On weekends, the proportion of Trulia's mobile users swells to as much as a third of overall traffic, Mr. Flint said.

WSJ: Trulia Soars 41% in Debut

The report said that traffic at the busiest time of the day could increase by 14% and the proportion of vehicles taking more than seven minutes to travel through the four villages would more than double.

BBC: Suffolk County Council report calls for villages bypass