Constructed Wetlands 
Constructed Wetlands
for
Flood Plain Defense
YES
believe Constructed Wetlands can be part of the overall
solution for flood defenses. They are low maintenance, long lasting, and low
cost.
An area of 1000m2, could store 1500m3 of water,
releasing excess water once river levels have returned to normal. Such an area
could be constructed within a week, and cost no more than £20,000. This is an
approximate cost for construction, planting, riverside erosion measures, and
perimeter fencing. If such a construction was applied in many places along a
river prone to flood, the impact could be significantly reduced.
Excess flooded river flows can be stored over large areas of land, developed as Constructed Wetlands. A number of such developments, along a river, can greatly reduce the impact of river flooding events. The Planting of Reeds provides significant levels of evapor-transpiration. The flood water can be released once the river levels return to normal.
The flood water flows over and through a gypsy stone and gravel construction, to dissipated the energy of flow. They collect in an area of approximately 1000m2 ( possibly 2000m3 ), and are stored behind a correctly built 2m high clay bund wall. A valve outlet is built into this bund wall to release stored water once river levels return to normal.
There would be issues of land ownership and use. Some
joined up thinking among government, local government and land owners could
prove mostly successful.
Question :- Could Insurance Companies have an interest in funding flood defenses, along with government and local government ?
I can hear the voices of dismissal, suggesting such system can’t possibly work. These are the same voices I have heard for the past 12 years, during which time my reedbeds have consistently proven themselves. My passion is for biological systems, which have proven most resilient over the past 500 million years. I judge myself lucky to have begun to learn and to understand them.
Follow the links below to view the sequence of the design.
See design for Normal Flows Flood Situation and After the flood