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.
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With the cold weather expected to last for at least the next five days, the Met Office has issued various snow and ice warnings.
Cold but dry and bright this afternoon followed by a risk of icy stretches tonight.
Colchester General Hospital has been branded inadequate by the Care Quality Commission. It follows an inspection on 12 November 2014.