Gobbagombalin Bridge Duplication
The Gobba Bridge is a key piece of infrastructure that forms part of the the Olympic Highway, connecting communities north of the Murrumbidgee River with Wagga and further south to Albury and Melbourne. The Bridge was constructed in 1997 as a two-lane highway and crosses the Murrumbidgee River at Wagga Wagga. It is vital in times of flood as other river crossings are often under water and inaccessible for long periods of time.
As the population of the city has grown, residential subdivisions have established north of the city and the University has increased its capacity. The construction of the original two-lane bridge in 1997 has facilitated significant economic development for the city, opening up large parcels of land for residential subdivision and ensuring the University remains suitably connected to the city. A duplication of the bridge is likely to deliver further economic benefit as the city continues to expand further north and retail precincts are developed to service the growing population.
Demand for residential development in suburbs such as Estella, Boorooma and Gobbagombalin has been strong and consistent, increasing the population of residents in suburbs north of the river from just 2,000 people in 2006 to an estimated 8,000 in 2016, an increase of over 300%. In addition, the student capacity of Charles Sturt University’s campus is approximately 3,200. Census data suggests approximately 65% of Wagga Wagga residents travel to work by car and a further 5% travel by car as a passenger. Therefore currently about 5,200 people are likely to commute locally on the bridge at a minimum of twice daily, accounting for more than 10,000 trips.
A further 1,700 blocks of residentially zoned land are yet to be subdivided north of the bridge, potentially boosting the area’s population to over 13,000 within the next 10 years based on current rates of development and average household sizes. As residential activity continues to occur north of the city consideration must be given to the inevitable congestion as local traffic mixes with regular users of the busy highway.
Compounding the congestion caused by residential development, commercial investment by heavy industry at the Bomen Business Park and establishment of the Riverina Intermodal Freight and Logistics Hub will encourage more heavy vehicle movements across the bridge.
RMS traffic counts on the bridge in 2010 indicate over 13,300 movements each way on a daily basis. This is an increase of 33% from counts in 2006 of 10,000 movements. The following table indicates the traffic movements on the bridge using the same growth rate evidenced between 2006 and 2010, approximately 7% per year.
STRATEGIC PLAN 2017 9 The projected movement data suggests traffic on the bridge will double between 2015 and 2025, therefore planning should begin now to prepare for the inevitable need to accommodate higher demand.
In 2007 the Sheahan Bridge along the Hume highway at Gundagai was duplicated at a cost of $78M. In 2006 prior to the project’s completion traffic counts along the highway were 15,500 at locations north and south of Gundagai, less than the current movements across the Gobba Bridge.
Pressure on the two lane Gobba Bridge is high, with heavy congestion often occurring during the morning and afternoon peak hour. In addition, traffic flow on the bridge is significantly affected by accidents and slow traffic such as heavy freight or machinery, with the potential to cause lengthy delays and long diversions. The bridge is also unable to support alternative modes of transport such as walking or riding.
Forward plannning, the allocation of funds and establishment of indicative timelines must progress now to ensure the bridges capacity is increased and sufficient for the expected increases in cars and freight.
Traffic on the Gobba Bridge is expected to double within the next 10 years.
Cost Estimate: No
Wagga Wagga City Council
Committee 4 Wagga
Developers and Businesses
Commence planning and identify future funding sources to ensure duplication of the bridge can occur when demand exceeds capacity.