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The Skjern
River Skjern - Denmark
The
Skjern is Denmark's largest river, draining over 10% of the mainland before
discharging through the broad shallow Ringkobing Fjord to the North Sea.
Less than 40 years ago the lower river catchment supported a rich mosaic
of watercourses, lakes, ponds, reedbeds, meadows, common grazing land
and heathlands. In times of flood, an enormous lake was formed, interrupted
only by boggy marshlands.
Between
1962-68 the river was straightened, deepened and embanked, and gradually
the wetlands, meadows and heath were turned into a 4000ha, arable prairie.
This was Denmark's largest drainage project, equating to around £22m
today. However the gains for agriculture were not as easily sustained,
as first thought. As floodwater no longer flowed over land, and as fertiliser
was liberally applied, the floodplain began to act as a huge 'source'
of nutrients, and was no longer a 'sink' for sediments. This had a disastrous
impact on the fjord as it became silted up and polluted. Problems also
arose in the drainage area itself. The land shrunk as it dried out, and
so land levels dropped making drainage ineffective and water turned bright
red due to ochre precipitation.
In
1987 the Danish parliament took the decision to restore the River Skjern.
By 1998 plans for restoration were ready for implementation and a supporting
act of Parliament was passed. Project objectives included:
- Recreating natural wetland habitats of international
importance
- Developing the valley for 'nature' tourism and leisure
as an alternative income to intensive agriculture
- Improving the aquatic environment of the downstream
fjord as a result of the works upstream
Work
is progressing to schedule with half already completed. Much of the straightened
and embanked section of the River Skjern no longer carry any flow, and
have either been partially retained as linear ponds, or been in-filled
with material that arose as new meandering channels had been constructed.
Where less than three years ago there was not a puddle of water, vast
winter lakes now appear as floodwater is again stored on the floodplain
as the newly meandered river over-tops its banks. Almost £1.5m is
being spent on monitoring the effects of the project on the quality of
the fjord and the environments of the river and the floodplain.
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