These are issued by Norfolk County Council and listed on the Highways part of their website as Public Information Notices here https://www.norfolk.gov.uk/roads-and-transport/roads/traffic-orders-notices-and-restrictions/public-information-notices
Notices with maps are posted when appropriate in the Parish notice boards for any closures affecting Burston, Shimpling, Mill Green and Audley End.
STRO4970-Diss-ShelfangerRoad – Parts of Shelfanger ~Road going into Diss will be closed for footway works around the 6th June and for part of July. Please the map for the long diversion routes and full details.
For other road information around the UK there is a useful map here Roadworks, diversions and accidents on the one.network web site; zoom in to Norfolk for more local details.