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2020 / 2021 Edition

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Into The Final Lap

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Long after the laps of sporting glory have faded from memory, judgements about the success of London 2012 will be based on how well its sustainability goals have been achieved. For the Olympic Delivery Authority (ODA), the public body charged with developing the venues and infrastructure for the 30th Olympiad and ensuring their legacy, sustainable construction methods have been a priority. Quarry Management takes a look at the aggregates-hungry project as it enters the final lap of the construction phase

The Environment and its fresh-faced teammate Legacy are relatively new to the scorecard of the Olympic Games. They certainly did not line up beside Sport and Culture at the very first Games 2,800 years ago, nor even at their revival in 1896. But today Sustainability is a big part of the Olympic movement and green takes its place on the podium alongside gold, silver and bronze.

It was the International Olympic Committee (IOC) that introduced the Sustainability requirement. Its 2005 mission statement declared that a successful Olympics should have ‘environmental protection’ and, more importantly, ‘sustainability’ as prime elements of its planning and operation. It added that ‘positive legacies’, ie rewards that last well beyond the three-week sports-fest, was another essential outcome.

Sustaining the buzzword

Given the prominence of sustainability issues in global politics and repeated criticism of the Olympics for their environmental impact, it was inevitable that the IOC would eventually turn to greening the Games.

A level of environmental assessment was first demanded following the 1992 Winter Games in Albertville, France, where insensitive venue construction caused significant damage to vulnerable alpine ecosystems. But the notion of Legacy did not win its place in the Olympic Charter until after the Greek tragedy of the 2004 Summer Games.

Played out in the shadow of the Acropolis, the Athens Games cost £9 billion (the same budget as the London Games) and were successful from a sporting perspective. But seven years on, 21 of its 22 purpose-built venues lie derelict and abandoned and the country is thought to be paying some £500 million a year for security and maintenance of the sites.

China did a lot better. Despite a widespread perception that the massive Beijing Olympics of 2008 were neither environmentally friendly nor sustainable, even Greenpeace accepts that the Games created a positive legacy for the city, and saved 1.2–1.5 million tonnes of CO2 through energy-conservation projects and renewable energy.

However, China did not achieve all of its targets. It fell down by not insisting on environmentally friendly policies for procurement and construction, not pursuing a zero-waste policy, and not introducing an internationally recognizable system of timber procurement – such as the Forest Stewardship Council (FSC) standard – for construction materials.

Regenerating the East End

All these areas have been addressed for London 2012 and the goals of the Olympic Delivery Authority (ODA) are focused on regeneration. Besides injecting sustainable thinking into every aspect of the Games, from venue design and location to event management, the long-term aim is to transform a 500-acre plot of derelict land in a congested and deprived area of high unemployment into a vast urban park.

In the process, it aims to demonstrate how mega-cities can effectively deal with environmental and social challenges.

It is an ambitious plan. This part of London’s East End includes Stratford and the Lea Valley, and has long been overlooked.

During the Industrial Revolution it was the centre of some of London’s most unappealing industries; home to chemical plants and factories producing soap, matches and ink. It was devastated by WWII bombs and the closure of the nearby Royal Docks, and has virtually no cultural or must-visit attractions. In its recent state it was highly unlikely to ever win a place on the tourist trail; long-term neglect of its many waterways had resulted in poor water quality and, not to put too fine a point on it, a bit of a whiff.

Ironically, although it had been carved up by railway lines, it has always been poorly connected to the rest of the capital. Or to anywhere else for that matter.

The big clean-up

Delivering one of the UK’s most complex and greenest clean-up operations on time and on budget was to be one of the ODA’s early achievements.

More than 52 pylons marched across the landscape and had to be dismantled. More than 200 buildings, including two 12-storey accommodation blocks once used by students at the University of East London, were demolished. Soil contaminants included oil, petrol, tar, cyanide and lead, and some very low-level radioactive material. Some 30,000 tonnes of silt, gravel and rubble were removed from the rivers and canals, plus countless tyres and shopping trolleys and even an occasional car.

In total, nearly 3 million cubic metres of earth were moved on the Park and more than 91 million litres of contaminated groundwater were treated using innovative techniques. These included: pumping out and treating water containing oil and ammonia; injecting compounds into the ground that generate oxygen, which, in turn, breaks down harmful chemicals; and controlling the movement of groundwater to prevent contamination entering the local waterways.

An area equivalent to 10 football fields was cleared of invasive Japanese knotweed and more than 5km of riverbanks were refurbished.

Six million man-hours were worked on this phase of the project.

Recycling commitments

The three-year clean-up project used sustainable techniques to recycle and reuse 97% of the demolition material (exceeding the high target of 90%), and 999,000m³ of contaminated soil was treated and reused thanks to soil washing and bioremediation. At its peak five soil-washing machines worked on site, significantly reducing lorry journeys in the local area as only a minimal amount of contaminated material, such as asbestos, and the filter cake from the soil treatment plants was taken to landfill.

An area that received special attention was a 100-year-old tip under the plot where the Velodrome has since emerged. A 35-tonne recycling machine was commissioned to sift and sort this 70,000m3 mass of old rubbish into piles of glass, metal, concrete, soil and other materials.

All recyclable materials from the demolition or excavations were recorded in a materials register. This gave designers a breakdown of the separated and stockpiled materials available for reuse in the design of venues, landscaping, bridges, footpaths and other elements of the Olympic Park.

As a result, the 2,500m2 Main Press Centre has a brown roof which uses seeds and timber logs reclaimed from the clean-up operation and is now encouraging wildlife.

Similarly, the redesign of The Greenway (a track that crossed the site) has transformed it into a key walking and cycling route using salvaged bricks, paving cobbles, manhole covers, timber sleepers and tiles.

Other recycled materials from off site also make an appearance in several of the venues. The distinctive cladding of the Handball Arena, for example, is made from recycled copper that has been aged and treated, while the truss of the main Olympic Stadium is created from reclaimed gas pipes.

But some of the venues in the Olympic Park are merely temporary and they have been designed with ‘recyclability’ in mind. The 12,000-seat Basketball Arena is a good example. It will be one of the most heavily used venues, with competition events taking place every day during the Games, watched by half a million spectators. Despite this heavy usage, and its size, the giant frame was erected in less than three months during Spring 2010.

This frame has been covered with a fabric that will form the canvas for spectacular light shows during the Games. Different contractors have been employed to construct each element of the venue, such as its frame, seating and modular accommodation. These parts are owned by the respective contractors who will dismantle, take away and reuse or recycle all the parts after the event is finished. Some two-thirds can be reused.

Similarly, the Water Polo Arena will have only a short lifespan. Work on the substructure started in March on what will be one of the last venues to be built on the Park and one of the first to be taken down again after the Games.

The temporary 5,000-seat venue will be wrapped in a distinctive silver membrane and its sloping roof will be made from air-inflated, recyclable, phthalate-free PVC cushions, which will provide extra insulation and reduce condensation.

This, and many of the other materials incorporated in the design, will be reused elsewhere in the UK after its short spell in the limelight.

Even the Park’s iconic Aquatics Centre, which is destined to become a much-needed facility for the local community post 2012, has two temporary ‘wings’. These increase the capacity of the venue from its permanent level of 2,500 to 17,500 during the Games.

In addition to reusing materials found on site, and taking a very literal approach to the word ‘temporary’, the ODA set a target of 25% recycled aggregates for the entire site. Aggregate Industries, who won the contract to become sole provider of sand, gravel, crushed stone and recycled fill materials for the venues and infrastructure of the Olympic Park, have supported the ODA in this objective.

Rail in/water out

The ODA also set a target for 50% of construction materials to be delivered by sustainable transport. This target has also been surpassed by Aggregate Industries, who have delivered significantly more than 50% of materials by rail alone.

Freight is delivered to the purpose-built Bow East Logistics Centre, which opened in June 2008. At the height of the Park’s construction phase, the 28-acre facility was managing the daily movement of thousands of tonnes of bulk aggregate products for cement production and up to 5,000 tonnes of fill material, concrete blocks and waste. Six to eight trains were running each day.

The make-up of the materials has changed as the months have passed. Instead of raw materials for cement production, precision-cut tiles for the Aquatics Centre started to arrive at the end of last year, and sanitaryware for all the venues has been on the manifests more recently.

The ODA estimates that 4 million tonnes of goods will have been moved by rail by the time the opening ceremony begins on 27 July 2012, saving 120,000 tonnes of carbon dioxide that would have resulted from an equivalent delivery operation by lorry transport.

With raw materials arriving by rail, the original preferred route for waste was along the Bow Back Rivers which connect with the river Lee Navigation and the river Thames.

This 5.5km system of canals weaves around the Olympic Park and in its late-Victorian heyday carried 2 million tonnes of material a year. After falling into disuse in the mid-20th century with the decline in both canal freight and waterside industries, the network had become heavily polluted and virtually unnavigable.

Regenerating this network will obviously play a large part in achieving the ODA’s legacy goals. In the shorter term, however, the network had a job to do: allowing freight barges to transport construction materials in, and carry waste out.

The first step was taken in March 2007 when construction of a new £23 million lock and water control centre started. It opened to barge freight in June 2009 and is known as  Three Mills Lock. It allows access for up to two 350-tonne barges for 4–6h a day, depending on the Thames tide.

Barges such as the Ursula Catherine, operated by Bennetts Barges, are loaded at a newly constructed temporary wharf near the Aquatics Centre and have been removing nine 20ft containers of waste per week. The containers are transported to a specialist recycling centre in Rainham, Essex.

Some construction materials have also made their way to the Park by water.

Long-term legacy for locals

While most reports of London 2012’s preparations have concentrated on either sustainable building methods and materials or the construction of sporting venues, the longer-term social sustainability of the project has received relatively little press.

But while the headlines may have focused on the White Water Centre (the first purpose-built venue to be handed over outside the Park), the Velodrome (the first purpose-built venue to be handed over inside the Park), and the iconic duo of the Aquatics Centre and Orbit Tower, less-exciting developments are forging ahead towards completion. These projects have nothing to do with watching people showing off their athletic prowess, but have everything to do with the much longer-lasting impact on the regeneration of the local area.

The Olympic Village, for example, has been structurally complete and clad since earlier this year. Some 6,000 of the Park’s 12,000 construction workers were dedicated to it at the peak of the build programme.

Comprising 62 residential blocks, it will be home to a temporary population of 17,000 athletes and officials during the Games. This level of accommodation will be achieved using temporary partitions which will be removed after the Games to reveal the final living spaces and bedrooms. Kitchens will then be installed and the Village will be transformed into 2,818 one-, two-, three- and four-bedroom properties.

Nearly 50% of these properties have been purchased by a social landlord consortium to become legacy affordable housing. The remainder will be sold off as private homes.

This new community will have access to a new education academy and state-of-the-art Polyclinic. Both are in advanced stages of construction and will serve as operations and medical centres, respectively, during the Games, before taking on their permanent roles for locals.

Vastly improved traffic links are another of the long-term regeneration aims now taking shape. In addition to the £125 million extension of Stratford mainline station, three new stations will link the area for the first time to the Docklands Light Railway network, providing efficient public transport into the City of London, the East End, and to Greenwich and Woolwich on the south bank of the Thames.

These public transport links will also help fulfil the ODA’s goal for 100% of spectators to arrive at the Park by public transport or by walking or cycling.

Stopwatches at the ready

The Athletes’ Village and the Park’s new public transport links will be ready in early 2012. Between now and then a series of completions will be announced.

The construction of all the permanent venues – the Olympics Stadium, Aquatics Centre, Handball Arena and the International Broadcasting Centre – is due for completion by 27 July 2011, exactly one year in advance of the Olympic torch bursting into flame.

They will join the Velodrome, the Basketball Arena, the Hockey Arenas, Waterpolo, the Lea Valley White Water Course, and the Weymouth Bay and Portland Harbour sailing facilities on the completed-venues line-up.

Fitting-out of the Athletes’ Village is due to finish in the autumn and construction work to upgrade both Eton Dorney (rowing) and the Royal Artillery Barracks (shooting) is on track for completion in spring 2012. By then all the temporary facilities at the Olympic Park will also have been handed over.

As the final lap approaches, sustainable construction methods are the only part of the ODA’s remit that can even begin to be measured. The economic sustainability of the London Games will not be known for some years. Neither will the social sustainability.

But there can be no doubt that the venues and infrastructure now being unveiled at the Park have achieved, and frequently exceeded, most of the very ambitious sustainability goals set.

Pushing the pedal for sustainable construction

Following their success in Beijing, British cyclists have high hopes for London 2012, and the Velodrome will give them the best possible stage on which to pedal for gold

Renowned track designer Ron Webb has created what is being heralded as the world’s fastest Velodrome. Whether or not records are broken next summer, the venue itself has already received acclamation as an exceptional example of sustainable design and construction.

Reflecting the efficient design of a bicycle, the building has many energy-efficient features. Its compact design minimizes the energy consumed to heat the main arena, while water-saving fittings and the harvesting and reuse of rainwater help to reduce mains water consumption by 70%.

Daylight streams in through strategically positioned roof lights to reduce the need for artificial lighting, and almost 100% natural ventilation is achieved through openings in the external timber cladding. The latter is made up of 5,000m2 of western red cedar, which, like all timber supplied to the Park, is certified by the Forest Stewardship Council (FSC)/Programme for the Endorsement of  Forest Certification (PEFC) – the first project to be jointly certified.

But it is the lightweight roof, which can move 500mm under the most extreme weather conditions, that grabs most of the sustainability headlines. Created from 16km of cable net (the type used for ski lifts), the 12,000m2 roof weighs less than half that of the Beijing Velodrome at just 30kg/m2.

Internally, Aggregate Industries supplied the precast concrete terracing units which provide seating for 6,000. Due to the unique shape of the cycling track, 140 different designs of unit were required, together with associated stairways and walling with greater tolerances than normal buildings to accommodate the ‘post-stressed’ roof.

The go-fast track has been made of sustainably sourced Siberian pine, which is known for its straight growing in the perma- frost of northern Russia but is also a very malleable and extremely strong wood. It was weathered inside the venue for months to get it acclimatized to the conditions before being laid to 1mm tolerances by a team of 26 carpenters in just eight weeks. The 250m track, with 56km of surface timber fixed by more than 300,000 nails, should last 30 to 40 years.

With its track design, a constant internal temperature of 28°C and still conditions, the Velodrome should see outstanding sports performances. Spectators will play their part, too. Research has shown that while many racing venues restrict spectators to the straight section of the track, cyclists respond better and faster to continuous crowd noise. The geometry of the London Velodrome was heavily influenced by this research, lending the venue its distinctive ‘Pringle’ crisp appearance.

Ready-mixed concrete plant exceeds expectations

With all the major venues up and approaching completion, the final whistle was blown for London Concrete’s twin ready-mixed concrete plant in January. Having produced up to 1,000m3 a day in a variety of mixes to keep contractors supplied throughout the main construction phase, its work was done.

The double installation feature had been chosen because it practically eliminated any likelihood of a stoppage halting production – a critical consideration for a project that absolutely cannot overrun.

The twin plants had been ordered and built for London Concrete prior to the contract being awarded because the company felt this would strengthen its bid. However, it was not all plain sailing; carrying out the civils works and erecting the plants in a very short timescale presented some challenges.

Almost as soon as the contract was awarded another problem arose: a previously unknown height restriction would not allow road delivery of the six cement silos to the Olympic Park. ‘Out of gauge’ loads on the railway are not easily arranged either, and at one point the company even considered commissioning a Chinook helicopter. However, even that desperate measure was not feasible and a solution was eventually found by delivering the silos to the Park’s Bow railhead and transferring them to rail wagons for their final journey.

With much less difficulty, all aggregates bound for the plant were carried by rail direct from source, including granite (primary) from Bardon Hill, Leicestershire; granite (secondary) from Melbur, Cornwall; limestone (primary) from Torr Works, Somerset; sand (primary) from Dagenham, Essex; and glass sand (recycled) from Brentford, Middlesex.

The plant, which was in production from May 2008 to November 2010, achieved the Olympic Development Agency’s sustainability targets for all concrete to contain 25% by weight of recycled aggregate and 20% by value of recycled material, as well as the target of 50% of raw materials to arrive by rail or water transport.

Light fantastic

At every Games, the Olympic Stadium is a primary focus and not just because it is at the heart of the sporting action. The building sets the tone, right from the opening ceremony, and it will be no different at the 30th Olympiad.

London 2012’s stadium will be setting out its sustainable credentials from the minute the first flag-carrying athletes appear on the track.

It is the lightest-ever Olympic Stadium, containing around 10,000 tonnes of steel – just one quarter of that used on the Beijing stadium – under a 450-tonne cable-net roof.

Approximately 6,500m³ of concrete recycled from other parts of the Park were used to create a solid platform for its construction, and its truss was made from reclaimed gas pipes.

The 450-tonne cable-net roof covers 24,500m² (equivalent to three and a half football pitches) and has a fabric covering to provide correct conditions for athletes and two-thirds of spectators.

This huge building sits on an island of 40 acres, surrounded by the restored Bow Back Rivers. Recycled granite from King George V docks was used along the riverbanks and five new bridges now connect the island to the rest of the Park.

Structurally, the stadium was completed in mid-2010. Twelve thousand precast concrete terracing units have been installed, as have 80,000 seats. Floodlighting is also in place; beaming down from 70m above the track and field are 532 individual 2kW floodlights on 14 35-tonne towers.

The internal fit-out has also been large scale, with 700 rooms and spaces, including changing rooms with showers, being completed, ready for handover.

Virtually all that remains to be done is to lay the athletics field and track. This will be carried out during the summer for optimum conditions.

The Olympic Development Authority’s sustainable development objectives

  • Minimize carbon emissions
  • Ensure efficient use of water
  • Enhance biodiversity
  • Prioritize walking, cycling and public transport
  • Reduce waste and maximize recycling
  • Create new facilities for locals
  • Use socially responsible materials
  • Meet principles of inclusive design
  • Minimize adverse impacts on land, water, noise and air quality
  • Create new employment opportunities
  • Provide for healthy lifestyles during    and after construction
  • Involve stakeholders and communities.

Finding the energy

Almost tucked away on the western fringe of the Olympic Park is the workhorse that will heat and cool the venues both during the Games and after. Hailed as the largest in the UK, the Energy Centre includes 3MW biomass boilers that use sustainable wood chips to generate low-carbon heat, and uses a Combined Cooling Heat & Power (CCHP) plant to capture the heat generated by electricity production.

The Energy Centre, together with the CCHP plant, will deliver carbon emission reductions well in excess of 1,000 tonnes per year, making a significant contribution to the Olympic Development Authority’s target of a 50% reduction across the Park.

The Centre has an initial capacity of 46.5MW of heating and 16MW of cooling through 16km of piping, which has been installed to allow future developments to link up. The building is also of flexible modular design so future technologies can be incorporated as they are developed and as demand grows after 2012. In the long term, the Energy Centre has the capacity to supply energy to 10,000 homes.

It includes five cooling towers and two hot-water boilers, each weighing around 60 tonnes.

The site-wide heat network will generate domestic hot water and heat the Aquatics Centre swimming pools and other venues and buildings.

The Energy Centre’s immediate neighbour is a new black brick built primary substation. This facility will distribute electricity across the Park and the adjacent Stratford City shopping centre through electrical networks consisting of more than 100km of cabling.

Built of materials crushed from the demolition of its original neighbour, the former Kings Yard buildings, the new substation includes a brown roof that will allow animal species to colonize naturally. The structure won the RIBA award for Commercial and Industrial Building of the Year in May 2010.

Appropriately, the substation was switched on in October 2009, making it the first Olympic Park building to be completed and ready for action.

From brownfield to green fields

One of the stars of the 2012 Games will be the 100ha of open space in the Olympic Park itself. Transformed from an ugly wasteland into a series of meadows, woods, river walks and ornamental gardens, the site will be the largest new park in Europe for 150 years.

The ornamental gardens, which stretch for half a mile between the Aquatics Centre and the Olympic Stadium on land that has been cleaned and cleared of rail sidings, contamination and Japanese knotweed, will celebrate the British tradition of collecting and cultivating plants. Interspersed with picnic lawns and timber seating, some 120,000 plants from 250 different species will be arranged into four temperate regions: Europe, Americas, Asia and the southern hemisphere.

With work on the paths and drainage completed, the planting of these riverside areas started in the new year and will be completed by the autumn. When the Games get under way, Park visitors without venue tickets will be able to watch the action on huge screens in this colourful setting.

A 45ha area of the northern park will be a quieter space. Using the latest green techniques to manage flood and rainwater in an at-risk river valley, it will provide space and habitats for hundreds of existing and rare species including kingfishers and otters.

Around 2,000 semi-mature British-grown trees – a mix of ash, alder, willow, birch, hazel, London plane, lime and poplar – and 300,000 wetland plants will be part of the Olympic legacy for this part of London. A further 2,000 trees will be planted in the Olympic Village.

Across the Park, 675 bird and bat boxes will be installed. While house sparrows have been catered for within the structure of the Pumping Station, black redstarts will enjoy around 4,000m2 of living roof installed on venues or they might opt for a box made from recycled utilities pipe placed on one of the bridge crossings to the Olympic Stadium.

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