The Trust has released a statement saying Maria Ball has resigned with immediate effect.
The process for appointing a new or interim chair will be started immediately but in the meantime Paul Remington who is vice chair will lead the organisation with Andrew Morgan, the interim chief executive.
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Norfolk Police are reminding motorists to take extra care as temperatures drop, following a number of collisions around the county.
Temperatures may have plunged at the close of the year but 2014 will be written up in the record books as the hottest ever in East Anglia.
Around 5,000 homes remain without water in Norfolk today, meaning that water bowsers have been brought in. Here's where you can find them.