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and their costs and benefits, potentials, and limitations. The following are examples of
adaptations to coastal flooding vulnerabilities.
1) UK / LONDON ADAPTATION PLANNING
In the late 1970's, London built the Thames Barrier in response to significant losses of life
during a 1953 storm in the North Sea. This is a wall of towers that support rotating gates,
which are closed when storm surges are predicted. It uses an energy-efficient design
(rotating wheels that lift the barrier gates), and has been very successful. The system is
being expanded with the East London Green Grid, a park system designed to provide
flood storage along all the tributaries to the Thames in East London and southeast Lon-
don. These parks have also been located to improve local communities' access to nearby
recreational areas, introducing a social justice component into the primary stormwater
detention strategy. London plans to expand this new network system into an “All Lon-
don Green Grid” in the future, creating corridor systems for wildlife and plant dispersal
throughout the greater London area at the same time they provide stormwater manage-
ment and recreation for people. A citywide lood management plan is being writen
(DRAIN London) as a component of a very thorough urban adaptation plan, which is
the most inclusive of its kind in the world. This climate change adaptation planning
document is required by law for Greater London. In addition, the national Environ-
ment agency in the UK has been planning “adaptive pathways” for the Thames Estuary
area that basically (1) identifies possible adaptation strategies, (2) organizes them into
sequences of actions (“pathways”), and (3) lays them out next to a range of sea level rise
scenarios to reveal which pathways would be sufficient to protect London against any
given sea level rise scenario. The plan does, however, incorporate the idea that money
should be allocated and spent only when the environmental change occurs - i.e., sea
level actually reaches critical new levels, indicating imminent danger. The flaw in this
strategy is that national borrowing capacity may not be available at reasonable rates at
that future time. In contrast, Dutch adaptation planning works on the assumption that
investments should be made while interest rates are low and funds are available, well in
advance of the actual environmental change that is expected.
Like the British, the Dutch have also added movable barriers to their coastal defenses.
The Roterdam Maeslantkering was constructed using two 800-foot long fans of space-
frame metal tubing to support a curving steel face wall, which rotate into place on large
ball joints. The steel fans are raised hydraulically, by flooding their storage compart-
ments, then rotated out into the water and lowered once they are in position in the chan-
nel. A miniature version of this design has been incorporated into the newly-built New
Orleans storm surge barrier, designed by a team of Dutch companies, and has been pro-
posed as part of a protection scheme for New York City as well.
The Dutch have partnered with the World Wildlife Fund to move their dikes back
from the river channels in several key areas where additional flood storage is needed.
This national effort, known as the Room for the Rivers Program, has required farmers to
adjust to a lower standard of flood risk protection outside the new dike locations. It has
also created opportunities to experiment with vegetation management, and the reintro-
duction of older catle species that can browse riparian areas and prevent woody plants
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