The Olympic Delivery Authority (ODA) has awarded the construction contract for the Eton Manor Olympic venue to Mansell Construction Services.
ODA said this was the last contract to be awarded for the Olympic Park venues, which have three main phases – Olympic, Paralympic and legacy.
The venue will house three Olympic-size swimming pools, one synchronised swimming pool and one water polo pool to be used for athlete training during the games.
Eton Manor will host the wheelchair tennis event during the Paralympic Games.
The 10,500-seat arena will be transformed into first-class sports and leisure facilities for the games' legacy, and will be managed by the Lee Valley Regional Park Authority.
The facilities will include a hockey centre with two competition pitches, permanent and temporary seating, a tennis centre with four indoor and six outdoor courts, and five-a-side football pitches.
Initial earthworks and construction of the main sporting facilities will begin later this year.
The central building will have a brown roof, and the design will develop ways to conserve energy and water.
The ODA will also build two new land bridges to link Eton Manor with the surrounding area.