Fingringhoe Ranges, Ministry of Defence

Wave attack to the seawall on this stretch of the Essex coast was limited by the shelter of Mersea Island. However, relatively unstable clay embankments over salt marshes, and across many former creeks and channels were protected by Essex Blocks.

With maintenance taking a large propsortion of the ranges’ annual budget, a more cost-effective Lean Sand Asphalt (LSA)/Open Stone Asphalt (OSA) protection was commissioned.

• 150mm LSA placed as filter and regulating layer
• 150mm OSA armour placed in situ over LSA, following all shapes and contours
• LSA benches placed in particularly unstable areas
• Works phased over 5 years from 1994
• All sections have performed well with no maintenance required to date