❓ A WA parliamentary question on notice addresses traffic modelling for the Roe Highway extension, questioning its impact on Leach Highway traffic and the justification for its $700 million expenditure, given predicted congestion levels. The Minister's response provides some figures and justifications for the project.
AnsweredQoN 676Legislative Council
QuestionView source ↗
ROE HIGHWAY EXTENSION — TRAFFIC MODELLING
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
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
AnswerView source ↗
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 the number of 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.
(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 the number of 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.
(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 the number of 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.
(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 the number of 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.
(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?
(c) in seven intersections there is no increase in congestion?
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 the number of 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.
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 the number of 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.
(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 the number of 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.
(2) Traffic modelling indicates up to a 10 per cent decrease, with a 15 to 20 per cent reduction in the number of 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.
(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.
(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.
(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 the number of 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.
(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 the number of 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.
(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 the number of 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.
(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?
(c) in seven intersections there is no increase in congestion?
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 the number of 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.
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 the number of 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.
(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 the number of 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.
(2) Traffic modelling indicates up to a 10 per cent decrease, with a 15 to 20 per cent reduction in the number of 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.
(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.
(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.
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