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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It has been a chilly night in the Anglia region with temperatures plunging below -6°C at Writtle in Essex.
Cold, bright and frosty across most areas to start but cloudier towards the northwest of the Anglia region.
The Care Quality Commission has changed the rating of Addenbrooke's hospital from 'inadequate' to 'good' following a re-inspection.