“the often forgotten underground world”
DESCRIPTION
“THE OFTEN FORGOTTEN UNDERGROUND WORLD”. UNMARKED SEWER THREATS. AGA Distribution Construction Maintenance Committee Mike Kemper, NPL Construction Company September 16, 2008. Core Business : The safe installation & maintenance of reliable energy distribution systems Over 500 crews - PowerPoint PPT PresentationTRANSCRIPT
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“THE OFTEN FORGOTTEN UNDERGROUND WORLD”
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UNMARKED SEWER THREATS
AGA Distribution Construction Maintenance CommitteeMike Kemper, NPL Construction Company
September 16, 2008
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WHO IS NPL?
Core Business: • The safe installation & maintenance of
reliable energy distribution systems
• Over 500 crews• Over 2500 employees • Operate in 20 states • One of the largest users of
One-Call Centers in U.S
Safety. Quality. Best Cost.
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4.36 4.31 4.09 3.96 4.55 5.46 5.73 5.83 5.28 5.54 5.82 6.69 6.96
5.45 5.56 5.62 5.466.05
6.056.96 6.86
6.307.25
8.349.17 9.45
0
2
4
6
8
10
12
14
16
18
1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007
Milli
ons New
Replaced
NEW AND REPLACEMENT FOOTAGE
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CUSTOMER BASE
•UNS
•CNP
•SWG
•NI
•SWG
•SWG •KGS•KGS
•BGE
•SWG
•XEL
•Nicor
•WGL
•ATO
•DEA
•SWG
•AGL
•SWG
•APS
SRP
ATO•EAS
•ONG
• MERC
• CPS
•BKH
SOCAL
Peoples
•DUK
• GMG
•STRNVP
•NI
•ATO
Safety. Quality. Best Cost.
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WHAT IS TRENCHLESS TECH?
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HOW ABOUT THESE?
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DO WE HAVE A PROBLEM?
Sewer Main
Who’s responsible for marking?
Property line
Cit
y st
reet
House
Lateral to mains
connection
What could happen?
Installed line
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Old Gas Service Line
New Gas Main
Sewer Lateral
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SOME HITS ARE A TIME BOMB!
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MADILL, OK 1/2/2007
OK Natural Gas line was installed in 1992
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Headline:March 13, 2006
Woman, Granddaughters Barely Escape Explosion
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MIDDLETOWN, OHIO 3/16/2006
• After seeing bubbles in the water and smelling the natural gas, the plumber told a grandmother and her three grandchildren to get out of the home immediately.
• March 18, 2006
Middletown Journal
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HOW OFTEN DOES IT HAPPEN?
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ODDS OF GETTING A HOLE-IN-ONE
1 in 12,000
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MINNESOTA
• 27 cross bores reported to the Minnesota Public Utilities Commission
in a 6 month time period.
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PALO ALTO, CA
• 4 blocks inspected
• 24 cross bores found
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ANOTHER PROJECT• 11,000 sewer laterals inspected
• 250 cross bores identified
• 2% were cross bores
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• Just over 400 gas cross bores discovered over 200 miles of sewer main lines – One cross bore located at a school
• Averaged 2 cross bores per mile
• The utility mailed notices to over 50,000 residences asking them to first call a special phone number if they had a sewer backup.
ANOTHER CITY
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AND ANOTHER CITY• Averaged 3 cross
bores per mile of sewer main
• One cross bore located at a hospital
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CGA CONFERENCEMARCH, 2008
• “How many of you have experienced Crossbores?”
• 2/3 of attendees raised their hands
• CGA’s Locating Sewer Service Laterals Committee reached a stalemate and closed the initiative. The team, however, believes this is an important issue and does not want to be satisfied with the status quo. Best Practices Task Group re-formed this fall.
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“The Use of Trenchless Excavation Equipment in Relation to the
Marking of Underground Facilities”
2008
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DOES THERE NEED TO BE BETTER ENFORCEMENT OF VIOLATORS?
Need for better enforcement of violators
100%
0%
Yes
No
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ARE OWNERS/OPERATORS YOU WORK FOR REQUIRED TO MARK THEIR FACILITIES?
Requirement of owners to mark UG utilities - Gas to building wall / meter
87%
13%
Yes
No
Requirement of owners to mark UG utilities - Communication to building wall
85%
15%
Yes
No
Requirement of owners to mark UG utilities - Electrical to building wall / meter
80%
20%
Yes
No
Requirement of owners to mark UG utilities - Sewer to building wall
13%
87%
Yes
No
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LEGISLATION STATUS
• Most states already require some level of locating by the sewer owner/operator
• States need to enforce sewer locating laws
• In the meantime …
Safety. Quality. Best Cost.
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NOW WHAT DO WE DO?
• Reduction of risk can be achieved with the use of relatively new technology and policies for both new installations and legacy installations.
Safety. Quality. Best Cost.
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DO YOU WANT YOUR CONTRACTOR TO GAMBLE?
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• Average importance: 9.26 (10 = high; 1 = low)
• 40 responses from major trenchless contractors in the US
How important is the issue of unmarked sewer lines to your
business?
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Claims on damaging a line that was not required to be marked by law or regulation
78%
22%
Yes
No
HAVE YOU EVER HAD TO PAY ANY CLAIMS AS A RESULT OF DAMAGING AN
UNMARKED LINE?
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Types of lines that were crossbores
18%
29%
14%
13%
16%
10%Water
Sew er
Gas
Electrical
Communication
TV Cable
WHAT TYPES OF LINES WERE CROSS BORES?
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BE SMART. PROTECT YOURSELF.
Lack ofInformation
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AVAILABLE
• One major utility’s standard
• Duke’s policies
• NPL’s Policy 22 at www.gonpl.com
• CBSA’s Guidelines for Identification of Legacy Cross Bores
Safety. Quality. Best Cost.
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ONE LDC’s STANDARD
• Verification is required using any or all:– Check manholes for depth and direction– Fish tape with Sonde transmitter– Excavate 1’ > depth of lateral near start
and end of bore– GPR, if it works– Camera before/after bore
• Pre and post construction door hangers
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DUKE’S POLICIES
• Pre-Construction: Required pre-locating before any excavation • Post Camera: Required to audit that there are no crossbores before ANY GAS UP• Contract line items to pre-locate (often via camera) and post-camera all sewer mains and laterals, services and storm drains• NPL completed 600 of almost 10,000 NPL Bore Cards in 2007
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NPL YTD Total 9956
NPL 2007 Bore Cards
1943
14081228
857776
600 597 526 464
265 246 242 198 179 17387 50 47 40 18 12 0
0
200
400
600
800
1000
1200
1400
1600
1800
2000IL
GA
MN
PG CT CI
SCA BA KS SP
SAZ PA VA CO LV PH DA NJ
NN
V
SLC
NAZ IN
Area
Num
ber o
f Bor
e C
ards
Safety. Quality. Best Cost.
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CAMERA METHODOLOGY• Trunk line with jump-off push camera’s
from house to street.
Safety. Quality. Best Cost.
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LITERATURE UNDER DEVELOPMENT
• Guidelines for locating prior to and verification post construction
• Sample Legacy Inspection Contract• Equipment manufacturers – notices• Sample ordinances
– Requiring Drain Cleaner training– Requiring Accessibility to Sewer Maps
Safety. Quality. Best Cost.
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• Educate local plumbers, rental stores, mobile home park owners … to look before they root;
• Find installed problems …before they find us.
LEGACY SOLUTIONS
Safety. Quality. Best Cost.
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A CASE STUDY• An inspection program to
inspect sewer mains and laterals for possible cross bores
• 4 priorities identified:– Mobile Home Parks– Multi-Family– Schools– Hospitals
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4 METHODS USED• Maps and Records review eliminated
– Wherever evidence of open trench installation (documented and field)
– Facilities installed after no blind bore policy began• Electronic separation
– Electronically locate depth and run of sewer lateral and gas service/main
– Separation greater than 18” required• Video past intersection point
– Used ProPipe and Orbit to complete pilot• Dig and Inspect
– As needed
Safety. Quality. Best Cost.
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VIDEO INSPECTION TECHNOLOGY
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VIDEO INSPECTION TECHNOLOGY
• ProPipe mainline lateral launcher• 8” and larger diameter lines• Self propelled• Capable of inspecting 1600’ (800’ each
direction) of sewer main and 80’ of any sewer service along the way
• Audio and video capable
Safety. Quality. Best Cost.
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VIDEO INSPECTION TECHNOLOGY
• ProPipe hand operated camera
• Typically used on lines 6” and smaller
• Range 200ft
• Audio and video capable
Safety. Quality. Best Cost.
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VIDEO INSPECTION TECHNOLOGY
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2004 PILOT
• Started in August, 2004• Late in 2004 a committee was formed to develop
program protocol company wide• 13,612 inspections in 2004 • 4 cross bores discovered
Safety. Quality. Best Cost.
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2005 PILOT RAMP-UP
• Developed and implemented public education communications program– Presentations given to over 130 residential and
commercial plumbing contractors.– Information mailed to all underground contractors
state wide• 44,229 inspections completed in 2005 with
40 cross bores discovered (.09%)
Safety. Quality. Best Cost.
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TODAY?
• As of December 2006, 91,136 inspections in high priority areas of the project found 56 cross bores (.06%)
• Started single family residence inspections in January, 2007
• As of October 2007, 18,894 inspections completed with no cross bores found
Safety. Quality. Best Cost.
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WHAT’S NEXT?
• Based on experience in the first four priority areas, the potential exists for discovery of additional cross bores at single family residences
• Potential of up to 150,000 inspections in known replacement areas
Safety. Quality. Best Cost.
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CURRENT STATS
• As of today:– About 300,000 investigations– 103 cross bores found (.03%)– 76 found during the Program– 27 found by plumbers/Roto Rooter
Safety. Quality. Best Cost.
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PILOT AREARECOMMENDATION
• Continue Program in single family residential areas and other replacement areas
• Continue Public Education Program with area plumbing contractors
Safety. Quality. Best Cost.
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STAFF RECOMMENDATION
• Expand the Program to the entire company
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“Houston, we have a problem”
-Captain James Lovell, Spacecraft Commander of Apollo 13, 1970
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THE EXPOSURE IS:
Safety. Quality. Best Cost.
• LOW FREQUENCY- HIGH SEVERITY
• SHORT TERM vs. LONG TERM
• A “PREDICTABLE SURPRISE”
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UNMARKED SEWER LINES ARE RISKY BUSINESS
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ONE BAD MOVE!!!
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- Steve EwingPast Chairman AGA,
Vice Chair, DTE
“LUCK IS NOT A STRATEGY”
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• Public
• Owner/Operator
• Contractor
GOAL: PROTECT ALL PARTIES
Safety. Quality. Best Cost.
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QUESTIONS?QUESTIONS?
Safety. Quality. Best Cost.
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A DECEPTIVELY PEACEFUL SCENE
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ON THE OUTSIDE
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THE BUILDING STARTS TO COME APART
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THE ROOF GOES UP
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THE WALLS BLOW OUT
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THE ROOF COMES DOWN
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FROM OVERHEAD
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1/3rd OF A SECOND LATER