THE section of David Low Way which was washed out by torrential rain last month is expected to have both lanes operating next Friday.
That's the start of the Mooloolaba Triathlon weekend which generates extra traffic up and down the Coast and causes the temporary closure of the Sunshine Motorway from Maroochydore to Coolum.
Transport and Main Roads acting regional director Mark Chilton said reconstruction work to fix the collapse near the Coolum soccer fields had been pushed back by record falls in the region.
Crews had been on standby for more than a week, waiting for the site to dry so layers of earth and gravel needed around the culvert pipes could set and hold.
"Unfortunately, this area is very low lying and the culvert forms part of the main drainage structure for the Noosa National Park," Mr Chilton said.
The work involves slope stabilisation, drainage, pavement repair and replacing the collapsed culverts with larger pipes.
Currently only one lane is open under 24-hour traffic control.
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