The intersection upgrade at Frankston-Dandenong and Thompsons Roads in south east Melbourne was set to take five months to construct. When coronavirus restrictions eased traffic, the team got to work hatching a plan to complete works in just five weeks.
Before coronavirus restrictions came into place the roundabout at the intersection of Frankston-Dandenong Road and Thompsons Road saw 58,000 vehicles daily.
It is a connection point for those living in the Frankston, Carrum Downs, Cranbourne areas and working in the industrial hub of Dandenong. The Carrum Downs area is set to see an increase of over 4500 people by 2026, meaning infrastructure upgrades will be crucial.
As part of the major Thompsons Road Upgrade project, BMD Constructions were contracted to remove the roundabout at Frankston-Dandenong Road and replace it with a signalised intersection.
The construction of the intersection was set to be completed in five months but with the coronavirus reducing traffic, the team at Major Road Projects Victoria (MRPV) saw an opportunity to complete the project in a fifth of that time.
Program Director Brendan Pauwels says the team were seeing a drop of around 30 per cent in traffic volumes while people were at home.
“We got planning as to whether we could close the intersection to fast track the completion of the works and then from there it snowballed and we came up with a plan and put it into action,” he says.
MRPV decided to perform a five-week total closure of the intersection, which would allow the team enough time to complete construction.
“We pitched this to the State Government as we thought it was possible. We did the work around what would need to be put in place to enable the fast tracking to happen,” Mr. Pauwels says.
“A lot of work was needed to understand traffic movements and the impact that might have on motorists and also local residents and businesses who would have their access altered.”
MRPV estimations showed there would be around a 20 to 30 minute delay for motorists during the five-week period, as opposed to an approximate 10-minute delay over the longer period of construction for five months.
“We put together a communications and stakeholder strategy and a traffic management strategy. Then we went to government and said we think we can do this, and we can save four months of ongoing construction,” Mr. Pauwels says.
To aid with the fast tracking of the project, the contractor BMD Constructions were already conducting early works for the intersection including the relocation of services.
“The planning that we did with BMD has been very thorough in terms of getting a fool proof program for activities that need to happen in the five weeks,” Mr. Pauwels says.
MRPV worked with BMD Constructions to map out the productivity rates that could be achieved in the time frame, how the supply chain could keep up with the plan and what the backup plans were for materials, subcontractors or even redundancy in equipment on site.
“We also had to work through how they work in a COVID-19 safe manner. We had to manage the shift handover for day and night shifts, so we sat down and worked through this with them, did a workshop for half a day on all of these sorts of processes to ensure the project was planned in an efficient and safe way,” he says.
In the end it was decided five weeks would be sufficient, having the fifth week as a buffer for any unexpected delays due to weather or uncontrollable factors.
The first week of construction began at the start of Queen’s Birthday long weekend. This allowed the team to shut down the roundabout with minimal disruption and begin demolishing the existing road pavement.
“Full access to the intersection meant we could change the construction technique, the contractor pulverised the whole existing road pavement and then we were able to reuse that as road base,” Mr. Pauwels says.
When levelling out the intersection, Mr. Pauwels says there were sections nearly a metre deep that needing filling so existing pavement was used as road base alongside imported fill materials.
The first week of construction also saw significant underground works for drainage and other essentials to set up for the beginning of the pavement’s construction.
For the next two weeks the focus was on the pavement layers, this included importing 8000 tonnes of crushed rock and then applying the asphalt layers with around 11,000 tonnes placed.
At the time of writing the construction team is looking ahead to weeks three and four.
“At week four we have a decision point as to whether we finish everything. The wearing course can only be placed in temperatures above 10 degrees, otherwise it becomes brittle,” Mr. Pauwels says.
“We then have a week of contingency in the program to allow for weather. We are doing this project in winter which has different challenges as it’s colder, there are less hours of daylight and fog can confuse the machine’s GPS systems.”
The challenge of re-planning a five-month project to be conducted in five weeks was most evident following the decision to completely cut off the intersection.
This decision required extensive planning and communication to minimise disruption to road users and residents in the area.
“The biggest challenge was traffic. The first thing we had to do was figure out where the vehicles would go if the intersection closed. We bought in a traffic modelling company to do assessments of where those vehicles might go,” Mr. Pauwels says.
He says the company provided the project team with hotspots of where key delays may occur when vehicles take alternative routes.
“To try and smooth the effects out as best as possible we put in temporary measures. At Hall Road and Frankston-Dandenong Road we changed the intersection from one right hand turn lane to double turning lanes. To do that, we banned the opposing right turn lane because there isn’t enough room for both to turn at the same time but that is a much lesser demand movement,” Mr. Pauwels says.
Then the team installed temporary traffic signals at the intersection of the Western Port and East Gippsland Highways. Mr. Pauwels says this was seen to be a pressure area for the afternoon peak as people returned from employment clusters in Dandenong.
The signals helped to facilitate a safe right hand turn to create access between the two roads.
As part of the project, the team are also working with a full-time traffic management professional at the Department of Transport. This person can review traffic signals and alter them in real-time to best improve traffic flow.
“We have real-time monitoring in place and lots of VMS boards to support detours. Around five or six of them have real-time information and that is to try and help influence motorists to make the best decision and smooth out congestion,” Mr. Pauwels says.
To keep public transport on track the crew allow busses through the intersection on their given timetable, resulting in minimal delays and changes to the bus network in the area.
With completion expected in just five weeks, any traffic disruptions are expected to be short lived. Once the new intersection is constructed and in operation it is expected to be able to cater with demand in the area from increased population.
“The upgrade should provide a significant benefit for motorists in the morning and evening peaks, we are saying five to ten minutes for motorists to be able to get through what was a bottleneck,” Mr. Pauwels says.
“It was a pretty bold call for us to do this, but I think it’s something that we are aiming to learn a lot from during the closure to see how we might plan some future projects or road upgrades,” he says.
(Please note this story was written in late July and featured in the August edition of Roads & Infrastructure magazine)
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