reports, these
are Telecommunications, Cable TV, Electric, Water, Liquid Pipe, Sewer, and Steam.
4
COMMON GROUND ALLIANCE - 2014 DIRT
Natural Gas Distribution
6
Exhibit 5: Distribution of known root causes for group Excavation Practices Not Sufficient
The second and third highest root causes cited for damages involving natural gas facilities were
Clearance Not Maintained (14.9%) and Hand Tools Not Used Where Required (11.4%) (See Exhibit 6).
These root causes were in the same ranked order for all other DIRT damages as natural gas damages,
Clearance Not Maintained at 5.3% and Hand Tools Not Used Where Required at 1.5%.
Exhibit 6: Distribution of known root causes for group Excavation Practices Not Sufficient
COMMON GROUND ALLIANCE - 2014 DIRT
Natural Gas Distribution
7
The second largest known root cause for excavation damages to natural gas facilities was Notification
NOT Made, with 28%. Exhibit 7 categorizes this versus other known root causes by excavator group.
While the total number of damages was comparatively low for occupant/farmer (4,871 occupant and 36
farmer), this group did not provide one call notification in 68% of the reported damages. Furthermore,
41.3% of that 68%involved hand tools. By contrast, for the contractor/developer group, Notification NOT
Made was the root cause for 22% of the damages, of which 25% involved hand tools. The factors
discussed previously relating to right-of-way; exemptions, awareness, education, and enforcement also
likely contribute to the differences seen here.
Exhibit 7: Notification NOT Made vs. All Other Known Root Causes by excavator group
Exhibit 8 details the damages for the Excavation Practices Not Sufficient root cause by excavator and
equipment type for natural gas facilities. Contractor/developers using backhoe/trencher equipment
recorded the highest number of damages in 2014 (19,779). The second largest excavation-equipment
category for contractor/developers was Unknown, indicating that there is room for improvement in
collecting details. In contrast, the occupant/farmer group recorded only 1,456 (1,054 occupant and 24
farmer) damages involving backhoe/trencher equipment, but 2,650 (2,597 occupant and 7 farmer)
damages involving hand tools. Twenty-three percent of Occupant damages involved distribution facilities
(gas mains) and 77% involved service/drop facilities (service lines). Understandably, occupants more
often have small projects confined to their own property and often work with hand tools or small powered
excavation equipment. Again, factors such as exemptions, awareness, and enforcement come into play.
COMMON GROUND ALLIANCE - 2014 DIRT
Natural Gas Distribution
8
20,000
18,000
16,000
14,000
12,000
10,000
8,000
6,000
4,000
2,000
-
DNC/Unknown
Other
Hand tools
Drilling
Backhoe/Trencher
Excavation Equipment
Damages
Exhibit 8: Excavation Practices Not Sufficient root cause by excavator and excavation equipment type
Excavator
Exhibit 9 again looks at damages attributed to Excavation Practices Not Sufficient and excavator group,
but now looks at the work performed. Excavation for energy/telecom work recorded the most damages at
4,431 for the contractor/developer group. Fencing and landscaping/irrigation/agriculture projects were
involved in the fewest damages. Projects for sewer, water, and street/roadway work, as well as Data Not
Collected (DNC/Unknown), each recorded around 3,000+ damages.
5,000
4,500
4,000
3,500
3,000
2,500
2,000
1,500
1,000
500
-
DNC/Unknown
Street/Roadway
Water
Sewer (Sanitary/Storm)
Landscaping/Irrigation/Agriculture
Fencing
Energy/Telecom
Construction/Development
Work Type
Damages
Exhibit 9: Segmentation of Excavation Practices Not Sufficient root cause group by excavator type and
work performed
Excavator
COMMON GROUND ALLIANCE - 2014 DIRT
Natural Gas Distribution
9
Exhibit 10 looks at damages to natural gas facilities from the contractor/developer excavator group. It
firsts examines the type of work performed by this group and shows that 24% of the damages occurred
while performing energy/telecom work. A fairly equal distribution can then be seen for sewer, water,
construction/development, and street/roadway work. These work types are then examined further to see
the distribution of the various damage root causes. Landscaping, fencing, and construction/development
have the greater percentages of damages attributed to Notification NOT Made than the other types of work
performed.
Exhibit 10: Examination of natural gas facility damages attributed to contractor/developer and the
distribution between work performed and damage root cause
Facilities affected known events
Distribution or Service/Drop
Other Facilities
99%
1%
Excavator type
Contractor/Developer
Other
74%
26%
Work
performed
Damage root cause
Energy/Telecom
24%
Sewer
17%
Water
17%
Construction/Development
16%
Street/Road
Landscaping*
Fencing
54%
51%
4%
14%
58%
38%
3%
26%
42%
34%
2%
27%
56%
15%
6%
29%
2%
1%
16%
15%
4%
11%
37%
17%
11%
12%
3%
4%
3%
5%
18%
48%
4%
5%
41%
5%
*Includes agriculture
COMMON GROUND ALLIANCE - 2014 DIRT
4%
Natural Gas Distribution
10
Site Marking Characteristics by Locator
Exhibits 11 (natural gas facility damages) 12 (all other DIRT damages) compare site marking
characteristics for damages involving locates performed by contractor and utility locators These exhibits
indicate that contract locators perform the majority of locates, but to a lesser degree for natural gas facility
operators, i.e., 76% versus 98% for all other DIRT damages. In both exhibits the contract locators
perform better in terms of marks being visible and accurate at the time of the damage.
Exhibit 11: Site marking characteristics by locator (known) for natural gas facility damages
Locator
Locate marks visible?
Locate marks correct?
Yes
90%
No
16%
Contract
Locator
76%
Yes
84%
10%
Yes
22%
No
No
78%
All locate requests made
Yes
24%
Yes
74%
75%
26%
No
Utility
Locator
25%
Yes
23%
No
No
77%
Exhibit 12: Site marking characteristics by locator (known) for all other DIRT damages
Locator
Locate marks visible?
Yes
Contract
Locator
Locate marks correct?
12%
94%
6%
98%
Yes
88%
No
17%
No
83%
Yes
No
All locate requests made
Yes
2%
Utility
Locator
29%
65%
No
35%
No
COMMON GROUND ALLIANCE - 2014 DIRT
Yes
71%
10%
90%
Natural Gas Distribution
Yes
No
11
The data underlying Exhibits 11 and 12 indicate there may be some confusion and inconsistencies in how
these questions are interpreted and answered. For example, if marks are not visible, it is unclear how it is
determined if they are accurate. The following excerpt from the DIRT Users Guide explains how these
questions are intended to be used.
Were facility locate marks visible in the area of the excavation?
Facility locate (see definition in Glossary) marks are the marks that result from a valid one call ticket,
with correct information, and in accordance with state law. Select one of the following from the dropdown menu.


No – The worksite was not marked at all, or the work site had been marked, but the marks were
deteriorated or were missing.
Yes – Choose if the owner of the damaged facility responded by marking their facilities. Choose
if marks were generally visible from a valid locate, even if part of the facilities were missed, such
as service, main extension, offset, etc.
Analysis of Natural Gas Facility Damages by Census Division
Exhibit 13 depicts the number of natural gas facility damages by region, comparing each with the data
from the previous year. In all but three regions, West North Central, Mountain, and Pacific, the number of
damages went down from 2013 to 2014. The East North Central region recorded the highest number of
damages at 19,289 for 2014, followed by the West South Central (12,731) and South Atlantic (12,018).
Exhibit 13: Natural gas facility damages by Census Division
COMMON GROUND ALLIANCE - 2014 DIRT
Natural Gas Distribution
12
Also shown is the percentage of U.S miles of natural gas main within each region, based on data from
U.S. DOT Pipeline and Hazardous Materials Safety Administration (PHMSA). Although Canada is
included in the share of damages but not miles of main, it is evident that the shares of gas main and
damages in the U.S. regions do roughly correspond. When both metrics are ranked high-to-low the
highest two (East North Central and West South Central) and bottom two (New England and East South
Central) match, with some shuffling of the regions in the middle. An analysis was conducted on these two
variables that resulted in a correlation coefficient5 (R-square) of 0.70. This suggested that the variability
in natural gas damages can be explained by variability in miles of main.
Exhibit 14 shows a direct correlation of Call Before You Dig awareness to the amount of natural gas
damages attributed to Notification NOT Made. For natural gas damages, approximately 36% of the
variability in Notification NOT Made as a percentage of a region’s damage root cause can be explained by
the division’s Call Before You Dig awareness (R2 = 0.3615). While this is not as high as would be
preferred in a laboratory setting, it is relatively high in a real-world scenario, which is more accepting of a
lower correlation coefficient. This analysis suggests that in the case of natural gas damages, Call Before
You Dig awareness has a direct relationship to the variability of damages attributed to Notification NOT
Made. This suggests that one can expect the number of damages attributed to Notification NOT Made will
decrease as Call Before You Dig Awareness increases.
Exhibit 14: Correlation of natural gas damages to Call before You Dig awareness
5
See http://www.businessdictionary.com/definition/coefficient-of-correlation-r.html for a definition of correlation
coefficient.
COMMON GROUND ALLIANCE - 2014 DIRT
Natural Gas Distribution
13
When we looked at the distribution of known root causes in Exhibit 4, the overall picture showed that
Excavation Practices Not Sufficient was the root cause for 46% of all natural gas facility damages.
Notification NOT Made followed at 28%, and Locating Practices Not Sufficient came in at 20%. When
we look at the same data by Census division (see Exhibit 15), the picture becomes more variable. For
example, Canada and the Pacific Region have higher incidences of Notification NOT Made, while the
East South Central, New England, and West North Central regions have higher incidences of Excavation
Practices Not Sufficient.
Exhibit 15: Distribution of known root cause groups by Census Division
Exhibits 16, 17, and 18, which examine damages to natural gas facilities by excavator type, equipment
type and work performed, also indicate variability by region.
Exhibit 16: Distribution of known excavator type by Census Division
COMMON GROUND ALLIANCE - 2014 DIRT
Natural Gas Distribution
14
Exhibit 17: Distribution of known excavation equipment-type damages by Census Division
Exhibit 18: Distribution of known work performed by Census Division
COMMON GROUND ALLIANCE - 2014 DIRT
Natural Gas Distribution
15
Enforcement Authority Analysis
To align this year’s natural gas report with the 2014 DIRT North America report, we also examined the
effect of enforcement on the damage rate of each state. However, instead of using DIRT and OCSI data,
we used publicly available information from the PHMSA on excavation damages and locate requests.
Exhibit 19 utilizes this PHMSA data to calculate the damages per 1,000 locate requests for the natural gas
distribution operators in each state and categorizes the states by their enforcement authority. States with a
Public Utility Commission or Other6 have a lower damage rate than states with no enforcement authority
or for which the Attorney General or Law Enforcement serves as the enforcement authority. The same
was found when a similar analysis was conducted for the 2014 DIRT North America report.
Exhibit 19: Damages per 1,000 excavation tickets for varying enforcement authority per PHMSA
reported data
6
Other is comprised of damage prevention authority and one call advisory board.
COMMON GROUND ALLIANCE - 2014 DIRT
Natural Gas Distribution
16
Data Quality Index (DQI)
The Data Quality Index (DQI) measures the completeness of damage data submitted to DIRT. Data that is
complete (i.e., information is provided for all fields) receives a score of 100%. For reported natural gas
damages in 2014, the natural gas and locator reporting stakeholders submitted the largest number of
damages and both had DQIs of 76%. Public works scored the highest DQI at 82%, but only submitted
744 damages. Exhibit 20 compares DQI across natural gas damages for the various reporting
stakeholders, but it also compares the DQI for natural gas damages and all other DIRT damages. It is
apparent that records involving damages to natural gas facilities have a significantly higher average DQI
compared to all other DIRT damages, 75% DQI versus 63% DQI, demonstrating that more complete data
is submitted for natural-gas-related damages.
Exhibit 20: Comparison of DQI by Reporting Stakeholder between natural gas facility damages and
damages to all other facilities.
2014 Natural Gas DQI
2014 All other DQI
100.0%
90.0%
40,000
80%
35,000
76%
83%
70%
79%
77%
78%
75%
77%
76%
80.0%
76%
70.0%
71%
74%
30,000
25,000
76%
82%
69%
66%
60.0%
63%
61%
60%
50%
50.0%
51%
20,000
44%
41%
15,000
40.0%
43%
30.0%
30%
10,000
20.0%
5,000
0
DQI
Natural Gas Damages
2014
45,000
10.0%
40,237
27,823
2,741
2,567
2,387
744
384
130
86
32
28
16
14
0.0%
Reporting Stakeholder Group
COMMON GROUND ALLIANCE - 2014 DIRT
Natural Gas Distribution
17
Exhibit 21 examines DQI rates by Census Division for natural gas facility damages and all other DIRT
damages. Slicing the data by Census division reveals large differences in some regions (e.g., Mountain,
Middle Atlantic) between the quality of reports involving natural gas facilities and those involving all
other facilities.
Exhibit 21: Comparison of DQI by Census Division between natural gas facility damages and damages to
all other facilities
2014 Natural Gas DQI
2014 All other DQI
25,000
100%
90%
20,000
77%
77%
76%
79%
80%
70%
55%
63%
61%
70%
71%
70%
70%
15,000
79%
74%
70%
68%
77%
DQI
Natural Gas Damages
2014
56%
60%
50%
50%
46%
10,000
45%
40%
30%
5,000
20%
10%
0
19,289
12,731
East North West South
Central
Central
12,018
8,016
7,941
5,335
4,848
3,751
2,997
266
South
Atlantic
West North
Central
Pacific
Mountain
Middle
Atlantic
Canada
East South
Central
New
England
0%
Census Division
COMMON GROUND ALLIANCE - 2014 DIRT
Natural Gas Distribution
18
2014 DIRT Data Analysis
& Recommendations
Natural Gas Distribution Facilities Report
Prepared by:
FMI Corporation
CGA’s Data Reporting & Evaluation Committee
This report summarizes the analysis of all natural gas distribution facility events
submitted into DIRT for 2014. To view the complete DIRT Report for 2014,
visit www.cga-dirt.com