Agenda item

This report sets out the results of the Hammersmith Flyunder Feasibility Study.

The Committee received a report and presentation on the Hammersmith Flyunder Feasibility Study. The Committee heard about the engagement undertaken by the group carrying out the Feasibility Study, which had met with neighbouring boroughs and Transport for London, held a Flyunder summit, with those in attendance completing a questionnaire, met with local stakeholders and meetings with both administration and opposition Councillors.

 

The Committee heard that the Feasibility Study showed that a tunnel was possible, and that 3 possible routes for that tunnel had been identified. The Study had identified benefits and disbenefits associated with each of those 3 options, and had examined the 4 areas identified as key concerns at the summit (traffic diversions, cost, A4 closure, construction lorries).

 

The options identified were for a short tunnel to run from Furnivall Gardens to west London College, and for a longer tunnel to run from Sutton Court Road to either North End Road or to Earls Court Road. The Study identified that, due to the volume of the traffic exiting the A4 between Chiswick and Earls Court (50%), the latter options would require either additional tunnel exits (at additional cost) or would not enable the removal of the existing structures in Hammersmith Town Centre. It was noted that the Study would not be able to make a full strategic assessment of the impact of any of the options, and that this would require TfL input.

 

The Study identified that all three options would have a similar impact in terms of traffic disruption during construction, though the disruption would occur in different places based on the option chosen. The construction time and associated disruption was of similar duration for all three options. In relation to construction traffic, the Study had identified the likely quantity of spoil to be removed, and the quantity of lorries required, with and without use of the river. Finally, the Study had estimated the cost for each option, with Option 1 estimated as £218 million, and options 2 and 3 at £1210 and 1297 million respectively.

 

The Study had also undertaken a master Planning exercise, to identify the value of the land freed for redevelopment which could support the cost of construction. Based on the assumptions set out in the report, a figure of £1 billion had been identified. The completed Feasibility Study would be sent to Transport For London, who would be asked to continue the work undertaken.

 

The Committee asked the following questions and received the following responses

 

What was the life of the existing structure and what was TfL’s position on replacement?

 

• TfL believed that the Flyover had decades of life, but had been supportive of the Study and of the idea of tunnelling in general.

 

How did local businesses feel about the potential disruption?

 

• Hammersmith BID was commissioning its own study of the economic impact, which would be included with the final Study submitted to TfL, but were excited by the idea in principle.

 

How would the proposed plans increase public open space and access to the river?

 

• The removal of the Flyover would create additional public space in the centre of Hammersmith, though enabling development would also take place.

 

Why was the use of the river for spoil not confirmed?

 

• The Study was to look at the feasibility of a tunnel, and did not contain a full construction plan, including on the use of the river for spoil.

 

What impact would tunnelling have on drainage and the water table?

 

• There should be no issue, if the tunnel was designed correctly.

 

What were the merits of Option 2 and 3?

 

• Option 1 would not allow the reconfiguration of the gyratory, and would leave the A4 in place along a significant section of the route, including Hogarth Roundabout.

When could a response from TfL be expected?

 

• The Study was a direct response to the challenge set to Boroughs by the Roads Taskforce, and TfL had been engaged with the Study Group’s work throughout. There was no firm date for decision, however.

 

Residents who had attended the meeting were then given the opportunity to comment and ask questions. The questions asked and answers given are summarised below:

 

Several residents emphasised the need for as long a tunnel as possible, and noted that the significant contributions to the urban realm and to air quality a tunnel could make should be emphasised.

 

• The Study authors said that the Council could press TfL to take full account of these issues in reaching a decision. They also noted that air quality might not benefit at tunnel exits and entrances.

 

Residents asked whether a North-South Tunnel had been investigated.

 

• Officers said that preliminary study had shown this to be prohibitively expensive and difficult, with little traffic usage. Full strategic modelling would be required to be assured of this, however.

 

Residents asked what the approximate size of a tunnel entrance would be.

 

• The Study authors said that the ramp would be approximately 200 metres in length.

 

Residents asked for clarification of the impact on residents living south of the A4.

 

• The Study authors said that this would depend on the option chosen, and the subsequent treatment of the A4.

 

Residents expressed a desire for open space and a minimum of residential development.

 

• The Study authors said that the proposal would allow for an increase in open space around St Pauls and the Apollo, with a possible increase in size of Furnival Gardens, but that development would be required to fund the development.

 

Residents asked why no option began at the Hogarth roundabout.

 

• The Study authors explained that the entrance needed to be further back to allow the tunnel to get under the roundabout, the Fullers Brewery and the river.

 

Residents asked for an estimate of the timescale for a solution, assuming one could be agreed.

 

• The Study authors suggested that while construction would be relatively quick once commenced, the governance process could be lengthy, with the Limehouse Link taking ten years to reach final approval.

 

Residents present also expressed the following concerns:

 

• Residents expressed concern at the idea that a tunnel could be used to add capacity to the network without the removal of existing roads, given the changing patterns of use.
• Residents welcomed the report, but suggested that a comprehensive solution, addressing issues such as the north-south route along with tunnelling was required from TfL.

 

The Committee welcomed the work done by the Feasibility Study, and recommended that the final version be forwarded to TfL for further action. Having noted the comments of residents in attendance, it also resolved to recommend that the Study and the Study group should place a strong emphasis on the environmental benefits and the benefits for Hammersmith Town Centre that the proposal would bring.

 

RESOLVED THAT

 

(i)            The report be referred to Cabinet, with the recommendation that they endorse the Feasibility Study and forward it to TfL, and;

(ii)           That the Study and the Study group should place a strong emphasis on the environmental benefits to residents and the restoration of community links that the project would bring, and that TfL be recommended to take full account of this in their decision-making process, and;

(iii)          That the minutes of the meeting be forwarded to Cabinet with the report.