Action Examples: United Kingdom – Managed Retreat
Introduction:
For many years, coastal landowners in Britain have tried to protect their land and homes by building seawalls. However, sea levels are rising faster than humans can keep the water out. At Abbott’s Hall Farm in Essex, England, five holes have been made in the existing seawall, creating up to 300 acres of salt marsh and grazing marsh at a cost of £3 million.
Analysis:
This sacrificed land would have turned into mud flats or salt marshes on its own years ago (but had been protected by the seawall before it deliberately was breached). Sacrificing land acts to absorb energy from incoming waves, reducing their impact farther inland. As long as the ground is left alone, it will absorb water and prevent it from traveling so far inland. Thus sacrificing low-lying land actually protects (or saves) nearby slightly higher land.
Sacrificing poorly utilized land also creates a healthy and rich environment for marine species. Salt marshes and estuaries face increased erosion pressure as sea levels rise; England has experienced a 40% loss of salt marshes over the last 25 years. Sacrificing marginal lands can help to replace some of these salt marshes.
England is facing another interesting challenge. During the last ice age, land in northern England and Scotland was weighted down by heavy sheets of ice. The ice is gone, and the land is slowly rising upward out of the sea in a process called “isostatic rebound”. As the land in the north rises out of the sea, the land in the south sinks. England is currently trying to find answers to problems caused by the combination of isostatic rebound and sea level rise.
Sources:
- University of Essex: Walking with Wildlife
- Guardian: "Who needs Essex anyway?"
- Abbotts Hall Information 2000
Photo credits:
*All website references were accessed in April 2005.
