The temporary venue, which will be easily distinguishable by its silver wrap and an inflatable roof made from recyclable plastic, will be built by a raft of firms from across the UK, including the ES Group
They were forced to move as part of the relocation of businesses following the awarding of the Games to London, but will now build the main structure of the 5,000-seat venue.
The ES Group specialise in building stages and support structures for major events, including the 2010 Ryder Cup at Celtic Manor.
They will be joined by Ipswich-based Jackson Civil Engineering Group Ltd, who are doing the substructure works; Alto Seating Systems Ltd in Redditch, who will construct the seating; A&T/ Barr & Wray (Glasgow), who are installing the temporary pools, and the Byrne Group Plcin Teddington, who are undertaking the general building work.
The design team, led by David Morley Architects, also includes Buro Happold and Max Fordham, and Balfour Beatty Engineering Services Ltd is doing the mechanical and electrical work.
The ground is currently being prepared before work starts on the substructure in early March.
The wedge-shaped Arena, which rises from 12 metres to 25 metres, will contain a 37 metre-long competition pool and a warm-up pool.
It will stage·the·men's and women's water polo competition during the Olympics.
After the Games, the venue will be taken down, with elements reused elsewhere in the UK, including·incorporating materials available through the rental market to promote reuse and reduce construction waste.
Ian Crockford, the ODA Project Sponsor for the Water Polo Arena, said: "The start of work on the Water Polo Arena, one of the last venues to be built on the Olympic Park, shows how far we have come since construction started in 2008.
"The venue will join the Aquatics Centre to form a dramatic and action-packed gateway to the Olympic Park when spectators arrive in 2012."
The venue will be built at the main eastern entrance to the Olympic Parknext to the Aquatics Centre, in what will be one of the most compact areas of the 500-acre site.
To·make the best use of available space, a number of back of house facilities will be shared between the two buildings.
Spectators will be able to access the internal concourse level with step-free access via a series of accessible ramps.
The contractors and suppliers were appointed to deliver the Arena through the existing ODA managed package frameworks set up to efficiently deliver a range of temporary and smaller permanent venues.
October 2010: London 2012 appoints water polo and diving managers