Roe Highway extension - traffic modelling

Submitted by Louise Sales on Wed, 31/08/2011 - 15:20

Extract from Hansard
[COUNCIL — Wednesday, 31 August 2011]
p24b-24b
Hon Lynn MacLaren; Hon Simon O'Brien

ROE HIGHWAY EXTENSION — TRAFFIC MODELLING

Hon LYNN MacLAREN to the minister representing the Minister for Transport:

I refer to traffic modelling for the Roe Highway extension.

(1) What are the predicted total daily traffic flows on Leach Highway with and without the proposed Roe
Highway extension in 2021 and 2031?

(2) Does the modelling predict that the Roe Highway extension is unlikely to markedly decrease the
amount of traffic on Leach Highway?

(3) How is the expenditure of approximately $700 million justified, given that without the Roe Highway
extension by 2031 —

(a) only nine of the 17 intersections measured are predicted to be more congested;

(b) in seven of these nine intersections the predicted levels of increase would hardly be
noticeable because they are already significantly congested; and,

(c) in seven intersections there is no increase in congestion?

(4) At which intersections does modelling forecast congestion will worsen, causing forced traffic flow if
the proposed highway extension is completed?

Hon SIMON O’BRIEN replied:

I thank the honourable member for some notice of this question.

(1) Please refer to question on notice 962.

(2) Traffic modelling indicates up to a 10 per cent decrease, with a 15 to 20 per cent reduction in trucks.

(3) Roe Highway extension will provide a high standard east–west link with forecast traffic flows of up to
75 000 vehicles per day in 2031. Those vehicles would otherwise have used the existing road network.
The extension will provide increased road safety and transport cost savings of over $4 billion between
2016 and 2031. If Roe Highway is not extended, traffic will divert onto local roads as many major
intersections are already operating at full capacity.

(4) Congestion at most of the existing intersections of local roads in the region will decrease. Intersections
on Stock Road, in particular those south of Roe Highway, will have increased congestion when Roe
Highway is extended. Stock Road is ultimately planned to be upgraded to a six-lane fully grade-separated
highway to address this congestion