Work on the Magnetic Island Pipeline Replacement Project is underway with sections of the 5km long structure being stockpiled at Pallarenda.

Maunsell Australia is the engineering services manager for the $5m project and Brisbane based company Canstruct won the contract to provide construction services.

NQ Water Chief Executive Officer Ken Diehm said the project is expected to take four months to complete.

"This is a very important project for residents and businesses on the island," Mr Diehm said. "The current pipeline is 20 years old and is nearing the end of its operational life."

"This work will ensure the safe and consistent delivery of water for the next 50 years."

Mr Diehm said much of the work will be concentrated in Pallarenda.

"There will be limited disruptions at two points along the beach," he said.

"The ring road will be closed for a matter of days at Terminus Park and there will be restricted access along the beach just below the park for about a week early in the project.

"There will also be ongoing restrictions along the beach at the southern end of the beach where construction will be undertaken. The beach will be closed there at regular 30 minute intervals for the duration of the project."