Norfolk Beach Sinkhole Reveals Massive Underground Void

Investigations have revealed a significant void beneath a small sinkhole on Hunstanton's beach promenade in Norfolk. Ground penetrating radar surveys indicated the void measures 3.5m (11.4ft) deep and up to 14m (45.9ft) wide in places. As a result, a 140m (1450ft) stretch of the walkway between the Waterside Bar and Oasis leisure centre, along with part of the beach, has been closed off by the Borough Council of King's Lynn and West Norfolk.

The council is currently formulating a repair plan for the promenade, which dates back to the 1920s. Historically, materials used in its construction, including bottles and pottery, have been exposed by sea erosion. The promenade was previously renewed in 1954 after flooding, but current sea levels are exposing its footings and causing further damage.

Repairs are complicated by ongoing high tides and adverse weather conditions. Six kiosks are affected by the closure, though only one was scheduled to open this half-term, with an alternative location secured. In August of last year, over 300 concrete slabs were identified for potential replacement, and a 10-tonne vehicle weight limit was implemented due to concerns about structural failure of the sea wall and the promenade's aging surface. Full repairs are estimated to take over two years and cost multiple millions.