Boaties navigating the Maketu bar and the Kaituna cut have been urged to allow more time to make a safe crossing now that dry weather has led to silt build-up.
Bay of Plenty Regional Council's Regional Harbour Master Peter Buell said locals had always operated by a basic 'rule of thumb' that if conditions were reasonable, they could still safely launch their boat at Maketu and get across the bar until two hours either side of low tide.
"There is no longer a safe time to cross near low tide, and boaties should only attempt to cross the bar within three hours either side of high tide to ensure the water is deep enough," he said.
"Any time outside of that and they risk getting caught out on the newly formed sandbar. It does mean a much shorter time limit for sailing beyond the bar."
He said the Kaituna was even more dangerous.
"Depth over the bar at Te Tumu, also known Kaituna, is primarily influenced by the volume and speed of water flowing out to sea through the mouth on the falling tide, combined with waves and long-shore sediment drift.