Fifteen new flood rescue boats for the NSW State Emergency Service (SES) were assembled by Kurnell company, Britton Maritime Systems.
The firm, which was established in 1987, specialises in vessels for emergency services and the military, as well as commercial craft.
A demonstration of the flood rescue boats was carried out in Botany Bay on Monday by SES volunteers from Sydney Southern Region.
Observers included Emergency Services Minister David Elliott and Environment Minister and Cronulla MP Mark Speakman.
The vessels cost the state government $845,575.
Mr Speakman said he was pleased the government had supported local manufacturing, by having Britton Marine assemble the boats.
The custom-built vessels can carry large quantities of food and water to help resupply stranded communities, and hold quad bikes so farmers can muster stock in flood-isolated areas.
They fit intensive care stretchers to help evacuate hospital and aged care facilities, are equipped with GPS systems and have aluminum propellers to protect from debris in the water.
SES assistant commissioner Julie Hately said volunteers had carried out 263 flood rescues across NSW in the last 12 months.
New vessels would be distributed to units in Aberdeen, Mount Druitt, Armidale, Hawkesbury, Lithgow and Lake Macquarie, she said.