The locations of the first 50 of a £5m wave of public drinking water fountains earmarked for the capital have been announced.

The first of the new fountains – which people are encouraged to use to refill their own bottles – are being installed from this week, predominantly in tube and mainline train stations, shopping centres, markets and recreation grounds. Designed to withstand outdoor temperatures and all weathers, the fountains are attached to the mains water supply and feature a distinctive design with a giant blue “waterdrop” to make them easy to spot.

Last year plans for 20 fountains were unveiled in a ground-breaking joint venture between the mayor of London, Sadiq Khan, and partners. This was followed by an agreement with Thames Water to build on the success and install a further 100-plus facilities between spring this year and the end of 2020.

Thames Water and the mayor’s office are each contributing £2.5m to fund the venture, with the mayor’s share coming from cash earmarked for tackling the issue of single-use plastic.

Key to the new partnership is a 25-year maintenance agreement negotiated with Thames Water, Shirley Rodrigues, deputy mayor for environment and energy, told the Guardian. “What consumers told us in our work on pilots was that they wanted to be able to refill their own bottles from fountains that were safe, accessible, visible – and working,” she said. “We’re very excited about this and we are in the process of evaluating [council] bids for locations for the remaining fountains.”

Khan’s predecessor and Tory leadership hopeful, Boris Johnson – expected to become prime minister next week – announced “a new era of public fountains” in 2008 but did not follow it through.

The move comes amid growing public concern over plastic pollution in the world’s oceans. In the UK 38.5m plastic bottles are used every day; just over half of those make it to recycling, while more than 16m are put into landfill, burned, or leak into the environment and oceans. The average Londoner buys more than three plastic water bottles every week.

The Guardian has learned that retail giant John Lewis is in discussions with the metal water bottle brand S’well about a partnership that would lead to the first free water fountain being installed in one of its London stores.

Meanwhile, London’s Borough Market is to introduce a fourth water fountain as part of its aim to become the UK’s biggest entirely plastic-free food shopping destination.

The mayor’s office is also supporting a parallel drive to make free tap water accessible to consumers via the City to Sea refill app, with 2,500 restaurant chains including Leon and Costa Coffee now participating. The Refill campaign persuades businesses to sign up to a scheme allowing people to refill their water bottles on their premises rather than throw them away.

Where the new fountains will be located

Bexley

Abbey Wood Station

Belvedere Recreation Ground, Welling

High Street, Welling

Kingston

Victoria Road

Elm Road

Old London Road

Tolworth Broadway

New Malden High Street

Brent

Willesden Green tube

Lewisham

Manor House Gardens

Mayow Park

Hilly Fields

Mountsfield Park

Camden

Kentish Town Station

Russell Square

Camden High Street

Merton

Raynes Park Station

Morden Tube Station

Colliers Wood tube station

Mitcham town centre

Croydon

East Croydon Station

Norwood Junction

North End

Southwark

Potters Field Park

Brimmington Park

Dulwich Village

Nunhead Green

Ealing

Melbourne Avenue, West Ealing

Hanwell Clock Tower

Walpole Park

Wandsworth

Garratt Park, Earlsfield

Tooting Broadway Station

Balham Station

Southfields Station

Greenwich

General Gordon Square

New Eltham Station

Plumstead Station

Passey Place, Eltham High Street

Charlton Station

Additional Stations

Blackfriars

Shadwell

Crystal Palace

Brockley

Edmonton Green

Hoxton

Chingford

Enfield Town

Hackney

Broadway Market

Worship Square

Mare Street

Ridley Road Market