Medlow Bathers have welcomed work on long-sought turning lanes into two of its residential streets but are concerned that the design won't help those trying to turn right on to the highway.
Transport for NSW has begun clearing trees to provide dedicated left- and right-turn lanes into Bellevue Crescent and Foy Avenue on the western side of town.
But there are no plans for a protected turning bay for those trying to turn right out of Bellevue Crescent, heading towards Katoomba.
Resident Jennifer Tierney recently wrote to the minister for regional transport and roads, Paul Toole.
She said the design of the upgrade at Bellevue Crescent, with no turning bay to allow people heading east to drive halfway across the highway while waiting for traffic to clear, meant "risks remain high".
"There are 70+ houses in the Bellevue Crescent/Delmonte Ave area, most permanently occupied," she wrote. "TfNSW's incomplete safety upgrade means residents continue to face the everyday danger of turning right out of Bellevue Crescent.
"By TFNSW acknowledging the need for an urgent intersection safety upgrade, TfNSW acknowledges the intersection is not safe."
She said it was almost inevitable that there will be accidents and urged a rethink of the design, saying it was "not too late".
She stressed that the residents didn't want any complicated engineering, merely a painted-on lane that would offer protection for cars trying to make the right-hand turn.
Such a lane exists at many points on the highway, including nearby Explorers Road and at Scott Avenue in Leura.
Vera Hartley, who lives on the western side, said she was "taking more and more risks because I just can't get out".
She also believed the size of the Bellevue Crescent sign was a problem, with many thinking residents were indicating to turn in to the United service station nearby.
"How much money would it cost for a big sign so people know there's a street here," she asked.
Fellow resident, Andrew Ford, said: "This is meant to be a safety upgrade but it won't be."
