Transmission Gully Motorway
Encyclopedia
The Transmission Gully Motorway is a 26 km motorway proposed for Wellington
, New Zealand
.
along the coast road between the Kapiti Coast
, Pukerua Bay
and Porirua
. From SH1 at MacKays Crossing, north of Paekakariki
, the route rises steeply to the Wainui Saddle and follows Transmission Gully
down to Porirua Harbour
's Pauatahanui Inlet. It continues south around the outer edge of the Porirua urban area, at one point crossing a 300-metre-long and 90-metre-high bridge, and rejoins SH 1 at the boundary of Porirua and Tawa
. The length is 26 km, with a maximum gradient
of about 8.3%.
, in preparing its Western Corridor Plan, initially rejected Transmission Gully as unaffordable, preferring to upgrade the existing coastal route, but changed its position after public consultation.
Transport Minister Steven Joyce
announced government commitment to the project on 15 December 2009, with a project cost of NZ$1.025 billion. The project has yet to be finally approved, but construction is expected to start in September 2014 and be "substantially completed" in 2020.
Supporters claim that it will improve access to Wellington City
, arguing that the existing coastal route is too congested, is accident-prone, and could be damaged in a serious earthquake. Peter Dunne
, MP for Ohariu-Belmont, says that "[i]mproving Wellington City's northern access and egress is a vital key to the future economic performance and prosperity of the whole region, and the Transmission Gully highway is a vital link in that chain".
Opponents of Transmission Gully state that there are better ways to improve access to Wellington. The fact that such a highway would require an extremely steep gradient on its northern-most end and would thus not actually offer any improvement over the existing coastal highway has been recognized by most opponents. The route that the highway must take is along the major fault line of the region, which would make it at least as earthquake prone as the existing coastal highway.
Some suggest that the existing coastal route should be upgraded, rather than building a completely new route. This was the original recommendation of the Regional Council, and was put forward as the primary alternative to building Transmission Gully. Public submissions to the Council were in favour of Transmission Gully, and the Council has changed its stance in response.
Opponents of upgrading the coastal route say that doing so would cause significant disruption to the communities it passes through, whereas Transmission Gully avoids urban areas. The former Mayor of Porirua, Jenny Brash
, has said that an upgrade would generate large numbers of complaints from Porirua residents, and would therefore have difficulty receiving resource consent.
Others, such as the Green Party
and the lobby group Option 3, believe that the money would be better spent on improving Wellington's public transport
, particularly the existing rail line. They argue that the original choice between building Transmission Gully or upgrading the coastal route was a false dichotomy, and that in reality neither option is necessary or desirable.
, has described the project as "unaffordable". It has been suggested that making Transmission Gully a toll road
would help resolve this problem, although no decision has yet been taken on the matter, and tolls would only cover a fraction of the funds necessary to build the highway.
Wellington
Wellington is the capital city and third most populous urban area of New Zealand, although it is likely to have surpassed Christchurch due to the exodus following the Canterbury Earthquake. It is at the southwestern tip of the North Island, between Cook Strait and the Rimutaka Range...
, New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
.
Route
It is planned to replace the current State Highway 1State Highway 1 (New Zealand)
State Highway 1 is the longest and most significant road in the New Zealand roading network, running the length of both main islands. It appears on road maps as SH 1 and on road signs as a white number 1 on a red shield, but it has the official designations SH 1N in the North Island, SH 1S in the...
along the coast road between the Kapiti Coast
Kapiti Coast
The Kapiti Coast is the name of the section of the coast of the south-western North Island of New Zealand that is north of Wellington and opposite Kapiti Island. It falls under the jurisdiction of the Wellington Regional Council...
, Pukerua Bay
Pukerua Bay
Pukerua Bay is a small seaside community at the southern end of the Kapiti Coast, New Zealand. In local government terms it is the northernmost suburb of Porirua City...
and Porirua
Porirua
Porirua is a city in the Wellington Region of New Zealand, immediately north of the city of Wellington, with their central business districts 20 km apart. A large proportion of the population commutes to Wellington, so it may be considered a satellite city. It almost completely surrounds...
. From SH1 at MacKays Crossing, north of Paekakariki
Paekakariki
Paekakariki is a town in the Kapiti Coast District in the south-western North Island of New Zealand. It is 22 km north of Porirua and 45 km north-east of Wellington, the nation's capital city....
, the route rises steeply to the Wainui Saddle and follows Transmission Gully
Transmission Gully
Transmission Gully is a chain of sleep-sided, isolated valleys in the Wellington Region of New Zealand. It runs approximately north-south between the Kapiti Coast and Tawa, through the hills behind the city of Porirua....
down to Porirua Harbour
Porirua Harbour
Porirua Harbour is a natural inlet in the south-western coast of the North Island of New Zealand. The city of Porirua, one of the four cities in the Wellington conurbation, surrounds it. The city centre is to the south of the harbour....
's Pauatahanui Inlet. It continues south around the outer edge of the Porirua urban area, at one point crossing a 300-metre-long and 90-metre-high bridge, and rejoins SH 1 at the boundary of Porirua and Tawa
Tawa, New Zealand
Tawa is the northernmost suburb of Wellington located between Churton Park and Porirua in the North Island of New Zealand. It takes its name from the broadleaf tree, which was once prolific throughout the area, although its most famous tree is the Bucket Tree, a group of large macrocarpa with the...
. The length is 26 km, with a maximum gradient
Slope
In mathematics, the slope or gradient of a line describes its steepness, incline, or grade. A higher slope value indicates a steeper incline....
of about 8.3%.
Construction
Proposals have existed for some time, but it was only late in the first decade of the 21st century that serious steps were taken towards construction. The Greater Wellington Regional CouncilWellington Region
The Wellington region of New Zealand occupies the southern end of the North Island.-Governance:The official Wellington Region, as administered by the Wellington Regional Council covers the conurbation around the capital city, Wellington, and the cities of Lower Hutt, Porirua, and Upper Hutt, each...
, in preparing its Western Corridor Plan, initially rejected Transmission Gully as unaffordable, preferring to upgrade the existing coastal route, but changed its position after public consultation.
Transport Minister Steven Joyce
Steven Joyce
Steven Leonard Joyce is a New Zealand politician, who entered the New Zealand House of Representatives in 2008 as a member of the New Zealand National Party...
announced government commitment to the project on 15 December 2009, with a project cost of NZ$1.025 billion. The project has yet to be finally approved, but construction is expected to start in September 2014 and be "substantially completed" in 2020.
Controversy
The Transmission Gully Motorway is controversial, and has been a topic of considerable debate in Wellington politics for some time.Supporters claim that it will improve access to Wellington City
Wellington City
Wellington City Council is a territorial authority in the Wellington region of New Zealand. Wellington city extends as far north as Linden, and includes the rural areas of Makara and Ohariu. It is New Zealand's third-largest city, behind Auckland and Christchurch.Wellington attained city status in...
, arguing that the existing coastal route is too congested, is accident-prone, and could be damaged in a serious earthquake. Peter Dunne
Peter Dunne
Peter Dunne is a New Zealand politician and Member of Parliament who leads the United Future political party. He has served as a Cabinet minister in governments dominated by the centre-left Labour Party as well as by the centre-right National Party...
, MP for Ohariu-Belmont, says that "[i]mproving Wellington City's northern access and egress is a vital key to the future economic performance and prosperity of the whole region, and the Transmission Gully highway is a vital link in that chain".
Opponents of Transmission Gully state that there are better ways to improve access to Wellington. The fact that such a highway would require an extremely steep gradient on its northern-most end and would thus not actually offer any improvement over the existing coastal highway has been recognized by most opponents. The route that the highway must take is along the major fault line of the region, which would make it at least as earthquake prone as the existing coastal highway.
Some suggest that the existing coastal route should be upgraded, rather than building a completely new route. This was the original recommendation of the Regional Council, and was put forward as the primary alternative to building Transmission Gully. Public submissions to the Council were in favour of Transmission Gully, and the Council has changed its stance in response.
Opponents of upgrading the coastal route say that doing so would cause significant disruption to the communities it passes through, whereas Transmission Gully avoids urban areas. The former Mayor of Porirua, Jenny Brash
Jenny Brash
Jennifer Sylvia Brash, QSO , known as Jenny Brash, is a former Mayor of Porirua City, Wellington Region, New Zealand. Prior to being Mayor in 1998–2010, she served nine years as a City Councillor...
, has said that an upgrade would generate large numbers of complaints from Porirua residents, and would therefore have difficulty receiving resource consent.
Others, such as the Green Party
Green Party of Aotearoa New Zealand
The Green Party of Aotearoa New Zealand is a political party that has seats in the New Zealand parliament. It focuses firstly on environmentalism, arguing that all other aspects of humanity will cease to be of concern if there is no environment to sustain it...
and the lobby group Option 3, believe that the money would be better spent on improving Wellington's public transport
Public transport in Wellington
Public transport in Wellington, the capital of New Zealand, is well developed compared to other parts of the country. The system covers the Greater Wellington region, including Wellington city, Lower Hutt, Upper Hutt, Porirua, the Kapiti Coast and the Wairarapa.-Administration:Public transport in...
, particularly the existing rail line. They argue that the original choice between building Transmission Gully or upgrading the coastal route was a false dichotomy, and that in reality neither option is necessary or desirable.
Cost
Some opponents of the Transmission Gully project believe that its overall cost is too high, and that the region has insufficient funds to spend on it, with a benefit/cost ratio of 0.6. The previous Mayor of Wellington, Kerry PrendergastKerry Prendergast
Kerry Leigh Prendergast, CNZM was the 33rd Mayor of Wellington . She was the second woman to serve as Mayor of Wellington, succeeding Mark Blumsky.-Before politics:...
, has described the project as "unaffordable". It has been suggested that making Transmission Gully a toll road
Toll road
A toll road is a privately or publicly built road for which a driver pays a toll for use. Structures for which tolls are charged include toll bridges and toll tunnels. Non-toll roads are financed using other sources of revenue, most typically fuel tax or general tax funds...
would help resolve this problem, although no decision has yet been taken on the matter, and tolls would only cover a fraction of the funds necessary to build the highway.