A bridge designed to be “floodproof” has gone almost completely under water as residents in Windsor wait anxiously while the worst flooding event in almost 50 years wreaks havoc in the area.
The Bureau of Meteorology has warned residents could experience the worst flooding event in northwest Sydney since November 1961.
Floodwaters are expected to rise to crisis levels at Windsor, Pitt Town, North Richmond, Freemans Reach and Colo.
Penrith and other towns and suburbs along the Nepean were ordered to evacuate on Sunday as NSW battles devastating floods following almost a week of severe rain.
The Hawkesbury River region is bracing for flooding that could leave residents with disrupted utilities for months.
On Monday, locals watched on as the Windsor bridge, built last year, went under water following its closure on Sunday.
The NSW government said the new bridge would be better able to cope with the impacts of flooding.
The deck is three metres higher at the northern bank and six metres higher at the southern bank than the old bridge.
However, the approach to the bridge on the Thompson Square side is not higher than the ground-floor levels of nearby buildings.
An SES spokeswoman said major flooding remained around the Windsor area including North Richmond, Lower Portland and suburbs surrounding the Hawkesbury-Nepean catchment.
She said there were about 150 jobs in the area, 70 of which were flood rescues.
NSW Emergency Services Minister David Elliott said the Australian Defence Force was being called in to help.
He said specialist personnel were expected to arrive in the next 24 hours as fears rose for communities on the mid-north coast, the Hawkesbury valley and western NSW.
More than 150 schools are closed across the state.
“They will be using whatever assets they have available,” Mr Elliott told Sky News.
He said the ADF would be more be more involved with helping with the clean-up once the flooding was over.