Framework

YORcivil2

Client

Scarborough Borough Council

Contractor

Esh Construction Limited

Value

£1,200,000

Coastal defense scheme provides security for the community and wildlife

* Winner of the Innovation category, Constructing Excellence Yorkshire and Humber Awards 2019 *

The Scarborough sea walls were bolstered with concrete repairs and 10,000 tonnes of granite boulders and made special provision to encourage sea life.

The Jurassic bedrock and glacial sediments of the Runswick Bay coastline are susceptible to landslides and erosion. The newly constructed scheme offers 100 years of better protection to 96 residential and 17 non-residential properties, all would otherwise have been lost to erosion.

Protecting the community

The ongoing risks of degradation to the sea wall and the stability of the slopes behind have been a major concern for the community. The historic concrete sea wall had reached the end of its serviceable life with a predicted failure/loss within the next 10 years. The new revetment scheme is also designed to combat the effects of sea level rise and provides increased protection in storm conditions which are predicted to increase in frequency as a result of climate change.

The toe of the sea wall is now bolstered by rock armour 2 meters high and 8 meters wide. Designers assessed wave energy to best determine the profile of the rock allowing it to sufficiently reduce the impact on the wall. The areas most prone to wave impact were protected with larger rocks set at a steeper profile.

The Norwegian granite boulders, each weighing between 8 and 10 tonnes, were delivered onto the beach from a barge.

Encouraging wildlife

Coastal defences typically have lower biodiversity than natural rocky shores. To make better provision for wildlife, over 120 rock pools were cut into the granite granite boulders, and over 130 groove sections were carved into the surface to cater for small crustaceans.

Within two weeks of the creation of this habitat it had begun to be colonized by sea life.

CEYH2019 award winner

Runswick Bay Coastal Defence Scheme was the winner of the Innovation category at the Constructing Excellence Yorkshire and Humber Awards 2019. The entry was submitted by the client, Scarborough Borough Council.

CEYH2019 Award winners and highly commended