Roads and Maritime Services (RMS) has declared a navigation restriction area about 700 metres downstream from the Frederickton township for safety reasons.
RMS Maritime Acting North Coast Manager Stephen Brown said work to build new bridge piers in the Macleay River, which started this week, would continue until early November, weather permitting.
“The new bridge over the Macleay River will form part of the Kempsey Bypass,” Mr Brown said.
“Work will take place between 7am and 6pm daily.
“The area will be bounded by a silt curtain and yellow buoys and lights at night.
“A navigation channel has been created between two piers near the southern bank of the river and is indicated by port (red) and starboard (green) buoys on approach to the work area.”
Mr Brown said a temporary rock platform had already been built to assist with the building of the piers.
He said for safety reasons, skippers should travel at a maximum speed of 4 knots within 100 metres of the work site, keep a proper lookout and keep vessel wash to a minimum.