The Clacton to Holland-on-Sea (UK) stretch of coastline has suffered from significant sediment loss, which negatively impacts the local community and economy. Collectively, five kilometres of beach are at risk of washing away including nearby tourism promenades and over 3000 homes and businesses. In response, a major sea defence project is underway to fortify the coast through construction of new rock groynes and beach nourishment activities. It is expected that this project will reduce coastal erosion for the next 100 years.
Based on information from the Tendring Destrict Council.
General description
The beach area at risk is five kilometers long and runs from Clacton Pier to Holland Haven in Essex on the east coast of England. The project involves using 23 fishtail rock groynes, each 90 meters long and 220 meters apart, and adding roughly 950 000 cubic meters of sand and shingle beach material to the coastline
The project is the biggest of its kind to ever be undertaken by the Tendring District Council. It was approved by the UK Environmental Agency in 2013 and costs roughly 36 million pounds, with support from several funding organizations.
The groyne and beach recharge activities were effective, on time, and on budget. The materials for the rock groynes were made up of the crushed materials from the existing structures and new smaller rocks from a quarry, and were covered by a geotextile once in place in the sea. Larger rocks were placed on the geotextile and the groynes were designed in a fishtail style. The fishtail design of the groynes was chosen to allow dual protection, with the bigger arm blocking waves from the North Sea and the little arm blocking waves from Kent. The materials for beach recharge came from a licensed dredge site and was made up of sand and shingle (a mix of sand, gravel and cobbles, mimicking the natural beach material of the area. During high tide, a dredging ship would pump this mix through a pipe onto the beach, forming an 18 metre wide crest about one metre below the promenade walking level.
Pumping the sand and shingle mix early in the project towards the shore created a platform to help construct the many fishtail rock groynes and support the heavy construction machinery used on the beach during construction. Even with all the groynes, periodic beach re-profiling will be necessary in the future due to coastal processes.