The New Forest supports some of the most important and rare wetland habitats in Europe including bog and riverine woodland, valley mires and wet grasslands – it contains 75% of the valley mires in north-western Europe (90 out of 120). However, past generations (notably the Victorians) altered and straightened the courses of streams to drain land in order to plant trees and improve grazing conditions, thereby threatening these valuable habitats. The loss of stream meanders has led to an overall reduction in stream length which causes water to run through the shortened channel section more rapidly downstream taking with it valuable nutrients and gravel deposits. The Forestry Commission and other agencies have a legal responsibility under the EU Habitats Directive for restoration of wetland habitat that has been assessed by Natural England as being in unfavourable condition.
On this occasion all the main players, including the Forestry Commission, National Park Authority and New Forest Verderers are in favour of this restoration work but, perhaps unsurprisingly, there is a small vociferous minority opposing the works in their “back yards” which is giving rise to lengthy consultations at the taxpayers’ expense!
These habitat restoration works aim to restore the meandering course (and original dimensions) of the Forest streams and infill the redundant drain that is left behind. Old Forest maps are used to ensure that the remedial work closely follows the original course of each stream. Without this work, due to their artificially over deepened channels, these streams are unable to repair themselves and undo the drainage works of previous generations, while the erosion of the stream beds continues. This work has been ongoing since 1997 and is carried out by specialist contractors. Their remedial work has been very successful to date and without the further work that is planned, there will continue to be increased erosion and transport of gravel from stream beds that in turn can lead to problems further down the stream’s course. These gravels are deposited when the gradient of the stream reduces leading to a reduction in channel capacity downstream, which in turn causes drainage problems and flooding.
Once re-instated the streams flood naturally onto their floodplains and, unlike before, can act as a natural water storage area providing improved grazing material for ponies and cattle. The works should also promote significant benefits for bird life and the RSPB will be monitoring the increase in population of wading birds.
All of these works are funded through DEFRA under the Higher Level Stewardship Scheme and the following video gives an example of how this work is undertaken.