India, March 16 -- In the heart of Mahalaxmi, the jagged concrete skyline casts a dark shadow over something so quintessentially Mumbai that losing it would mean losing a little of the city itself.

This is Mumbai's largest open-air laundromat, or Dhobi Ghat, where 730 dhobis or washermen hold historical rights - and licences - to wash and dry clothes and linen for a living. The land, owned by the Brihanmumbai Municipal Corporation (BMC), houses a grid of 730 'washing stones', or concrete cubicles. It also includes a large drying area, where each dhobi has been allotted space for two ropes to hang their laundry. Or so it had been for more than a century.

The livelihood of these 730 dhobis, and hundreds of others engaged at the ghat, is a...