Of the 100 ocean pools across NSW that are hewn into the sandstone and rock shelves of our 1973-kilometre coastline, many have origin stories as buoyant as the people who swim in them.

Some like Newcastle’s Bogey Hole were hand-cut out of the rock platform by convicts in 1820, so the Commandant of Newcastle, Major James Morisset, could swim there.

Others like the Merewether and Forster ocean baths, were Depression-era public works building projects to put unemployed locals to work.

Bermagui’s Blue Pool was forged in the 1930s with labour from the local Surf Life Saving Club, and money from the NSW government as well as a colourful local, W.R. Dickinson – known as “Lord Nuffield of Bermagui” – with the aim of bringing tourists to the South Coast town.

Ocean Pools, a new book by Thames & Hudson, and an exhibition that opens this Thursday at Clovelly’s Gallery East, shines a spotlight on 70 of our state’s saltwater sanctuaries from East Ballina in the north, to Eden in the south.

Intended as a guide from the top to the bottom of the state, the book is the brainchild of Brisbane-born photographer Chris Chen and Marie-Louise McDermott – who has a PhD in the contributions of ocean pools to Australia’s surf coasts.

Chen, now based in St Peters, spent over three years photographing saltwater swimmers in their local pools.

“The pools nearest to where I live are the ones I’ve spent most time at – I love Mahon Pool (Maroubra), Giles Baths (Coogee) and Wylie’s Baths (Coogee) for their beauty and people-watching value. And of course Icebergs (Bondi) and Bronte Baths,” Chen said. “I did a number of road trips up and down the coast and I loved spending time in Newcastle at all the pools there.”