Durkin and Downer collaborate on a challenging pavement maintenance project
Durkin Construction has been fortunate to work with Downer over the last two decades, and we have collaborated on some major projects in Sydney.
It all started with asphalt and stabilisation projects 20 years ago, and now Durkin is Downer’s provider of choice when it comes to engineering and service locating needs, and maintenance contracts.
On pavement maintenance projects, one of Downer's biggest challenges is completing their works without damaging shallow utility services. With this in mind, they decided to engage Durkin – their trusted potholing and service-lowering contractor for the last 20 years – as they wanted to minimise the risk of service strikes during the project.
The Challenges and Scope of The Project
Pavement maintenance in the greater Sydney basin is risky as it’s highly possible to hit shallow services. It can disrupt the supply of everyday utilities and can cause pavement damage from broken water services. Additionally, there’s also a risk of explosion and fire.
According to Durkin Construction Operations Manager Kerry Constanti, Durkin have the expertise and are well-equipped to deal with this common problem. And, that’s why Downer Infrastructure knew Durkin were the experts for this project.
“Shallow services pose a great risk to the successful completion of pavement maintenance in the greater Sydney basin,” Kerry said.
“Durkin provides a premium locating service and also offers the lowering of the at-risk shallow services.
“We are eliminating the risk of pavement damage from broken water services and fire and explosion from damaged gas services”.
The scope of the project included:
EM and GPR scans for locating any underground services in the area
Potholing shallow or unknown services to confirm their actual depth and alignment
Lowering the services to the required depth to ensure adequate pavement coverage between the service and base of the construction works to ensure a uniform pavement thickness is constructed.
“After the scans and services were located, we had to lower these services to avoid pavement failure that often happens when contractors lift up over the shallow services and install a reduced pavement over them,” Kerry explained.
“Durkin possesses the expertise and skills to analyse the data from the field and to apply engineering logic to develop a solution for dealing with this all too common problem,” he affirmed.
Durkin Taking Charge and Delivering a Successful Result
When Downer reached out to Durkin for this new project and shared the project scope, all the details were reviewed thoroughly to put together a fail-safe plan. With exceptional project management, the project went accordingly, with no delays or issues.
Once the project plans were determined, Durkin crews were deployed at the worksite to run EM and GPR scans to locate any shallow services in the area. The scans revealed two shallow water services that could hinder the pavement construction. Using the information obtained from the scans, Durkin proposed a pothole plan to the client.
“When we received the project scope from Downer, we obtained the BYDA plans, review and consolidated it into a single document,” said Kerry.
“We then put our teams to work, completing the service locating process with EM and GPR scans. This information is recorded on a maps image, and after reviewing the information, a pothole plan was proposed to the client.”
Upon receiving the client’s approval, potholing was completed, and the actual information of the shallow services learned in this process was updated in the original plan. This led to the successful organisation and implementation of service lowering, and a full-depth asphalt pavement was constructed.
Durkin also made sure the shallow services are lowered as per the approvals from the relevant authorities; Sydney Water and the Local Council.
“We wanted to make sure a thorough job was done and that it is in line with the state laws and regulations that apply,” Kerry said.
“So, we utilised all the available resources and took a meticulous approach to plan every phase of the project. The plan was updated with the information we obtained from the scans to ensure when our teams go out there to carry out the service-lowering phase they have the accurate information at hand.
“Based on the information we learned, we organised the service lowering process and successfully managed to lower 2 water services, leading to the construction of a full-depth asphalt pavement without having to lift up and constructing a shallower pavement over the services, thus ensuring the integrity and performance of the pavement well into the design life,” Kerry added.
Key Challenges and the Solutions
Durkin crews were faced with several challenges during the project. First and foremost was to complete the trench work while managing live traffic and buses.
The project manager decided to put a full traffic detour in place to manage the traffic. Furthermore, the crews did the trench work at night, heavily reducing the number of buses that had to be managed through the site.
Another challenge for Durkin was to make sure they gathered accurate information on the exact location of the services and how deep they are.
“The challenge was even bigger in locating the gas services as they don’t follow the information mentioned by the network provider,” said Kerry.
“We used the gas tracker to further find a gas service connection and confirm its location which was indicated crossing the road by the Jemena information. However, it was found to be connected to the gas main on the near side and not crossing.”
Despite all the challenges, Durkin did a thorough and professional job, creating more certainty from uncertainty on the project.
Our planning was spot on, and we used all our experience to ensure the project is completed as per the industry standards and all the requirements of any relevant authorities are fulfilled.