DBYD Case Studies
Case Studies
Australia’s National ReferralNational Service for Information Pipes & Cables Pipes & Cables www.1100.com.au Australia’s Referral Serviceon forUnderground Information on Underground
DBYD Case Studies
What is Dial Before You Dig? Dial Before You Dig is a non-profit referral service. It represents most of Australia's underground asset owners. Dial Before You Dig connects users involved in all forms of excavation with the infrastructure owners of underground services in that area. You tell us where you plan to dig and we pass on the referral to owners of underground infrastructure in that area. They send the information directly to you, generally within two business days. Some utilities will send information by email that can arrive very quickly while information sent by fax or post may take longer. Some owners of underground infrastructure may also contact you by phone to discuss your proposed works or they may ask you to go to their office to discuss the job in more detail. Over the years, we’ve seen a wide variety of disruptions from excavators unwittingly digging up underground infrastructure. Ruptured sewerage pipes, explosions from gas mains and even deaths from contact with underground electricity cables have occurred. The severity of incidents varies greatly – as does the resulting impact. In the past, these damages have led to communities being isolated from telephone services including the 000 emergency number. Police, Ambulance and Fire Brigade services have been forced to rely on backup communication networks. For someone in Australia’s remote communities, a lack of communication can lead to fatal results. There is also the personal impact of an incident to the individuals responsible. Serious injury and death does happen. If you negligently damage underground pipes or cables you may be faced with criminal prosecution and significant damages claims. Commercial damages have been known to run into the millions of dollars leaving some businesses bankrupt and not able to function. Dial Before You Dig has a single contact number between 8am and 5pm on working days - 1100 Dial Before You Dig is online 24 hours a day, seven days a week- www.1100.com.au
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
Consequences of Damage When you hit a pipe or cable onsite, the costs go beyond just the cost of repair. The first impact is disruption to the job. People and equipment stand idle while the pipes or cables are repaired. Sometimes it can take weeks for repairs to be made. The second impact is the cost of repairs. Typically Telstra copper cables cost $50 a pair to repair. The sounds cheap until you realise that an 800 pair cable might cost $40,000. Natural gas suppliers have a calculation for lost gas that takes into account the size of the hole, the gas pressure, size of the pipe and time taken to cut the gas off. The charges for this begin in the hundreds of dollars and increase from there. The average electricity repair cost in New South Wales is around $25,000. The record to repair a single electricity cable is $1 million. Third party losses are the third impact of damage. These are the costs to people and businesses who cannot function that day because their gas, electricity, water or communications supply was cut off. Telecommunications is the most expensive network for third party losses. A damage to an 11 kV electricity cable or steel gas main can affect supply to many people and lead to significant third party losses. There have been two damages in the last two years where third party losses have been over $800 million. To put that into perspective, look at the following table. The table ranks the cost of natural disasters in Australia, with the cost converted to 2006 dollars. The table does not include the Queensland floods and cyclone of January 2011. The two damages would fit into this table in their own right. Every year around Australia there is around $2 billion in damages to underground pipes and cables. These costs are from repair costs, third party losses and disruption to work. Because this $2 billion is spread across Australia every day of the year, it’s easy to miss. But chances are you have been affected by one of these damages – either through having to pay to repair a pipe or cable that you have damaged, or in business loss due to someone else’s damage.
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
Source: Crompton and McAneney The cost of natural disasters in Australia: the case for disaster risk reduction The Australian Journal of Emergency Management, Vol. 23 No. 4, November 2008
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
How do I dig safely? All excavators have a Duty of Care to protect underground infrastructure when digging or excavating. Seek information on underground networks well in advance of digging. These are available from infrastructure owners through Dial Before You Dig. Depending on the method used, can usually be provided within two business days. Whenever the scope of works changes or plan validity dates expire, you must submit a New Dial Before You Dig enquiry. Different plans have different life spans. Onsite inspections for identifying the presence of underground networks should always be performed. Should you require an onsite location, contact the infrastructure owners directly. Constructors/Excavators must dig by hand when excavating or working close to underground infrastructure. In the event that damage to an underground infrastructure occurs, you must advise the infrastructure owner immediately. Avoiding underground pipe and cable damage is as simple as having the right tools, the right skills and the right information. It is integral to the planning stages of every project to obtain underground network information. Lodge your enquiry with Dial Before You Dig and participating owners of underground infrastructure located within your proposed work site will provide you directly with information – usually within two business days. Check this information thoroughly to see if it relates to the area you requested and make sure you clearly understand it. If you are unsure about what the symbols mean or how to proceed always contact the relevant infrastructure owner FIRST before commencing any excavation work. When commencing work near underground networks, it is important to observe minimum depths and clearances as stated clearly in the information and on the plans provided by the infrastructure owner. Underground networks may be at any depth below the surface. Infrastructure owners can provide information about their requirements in regard to safe digging practices. This may include manually exposing the infrastructure. Simply contact the owner of the underground infrastructure to find out how to work safely around their networks. Their contact details are provided on the Enquiry Confirmation Sheet you receive from Dial Before You Dig or on information your receive from the infrastructure owner.
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
Unfortunately, not all of Australia’s underground infrastructure owners are members of Dial Before You Dig. Therefore never assume that the plans you receive from your enquiry represent all underground infrastructure in your excavation area. Please Note: Underground location plans provide information about the presence of underground infrastructure only; they do not pinpoint the exact location. You should use the plans as a guide to physically locate the underground infrastructure before you start the excavation work and take the necessary steps to protect this infrastructure. For more information about locating and working near underground networks, contact the relevant infrastructure owners. The Four P’s of Safe Digging: Plan – Plan your job. Use the Dial Before You Dig service at least two business days before your job is due to begin to receive the information you need to carry out a safe project. Pothole – Potholing (digging by hand) is a method to assist in establishing the exact location of all underground infrastructures. Protect - Protecting and supporting exposed infrastructure is the responsibility of the excavator. Always erect safety barriers in areas at risk to protect underground networks. Proceed – But ONLY when you have Planned, Potholed and put the Protective measures in place. This may include tool box meetings, Job Safety Analyses, Work Method Statements and Permits to Excavate.
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
Why Can’t Anyone Guarantee Depth and Alignment of Pipes and Cables? Many pipes and cables have been under the ground for decades. In major cities it is common for networks to be up to 100 years old. The ground over them has been often raised and lowered and the roads have been realigned or widened since the pipe was laid. Every change means the relative depth and alignment of existing pipes and cables have changed. Networks that have been in the ground for decades will not have sand backfill, marker tape or any of the modern ways of marking their presence. Older style pipes are made of materials such as terracotta (earthenware) or asbestos cement, which are brittle and require care.
This is an example of Telstra earthenware and asbestos cement pipes. There are many of these still in use. This is an example of older-style electricity conduits with “electric” bricks as a warning marker.
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
Case Study 1 Illegal and unauthorised modifications of utility plant The principal contractor had the task of putting in road crossing conduits for future insertion of different utilities. The road crossings for the new water main and recycled water main were omitted. Under the direction of the principal, a plumber dug down and found a white conduit close to where the two mains should have been installed.
The plumber cut out 1.5m of the white PVC conduit and the cables located in it. He inserted both the water main and the recycled water main in the telecommunications conduit and buried his work.
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
Case Study 2 Stormwater pipes The plumber had the task of putting in a new 225mm stormwater pipe connecting a new building to the existing council storm water pipe in the footpath. Dial Before You Dig plans had been ordered by the builder about a year before this damage. Neither the plumber nor the builder could find a copy of these plans, so excavation was carried out without any plans onsite. The plumber came across three separate power cables with thick PVC marker strips on top. The strips were thrown out with the soil.
The plumber came across three separate power cables with thick PVC marker strips on top. The strips were thrown out with the soil. Continuing across the footpath, they found an old asbestos cement conduit and smashed it. They then discovered that telecommunications cable ran through this conduit and made the assumption they had found all telecommunications networks at the site.
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
They proceeded down another 1.2m and came across a concrete encasement. They made the assumption that it must have been spare concrete that had to be removed because it was in the way of their new stormwater pipe.
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
An excavator was called in with a jackhammer and the operator began to remove the concrete. In the process of removing the concrete they damaged multiple conduits and cables both copper and fibre feeding and servicing local, state and international telecommunications customers.
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
Case Study 3 Footpaths The local Council contracted a concreter to reinstate a footpath after the power company had upgraded their power cables. The concreter assumed that all existing conduits and cables were deep enough to avoid damage. This area is very old and the infrastructure in the ground has been there for over 80 years. Wooden pegs were used to hold in the formwork for the new path.
In the process of driving these pegs in the ground, they penetrated through earthenware pipe housing major telecommunication cables and caused a large outage to the telephone network system in the local area.
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
Case Study 4 Telecommunications The State government had a project to expand and upgrade freight lines. The principal civil contractor had the task of clearing the land and making way for new tracks. In the process of site preparation the civil contractor barricaded the telecommunications network, denying the telecommunications company access to their plant. The telecommunications network was also damaged three times.
As a result the telecommunication s company took out an injunction on this site, stopping the civil contractor from working until full access was restored to telecommunication s plant and a budget was put in place to relocate services that had been affected by their civil works.
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
Case Study 5 Footpath Collapse At this site a retaining wall holding up a footpath collapsed. Council brought in contractors to rebuild the retaining wall. In the process of replacing the wall the contractor realised that older asbestos and earthenware pipes needed to be relocated.
Instead of arranging with the utility to relocate their assets, the contractor decided to move the conduits himself. In the process of doing this he damaged the conduits and the cables in them, causing serve disruption to local services.
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
Case Study 6 Service Pits A builder needed to raise the footpath by 600mm. In order to get the footway to the correct height the builder buried many service pits and modified utility networks without authorisation.
Cables in the pits and manholes affected by these modifications were no longer accessible to utility staff. The affected utilities repaired their assets and passed the cost to the builder..
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
Case Study 7 Poor Planning A local builder had just completed a high rise building. A major manhole was located in the footpath, right where the proposed new driveway was intended to be. When the builder approached the utility that owned the manhole, he was informed that it would extremely expensive to relocate it.
As a result of this poor planning the driveway had to be built to half the designed size with a traffic light to manage vehicle flow.
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
Case Study 8 Manhole care This builder was charged thousands of dollars for damaging a cable by parking on a manhole lid, which then snapped and fell in the hole. The driver was fined by the Council for driving on the footpath, the Police gave him an infringement notice and the affected utility gave him a bill for the repair of the damaged network.
The utilities bill was easily the most expensive of the three penalties.
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
Case Study 9 Care When Drilling The Case Study presented here was a major network damage site at Mt Gravatt, located just south of Brisbane.
The damager was drilling a series of holes with a 500m auger drill when they drilled through the Telstra major conduit route causing mass disruption to over 100 thousand customers including mining giant Xstrata and Television broadcaster channel 7 Gold Coast.
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
On investigation it was found that they did not engage an Accredited Plant Locator (APL) to verify the location of the network cabling.
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
The assumption made by the damager was that there was no network in the vicinity as they were drilling well inside what they thought to be the property boundary, however this is where the error occurred. Had they have surveyed the actual property boundary they would have found that it does not follow the fence line or road.
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
Telstra's Network Integrity is now working the region C&M team to identify the best repair solution for the conduit route as well as organising some cable awareness presentations for the damager to prevent future issues.
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au
DBYD Case Studies
Case Study 10 Care when excavating This incident happened just outside The NULCA service centre at Manly vale.
The company was excavating to run a new conduit for AusGrid. They had supposedly located but markings were very poor and inadequate after observing. It appears they hit the House connection to the Main. There was no pot holing done to confirm service positions. This could have been avoided with clearer markings. It happened on a Friday afternoon and took over 4 hours to repair.
Australia’s National Referral Service for Information on Underground Pipes & Cables
www.1100.com.au