This slideshow was presented on August 22 at the Shilough Baptist Church at a community meeting hosted by Councilman Kenyatta Johnson. Community members were encouraged to come and ask questions, voice concerns and learn more about the massive main break that has caused significant damage and disruption. Representatives from PWD, PECO, Streets Department, PGW, Verizon, and other City agencies were in attendance.
Z Score,T Score, Percential Rank and Box Plot Graph
Community Meeting: 21st & Bainbridge
1. Main Break: 21st and Bainbridge
SOSNA Sponsored
Community Meeting
August 22, 2012
2.
3. WHAT HAPPENED?
• Break in 48-inch transmission main on
Sunday, July 22
• Resulting in washout of intersection and
flooding to approximately 70 properties
• PWD pumped basements, cleaned
sidewalks and streets with the assistance of
the Streets Department and replaced hot
water and house heaters as needed
• PWD Claims representatives worked with
residents/businesses
Philadelphia Water Department
4. WHY DID IT BREAK?
• Analysis performed by an independent
consultant on the broken section of pipe
showed that age/corrosion was not a
factor
• Forensic evidence to pinpoint contributing
factors not available as pre-existing
underground conditions washed out with
break
Philadelphia Water Department
5. RESTORING THE INTERSECTION AND
THE COMMUNITY
• PWD “first in” to make repairs
• PECO, PGW, Verizon are following
• Restoration of damaged streets and
sidewalks last component
Philadelphia Water Department
23. A broken strap could result in serious injury and further damage to infrastructure.
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26. With the 36” main out of the way, workers attach strapping to the 48” main.
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28. A good view of the blow out on the 48” cast iron transmission main.
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34. WHY WATER MAINS BREAK
• Water mains fail when the stresses placed upon
them are greater than the strength of the pipe.
• External forces on a water main may increase
over time due to traffic loading, temperature
changes, other underground work that impacts
the water main either immediately from direct
contact or over time from movement or bearing
on the main.
Philadelphia Water Department
35. WHY WATER MAINS BREAK
WHY WATER MAINS BREAK CONTINUED…
CONTINUED…
• 50% of all water main breaks occur during the winter
months of December, January and February.
• Water temperatures in the main and the ambient air
temperature drops dramatically and cause smaller
mains to contract and become brittle. In addition,
the ground freezes and expands exerting additional
stress on the main.
• Transmission mains are large, thick walled pipes
that are not impacted as much from the cold
weather
• Philadelphia experiences less than 5 transmission
main breaks (pipes16-inches and greater) on
average a year.
Philadelphia Water Department
36. WHY WATER MAINS BREAK
WHY WATER MAINS BREAK CONTINUED…
CONTINUED…
• Philadelphia has been monitoring main breaks for
decades. The number of main breaks occurring each
year is highly dependent on the severity of the winter
weather; milder winters mean fewer breaks.
• The national annual average for water main breaks is
270 breaks per 1,000 miles of main. PWD’s current
average is 230 breaks per 1,000 miles of main annually,
less than the national average.
• This lower rate is due to a water main replacement
program begun thirty years ago and PWD’s leak survey
and corrosion control programs.
Philadelphia Water Department
37. HOW ARE WATER MAIN BREAK
AVOIDED?
• Leak Detection
• Water Main Replacement
• Cathodic protection
• Corrosion testing
• PWD just conducted a focused leak detection
program in this community and found one leak on
a hydrant which is scheduled for repair
Philadelphia Water Department
38. PECO, PGW & VERIZON
• PECO began work on August 13 – date PWD
completed their work. Work includes: removal of
damaged conduit, installation of new conduit
and installation of new manhole
• PGW will begin work once PECO manhole
installed. Work includes: relocate gas main
along north footway on Bainbridge Street
• Verizon - Work includes: installation of new
conduit in intersection. Completed work on
August 21
Philadelphia Water Department
39. Repair Timeline
REPAIR TIMELINE
7/22-8/13 8/13-8/19 8/20-8/26 8/27-9/2 9/3-9/9 9/10-9/16 9/17-9/23
PWD Repair Complete
Mains, etc.
PECO Remove Install New Conduit &
Conduit Manhole
PGW Relocate
New
Gas Main
Verizon Service Removed Conduit Replacement
Restored Damaged Scheduled
Facilities
PWD Paving
Restoratio
n
Restoration of Streets and
Sidewalks