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One method is to act construct a barrier so when the fallen trees and shrubs are placed behind the barrier the running water and debri is prevented from washing away. This method is more effective than the one below as it holds more water back, has a higher level of overflow and more valuable fertile
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A variety of solutions was put forward including using naturally occurring composting materials in path of flow to hold valuable fertile silt and dam up waters over many small dams. A leaky dam was added to the arsenal of flood prevention tools. This type of structure is what nature uses for similar
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It would seem local residents, environmental agencies, local councils and budget managers are more open to a natural flow system that mimics nature and holds large volumes of water back for later draining. The biggest motivator is this method costs a fraction of the hard defenses that professional
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events. Logs from fallen trees are placed at intervals down the stream acting as a barrier, holding the silt and small debris back and allowing just the water that overflows the structure to continue the course of the stream.
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Artificial leaky dams constructed from injection molded plastic have also been tried in some areas. Some of the benefit derived from this method is the wall doesn't corrode or compost over time requiring less management.
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ending up in flood areas and river beds. It costs a fortune to collect the soil from river beds, estuaries and river mouths, decontaminate, transport and physically replace the reclaimed sand.
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was initiated. One of the proposals put forward was containing flood waters at source to prevent large volumes of water flowing downstream causing soil erosion and flooding of properties.
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A well known project in
Pickering, North Yorkshire, UK showed how effective leaky dams can be when there projected flooding risk assessment dropped from a 25% probability to about 4%.
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After a heavy downpour, soil, gravel, silt and valuable nutrients are lost when the rains wash away the top soil. This animation of a side view of a mountain embankment shows how bad
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These are deemed soft defenses as opposed to hard defenses that include solid concrete retaining walls that cost a fortune and are unsightly to local people.
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are a flooding prevention measure, moderating the flow of water downstream. Barriers are added to a stream/river to prevent soil and
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The area surrounding the leaky dams have many benefits including better quality of water to life behind the barrier, prevention of
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More vegetation is able to be supported behind the barrier due to the higher level of nutrients captured from debri and silt.
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Surrounding vegetation is able to absorb more water and nutrients from standing body of water rather than a flowing one
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Another method is to place fallen logs in a zigzag pattern that would mimic nature in the event of a natural felling.
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The idea of these dams is to create a method whereby the water can slowly drain into the surrounding water table.
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Many county bodies have initiated their own trials and photographic and video recordings show positive results.
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The larger the tree, the better the root growth, the more water is absorbed and the more soil is held together.
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Water isn't dammed up as much with this method but valuable silt is still filtered and not lost downstream.
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Theses are types of barriers used by organisations in UK to prevent soil erosion and flooding downstream.
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Some trees can absorb hundreds of litres per day, making it a very effective water collection system
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This method is favoured by environmental groups who claim that it closely resembles nature.
498:"Pickering and District Civic Society - Debris Dams during the high flows of 4 April 2012"
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Aquatic life is able to populate and continue to multiply with limited inventions.
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629:"September | 2015 | The official blog for the North York Moors National Park"
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384:"What next for Water Friendly Farming? - Freshwater Habitats Trust"
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With the regular flooding of settlements in the UK, a rethink on
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Aquatic life can move between barriers and continue upstream.
360:"UK floods: 'Complete rethink needed' on flood defences"
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escaping and allowing water to escape at a slower rate.
409:"Damned if we don't - flood defences | Big Issue North"
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653:Ltd), Paul Allington (Intelligent Penguin.
307:. Unsourced material may be challenged and
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327:Learn how and when to remove this message
633:northyorkmoorsnationalpark.wordpress.com
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447:"pdf of forestry site using leaky dams"
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270:government agencies have been promoting
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605:"Build a Leaky Dam and do Your Bit!"
502:www.pickeringcivicsociety.btck.co.uk
305:adding citations to reliable sources
655:"Plastic Piling Control Structures"
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481:"forestry project with photos"
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580:"FWAG SouthWest on Twitter"
522:"FWAG SouthWest on Twitter"
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563:"pdf of leaky dam project"
388:Freshwater Habitats Trust
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546:"pdf of tree statistics"
464:"somerset leaky dam pdf"
433:"lecture of leaky dam"
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33:flood risk management
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635:. 28 September 2015
609:www.wookeyhole.info
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685:Dams by type
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299:Please help
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252:Observations
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145:Barriertypes
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55:Soil erosion
49:soil erosion
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679:Categories
664:2016-04-04
639:2016-04-04
614:2016-04-03
589:2016-04-03
531:2016-04-03
507:2016-04-13
418:2016-04-03
394:2016-04-03
369:2016-04-03
346:References
17:Leaky dams
288:does not
364:BBC News
87:Examples
43:Benefits
584:Twitter
526:Twitter
309:removed
294:sources
65:topsoil
27:History
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