Huon Highway - Sandfly Road - intersection safety upgrade

The new intersection was constructed from February to September 2021.

We developed the proposal for a new intersection and the $6.4 million project was jointly funded by the Australian and Tasmanian Governments to deliver improved road, cyclist and pedestrian safety, as well as improved car parking, and safer bus and freight transport movements through the area.

Completion of this project follows extensive community consultation with local residents, Kingborough Council and Huon Valley Council, industry owners and local businesses.

Based on community feedback, the Department of State Growth secured additional funding to provide a safety upgrade that addresses the community’s primary concerns – especially obscured vision and driver confusion at the intersection, as well as the inclusion of new slip lanes and the ability for buses and trucks to wait safely in the new centre median.

The work included construction of:

• a new left turn slip lane from Sandfly Road south for vehicles heading towards Huonville. Drivers will now be able to turn left at the intersection and accelerate up the hill in their own lane making it a safer entry onto the highway.
• a new deceleration lane for vehicles turning left into Sandfly Road towards Longley separates slow moving traffic from through traffic on the highway.
• the new intersection allows buses and trucks up to 12.5 metres long to wait safely in the newly constructed centre median before turning.
• a new, sealed carpark with space for 12 cars including a disabled car space to replace the previous informal car parking.
• a new, fenced footpath links the carpark with the southbound bus stop and to the new pedestrian crossing to the northbound bus stop on the other side of the highway.
• a dedicated crossing for cyclists
• new and improved lighting throughout the intersection.

We asked people for their feedback in June/July 2019 on a concept design to improve safety at the intersection.

We considered the feedback from the community and key stakeholders, and used it to develop a new concept design.

The revised concept design was presented to key stakeholders and the wider community in July/August, 2020 and includes the following features.

• The revised design has been reconfigured to address the issues of confusion in the centre of the intersection and obscured driver vision.
• The concept design includes wider medians, providing room for buses and trucks to wait safely, and traffic islands.
• One of the uphill lanes through the intersection has been removed by relocating the overtaking lane to the west of the intersection to improve safety.
• The slip lane for Huon-bound vehicles turning left into Sandfly Road south has been relocated, which will improve vision for those entering the Huon Highway from Sandfly south.
• A new slip lane into Sandfly Road north towards Longley will provide a deceleration lane for descending vehicles, which reduces the risk of turning vehicles being struck from behind.
• The design also includes improved pedestrian, cyclist and car parking facilities, better access to the bus stops, and improved lighting through the intersection.

We undertook a second round of consultation and invited feedback from the community in July 2020 on a new concept design, the elongated wide median treatment, to improve safety at the intersection (see image).

We considered all feedback, including individual feedback, as well as having consulted with Kingborough and Huon Valley Councils, local industry, business owners, and key stakeholders to determine a final design solution. This solution is based on community consultation and feedback

View the 2019 Consultation Summary Report.

View the 2020 Consultation Summary Report.

You can also view the report for a speed limit review at the Sandfly intersection below:

Community Consultation Feedback Report.

Why wasn't this being made into an overpass?

The need for an overpass solution is capacity driven. Unlike the traffic volumes at nearby Summerleas Road,  the traffic volume forecasts for the Sandfly area do not warrant an overpass. At the time the Summerleas Road intersection was designed, there was increased traffic volume predictions from the release of hundreds of lots from subdivision property developments and the close proximity of Kingston High School.

An overpass solution is constrained by the location of Northwest Bay River Bridge, the steep incline of the Huon Highway past the intersection, and close proximity of businesses and residential properties. Compulsory property acquisition would be almost certain, and would therefore be very disruptive.

This new layout is more dangerous and confusing

During last year’s consultation period, the community advised that the greatest issue with the intersection in its current form is confusion in the middle of the intersection, the inability for trucks, buses and trailers to wait safely in the middle of the intersection because there isn’t enough room and they protrude into the running lane of the highway, cars overtaking through the intersection and obscured vision caused by vehicles waiting in the current slip lanes and the centre of the intersection.

Confusion has been removed from the centre of the intersection as drivers only need to look at one set of oncoming vehicles before moving into the intersection. Obscured vision for cars waiting in the in the middle island has been removed by the relocation of the holding lines.

A solid white line has been included on the approach to the intersection heading towards Hobart, which will address safety issues caused by vehicles overtaking at speed.

An acceleration lane has been added to Sandfly Road south for vehicles heading to Huonville so these vehicles can get onto the highway in their own lane. A new deceleration lane coming down the hill into Longley will greatly reduce incidents as vehicles will be able to slow down to make this turn off the main through lanes.

The wider medians address sight line issues and allow buses, trucks and trailers to wait safely in the medians without overhanging onto the highway, which has greatly improved safety for all road users.

Cars exiting Sandfly South only have to focus on one lane of oncoming traffic which is much safer.

This new design makes it far too difficult for heavy vehicles

One of the main problems with the original intersection was the dangers associated with heavy vehicles using the intersection. Prior to the project being completed, trucks, trailers and buses would not fit in the middle of the intersection; they would either have to cross all four lanes of the Huon Highway in one movement so they do not have to wait in the middle of the intersection, or if long vehicles did have to wait in the middle, they would protrude into the highway.

The design of the centre median has been modelled using large vehicles to ensure they can make this turn.

The new design was developed in conjunction with bus operators and industry making it safer for large vehicles to wait in the centre median.

Has any private property been affected by this project?

Private property is not affected by the project. No land needs to be purchased for this project.

Will the speed be reduced?

After a speed limit review in 2019, it was decided the speed limit will not be reduced and will remain at 100km/hour. You can view the report for a speed limit review at the Sandfly intersection below: Community Consultation Feedback Report.

Why is there only one lane heading towards Huonville?

The two lanes heading towards Huonville will be reduced to one lane for an additional 300m to pass Sandfly south.

This reduction to one lane is a major safety improvement in this new arrangement.  The one lane means that traffic coming out of Sandfly South will only have to select a gap in one lane of traffic heading from Hobart, and overtaking vehicles will not suddenly appear from behind vehicles heading up the hill in the left lane while people exiting Sandfly Road are crossing the highway.

Why is there only one pedestrian crossing?

The intersection design removes the “confusion in the middle” issue, and less confusion results in a safer environment for pedestrians.  Additional crossing points may add to the confusion and the crossing is located close to the bus stop in a location where pedestrians have to negotiate the least number of lanes on the highway.

Why isn’t there a pedestrian overpass?

The number of pedestrians crossing the highway does not warrant a pedestrian overpass.

Why aren’t there pedestrian signals?

Pedestrian signals are not installed on 100km/hr highways in rural areas.

Will the carpark have the same amount of car parking spots?

There will be more parking spaces available (12), including a Disability Discrimination Act compliant parking space. The car park will be resurfaced with asphalt and the lighting improved.

Why do bikes go in the middle of the traffic island in Sandfly north and south?

Cyclists can use the median to safely cross the highway. On the side heading towards Huonville, the cyclist needs wait for gap in one lane, and the right turn lane cross the median, and wait for a gap in the right turn lane and two through lanes heading towards Hobart.  The location of the bike lanes is considered to be the safest location with the least conflict points with vehicles.

What steps are being taken to minimise environmental impacts as a result of the works?

We have completed an ecological survey on site to determine whether or not protected fauna /flora exist in the area impacted by construction. There are no endangered or protected species of flora or fauna in the footprint of the project.