Community integration rather than showy design will be the legacy of London 2012

While summer 2012 is the date imprinted on the minds of the Olympic organisers, the London Legacy Development Corporation (LLDC) is working to a rather different timetable. Spring 2014 is its target for the reopening of the whole of the site into a new park for London, with some parts open from next summer.

The venue design may have been getting all the attention, but the crucial though less trumpeted £1 billion of infrastructure has required every bit as much thought.

This includes 33 bridges, 9km of roads and utilities provision — all facilitating the viability of the site post-Games, along with £292 million of legacy transformation work.
“Legacy has led the design from the beginning. Seventy-five pence in every £1 has gone on legacy,” says David Baird, infrastructure project sponsor at the Olympic Delivery Authority (ODA).

“It’s not the glory stuff but it’s crucial to making the site work,” says former ODA principal design adviser Kay Hughes of the infrastructure.

That approach is shared at the LLDC, which will take custody of the site in October and begin its 18-month Clear, Connect, Complete programme to turn the site into the Queen Elizabeth Olympic Park, stripping away temporary venues and tailoring the area to the very different needs of legacy. The result will be a 102ha landscaped park, wilder in character in the north and more urban in the south, with key new public spaces at each end.

“It’s been developed so that everything sits beautifully in its environment. We’re connecting the park to the neighbourhood with new roads, cycleways, paths and bridges, and each of these is being carefully designed to enhance the public realm and bring areas back into public use,” says Colin Naish, executive director of infrastructure at the LLDC.

The many new bridges may not have the visual impact of the new utilities structures, but they are nonetheless crucial to connectivity into and through the park.

Most of these relatively modest structures have been designed by Allies & Morrison, which has provided consistent design input to the project for five years, contributing to Edaw’s original masterplan then working as design architect for structures, bridges and highways for the park for the ODA and the LLDC. With its inherited network of waterways, the proximity of adjacent rail and dual carriageways, not to mention electricity pylons, contaminated land and Japanese knotweed, the site was “very congested and tricky,” says Allies & Morrison director Simon Fraser.

Due to their frequency and quantity it was decided early on that the bridges should not be landmark objects in their own rights but should instead be deliberately simple, and well integrated into the landscape and adjacent concourse.

The bridges, which vary in width from 4-60m, have geometric box-girder structures that carry utilities infrastructure beneath the steel deck. Common geometries were applied to concrete deck-edge beams, abutments and wing walls, enabling a standardisation of details and quality. Parapets run off into landscape, blurring definition of bridge and landscape.

A range of retaining walls includes gabions filled with crushed concrete from the site construction. “It was important to get a consistent language,” says Fraser. “We developed a strategy for a family of bridges that sat below the concourse level to carry the landscape from one side of the waterway to the other. “The most critical interface was with the landscape,” he adds.

A key consideration was how to deal with the conflicting footfalls of Games and legacy. Not wanting to leave unnecessarily wide structures, Allies & Morrison designed nine temporary bridges, which will be removed after the games to reveal pre-designed terraces.

The two Heneghan Peng-designed Central Park bridges will undergo the greatest transformation.

For the Games, the z-shaped structure has been filled in with colourful temporary decking to create a 60m-wide crossing. Afterwards, this will be removed to leave just a 4m-wide link between the permanent structures.

Undersides of the pedestrian bridges on the site are colour-coded according to the waterway they cross. Further variety is provided by an overlay of artistic engagement on several of the bridges, including work by artists Martin Richman and Jason Bruges Studio.

It has been developed so everything sits beautifully in its environment

As well as pedestrian flow around the park, “stitching” the site back into the surrounding area is another key focus.

This includes reinstating links with Hackney East Marshes to the north where a landform created to provide the appropriate gradient for wheelchair access to the site will in legacy mode become a terrace with mountain-bike trails and informal seating overlooking the marshes.

In the south, connections will be introduced into the adjacent Carpenters Road estate. In the west, two bridges for legacy use have already been installed over the River Lea.
“The pedestrian bridges and landscape is stunning,” says ODA’s Baird, confident that visitors will be impressed.

Allies & Morrison’s Fraser anticipates exploring the park in legacy mode will help reconnect local residents with the waterways. He is comfortable that the infrastructure that has been so carefully planned to make this happen will largely go unnoticed by visitors.

“I think that’s OK. Certain things they’ll spot, others will just pass them by and that’s exactly right.”