A new £710,000 pavilion offering a range of facilities is set to be built at Tooting Bec Lido.
The facility will include a first aid room, toilets and a fitness room for a range of activities which will be available for hire.
A joint proposal for the building has been put forward by the South London Swimming Club (SLSC) and Wandsworth Council.
There will also be a new courtyard area to provide additional space for sunbathers.
The pavilion would be created at the deep end of the Lido and will be contained entirely within the lido's existing boundaries.
Wandsworth Council have pledged £150,000 towards the scheme, while a further £311,500 is being provided by the SLSC.
A bid for the remaining £248,500 has been submitted to Sport England and a decision on funding is being expected in the new year.
It is hoped the pavilion will be open by August 2015.
Councillor Jonathan Cook, cabinet member for environment, culture and community safety said: "The lido is already widely recognised as one of the best open air pools in London, if not the country.
"This proposal, which has been drawn up with very great care to make sure it fits in with the Lido’s historic setting and the wider environment of Tooting Common, would add great value to this popular leisure destination if it gets the backing of Sport England."
The lido will re-open again next year from spring bank holiday weekend until the end of September.
It will be open 6am to 8pm until August 31 and 6am to 5pm from that date until September 30.
For more information about the lido call 020 8871 7198 or visit www.tootingbeclido.co.uk