The Towers are a series of 19 pylons, each 30 metres tall, which unite many functions on a very small footprint to facilitate crown flows. Large-scale photovoltaic solar collection is couples with sophisticated lighting and structure to create functional public sculpture. At their base, the Towers house all the services required to events in the Plaza, including high and low voltage power, communications, water and drainage.

A five metre square facetted mirror, designed with Barry Webb and Associates, has sophisticated photo metrics, which reflect area lighting indirectly onto the Plaza, providing a unique, glare-free night time ambience. 1150 square metres of photovoltaic collectors are arranged 6 metres above the paving, to provide areas of shade in the Plaza at key locations. These dramatic floating louvred shades are self-coloured and have been designed to provide easy event and maintenance access. At the time of completion the photovoltaic provided one of the largest public solar collectors in the world, and continue to generate a net surplus of power.

The Towers have precast concrete bases, providing volumes to house services and seating. The shafts are angled to true north, away from the large masses of the stadia and towards the Olympic Boulevard, uniting the separate Towers into a cohesive group.

The Arboretum is a collection of 100 forests, each home to a single internationally-endangered species. The species are chosen from the many thousands that are threatened world-wide, and curated according to colour of foliage, pattern of bark and leaf, filigree of branches, scent and texture, and suitability to the local growth conditions.

A simple formal geometry, developed from Griffin’s water axis, interacts with the landform on which it is laid. 250m wide forest bands are defined by native-planted clearings leading to the lake. Each Forest offers an immersive experience of a single species, a hermetic world which kindles the pleasure of being enveloped in a consistent world. Each Forest holds a viable population, creating a seed bank for each species’ native land, so that vulnerable and endangered species are preserved.

Defined gardens and event spaces are surrounded by the forests. With the provision of services, pavilion shelters and toilets these spaces have the potential to be booked for a wide range of events, as well as providing opportunities for themed gardens, sponsored plantings and temporary exhibits, performances, artworks and garden designs. The 1400m long Central Valley forms a focal clearing at the centre of the site, with a sculpted series of terraces linked by a cascading stream and a fully-accessible pathway.

The linear water feature feeds as the main water storage facility, located at the foot of the Central Valley the Arboretum. The dam and other water tanks will have a total capacity of 20 megalitres of recycled water, and will be a demonstration of water sensitive landscape design, showcasing contemporary design and ecological water recycling technology.

By the planned opening of the Arboretum to commemorate Canberra’s centenary in 2013, all 100 forests will be planted, complemented by a major Visitor Centre, the Event Terrace, a regional Playground and the first of the many gardens planned for the site. A full road and pedestrian circulation system will be operational, and a site-wide interpretation strategy will underline the projects long-term ecological benefits.

The project was designed to be experienced at a freeway speed of 110km per hour. It includes three series of sculptural sound walls, a pedestrian bridge and a set of design parameters for road bridges, crash barriers and retaining structures.

The main series of walls by Tonkin Zulaikha Greer total over 2 kilometres in length, and are made from facetted austenitic steel sheets modelled in simple concave and convex folds to produce a gently undulating wave of steel floating on a recessed dark concrete base.

A second series of walls by Taylor Cullity Lethlean, are translucent and transparent, preserving light and views from residential areas. These are edge-lit acrylic, sandblasted with a digital pattern and overlaid with coloured precast concrete blades. The third series, by Tonkin Zulaikha Greer, build on the existing landform with dramatic earth sculpting. The use of gabions and heavily planted earth berms achieve the required sound control.

A major element of the work was a new pedestrian bridge, which was designed as a gateway to the distant city of Melbourne, visible on the horizon. The bridge, a complex curve in plan and elevation, is a tubular steel truss faced with the same austenitic steel as the main sound walls, which at this point appear to leap over the road in a gesture of welcome or farewell.