Police are advising motorists to avoid the A127, particularly at the Rayleigh Weir, which remains flooded after Saturday's heavy rain.
Officers are working with the local authority to get the water pumped away and reopen the road as soon as possible.
Over 200 incidents of flooding were reported to police on Saturday with areas worst affected including Southend, Canvey, Maldon, Burnham, Battlesbridge and Benfleet.
More top news
Town's Championship game with Brighton part of a busy night for the region's League football clubs
A mix of patchy cloud and clear spells tonight. Bright and warm tomorrow
An animal charity has warned that 700 stray dogs in the Anglia region faced destruction because microchip details were out of date.