Crowds flocked Friday to see water begin to trickle into an artificial lake on the site of an old German steelworks, bringing new hope to a depressed smokestack city. Homes and offices are to be built around 24-hectare Lake Phoenix, and planners hope sailboats will scud over the lake on summer days, bringing a seaside sense of style to the city of Dortmund, dpa reported. The coal and steel industries have largely died out in Dortmund and neighbouring towns, leaving it an unemployment black spot. Copying schemes that have brightened up blight zones of former communist East Germany, the western city of Dortmund decided to rip down the abandoned Hermann Steel Works and remodel the 99-hectare site. Excavators dug the hole for the lake, centrepiece of the 67- million-euro (91-million-dollar) development. Since the hole is deeper than the water table round about, ground water will naturally seep into the hole over the next year, and rain will then bring the groundwater back into its natural balance. The ceremonial start of the filling was accompanied by a fireworks show and thousands of people watched the spectacle. "A dream that no one round here would have dared imagine 20 years ago is coming true," said Dortmund's mayor Ullrich Sierau. Despite the initial lack of water, a Lake Phoenix boating club has already signed up 387 members.