The River Wyre burst its banks during high tide at Skippool Creek this afternoon.
Following heavy rain this morning, the river spilled over into Wyre Road, off Skippool Road near Thornton.
Water levels had not reached nearby homes and businesses at around 1pm, though they were rising.
Nearby Underbank Road, where a flood alert was in place overnight, was also under water.
A Wyre Council spokeswoman said the roads suffered "tidal flooding" rather than as a direct result of the rain. Workers from the authority were dispatched to assess the situation.
Some residents in the area had taken precautions to protect their properties, with sandbags spotted in a number of gardens off Skippool Road.
A flood alert remains in place across much of the low-lying land in Wyre until 2am tomorrow (Wednesday).
The areas listed are: Fleetwood Docks and Marina, Fleetwood Marsh Nature Park, Barnaby's Sands, Burn Naze, Sower Carr, Hambleton, Stannah, Trunnah, Thornton, Skippool and Little Eccleston.
The "main areas affected" could be Hambleton and Thornton, the alert added.
"We are closely monitoring the situation," the Environment Agency said. "Please avoid using low-lying footpaths near local watercourses."
Wyre Council said earlier it wanted to hear from those who suffered flooding in their home - but not garden - so it could "collate records and improve our response to future floods".
Call (01253) 891000.