By Michelle Gostic (COMEM student):
In another installation of the coastal seminar series, graduate students of the Coastal and Marine Engineering and Managmenet (CoMEM) and the Engineering in th e Coastal Environment (ECE) masters programs had the pleasure of attending a talk by Dr. Anjana Ford titled “Coastal Conflicts: Managing the Jurassic Coast World Heritage Site.” As a member of the Jurassic Coast Trust, the organization responsible for managing the UNESCO World Heritage designated coastline, Anjana challenged our engineering instincts and offered a unique perspective on managing dynamic coastlines of historical and scientific importance.
To earn World Heritage Site (WHS) status, a site must have “outstanding universal value.” After 8-10 years of working to get the Jurassic Coast accepted as a UNESCO WHS site, the unique coastline earned designation in 2001. The Jurassic Coastline’s outstanding universal value exists in its landforms, rocks, and fossils, and it earned designation based on its incredible historic geologic value. The 95 miles of coast, capture an astounding 185 million years of the Earth’s history, representing 3 periods of geologic time. By walking from east to west, one can experience the limestone and chalk of the cretaceous period, the shales and clays of the Jurassic period, and finally sandstone from the Triassic period. The fossils found along the Jurassic Coast have provided invaluable portals into the history of life and the creatures that inhabited our planet millions of years ago. Just this month, BBC published an article about a fossil found in Dorset that is believed to be from the earliest mammals to have walked the earth (see article here).
To truly preserve the Jurassic Coast’s outstanding universal value, the natural geology, geomorphology, and the processes that govern these impressive coastal features must be conserved. From the perspective of the Jurassic Coast Trust and those that wish to uphold their mission, allowing big waves to continue to hit the erodible cliffs is at the core of maintaining the outstanding universal value of the coastline. By allowing dynamic forces to unabatedly shape and erode the coastline, fossils previously trapped in the sediment are revealed and the resulting morphology remains a pure manifestation of natural processes.
However, some residents living along the coast – in pockets excluded from the WHS designation – feel differently about how to manage the Jurassic Coast. Derek Hallet, a man living in Lyme Regis, a city situated in an active landslip zone subject to rapid erosion rates, was interviewed about what it’s like to quite literally be living life on the edge, as the garden adjacent to his house situated on top of a cliff has already succumbed to erosion. He recounted, “I used to go to bed with my lifejacket on just in case!”
The situation in Lyme Regis became somewhat contentious. Some argued for the construction of coastal protection and erosion prevention measures, like enhanced sea walls, nourishment, or breakwaters. Others believed that the natural processes governing the processes should be conserved to maintain the 185 million years of history contained in the Jurassic Coastline.
Eventually, a solution was reached that satisfied both parties. Many measures were taken to stabilize the land in Lyme Regis without compromising the natural processes in the WHS zone adjacent to the city. Soil nails and mesh were installed throughout the area to stabilize the land. Improvements to an outdated and problematic drainage system were made the sea wall was extended in such a way that encroached on the WHS area, but did not disturb any areas of special interest. The collaboration and cooperation between coastal engineers and morphologists was the key to success in this case. We should bear this lesson in mind, as climate change is likely to create more challenging coastal management questions as other areas of historical, cultural, or scientific importance become threatened.