The barriers at Welney Wash are now closed after the river depth increased to nearly three meters overnight.
The Welney Flood Watch group posted on Facebook this morning (February 19) that the water depth at 6.30am was four inches.
Some traffic was still travelling through, but the page warned that "50 per cent is turning around".
The post read: "Good morning all, barriers are now across the bridge at Welney this morning.
"Water depth on the road as at 6.30am this morning and as displayed by the flashing signs is 4inches /12 cm.
"Due to the uneven road surface water depth can be three to four inches deeper in those areas that ponded early in the flooding.
"River depth has increased overnight to 2.45m
"Some traffic is still travelling through but around 50 per cent is turning around.
"Share this page to get the word out to more road users and avoid risks and extra mile detours.
"The air temperature is low at the moment at two degrees C, be careful of icy patches on the wet roads across the washes.
"As always drive with care and consideration for others."
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