> Working in thick sediment and almost zero visibility 15 metres (49ft) beneath the waves, divers are in a race against time to unearth the 19th-century wreck of the Dannebroge before it becomes a construction site in a new housing district being built off the Danish coast.
Crippling visibility for the divers - but it's in a harbour, just 15m of water, and a future housing district. "Cofferdam and drain" ain't cheap - but how much of that cost could be recovered in the later construction phases? Or - could they box in the site, cover the bottom with a grid of heavy plastic sheets (preventing sediment from being stirred up), and mostly clear the water with a filter system?