Case study:Skjern River Project
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Project overview
| Status | Complete |
|---|---|
| Project web site | http://www.SkjernEnge.dk |
| Themes | Fisheries, Habitat and biodiversity, Social benefits |
| Country | Denmark |
| Main contact forename | Niels Dahlin |
| Main contact surname | Lisborg |
| Main contact user ID | |
| Contact organisation | The National Forest and Nature Agency (Denmark) |
| Contact organisation web site | http://www.naturstyrelsen.dk/ |
| Partner organisations | |
| Parent multi-site project | |
| This is a parent project encompassing the following projects |
No |
Project summary
In within a catchment area of 250,000 hectares, the River Skjern (in western Jutland) is the largest river in Denmark in terms of water flow. Previous to human alteration, there was a huge expanse of marshland (4,000 ha) with a mixture of reed-swamps, meadows, meandering watercourses and shallow lakes at mouth of the river.
The delta area constituted the habitat for thousands of migratory bird species and also for stable breeding populations of bittern ("Botaurus stellaris"), black tern ("Chlidonias niger") and corncrake ("Crex crex"). Other species (i.e. European otter ("Lutra lutra"), Atlantic salmon ("Salmon salar"), etc.) were also relatively common until the 1960’s, following the straightening and channelizing of the Skjern and the cultivation of the marshland. This had negative impact on wild flora and fauna species, and dealt to water quality issues with severe effects of the fish and waterfowl populations of Ringkoebing Fjord.
In 1987, the Danish government decided to launch a major strategy to restore marginal areas to their former natural state and to introduce more compatible land use. The River Skjern was to be the milestone of this strategy.
The part involving restoring areas of conservation value of the Skjern was brought as a LIFE-Nature project in January 2001. The "Restoration of habitats and wildlife of Skjern River" aimed to restore 875 ha of the river valley and to improve biological diversity over 1,600 ha by re-introducing grazing. Construction work in the river bed and its tributaries was undertaken for re-meandering 20 km of the river along a more natural course. This enhanced nutrient retention capacity of the river system and enhanced the physical conditions of the site.
By the end of project in December 2004 about 1,200 ha of grassland were established, which was less than originally foreseen (1,600 ha). The reason is that the restoration work finally resulted in increased areas of floodplain. However, these extended wetland areas have benefited important species such as the spotted crake ("Porzana porzana"), avocet (Recurvirostra spp.) and bittern (Ardeidae spp.) and consequently will lead to more enhanced nature conservation.
Monitoring for the assessment of the ecological conditions in the restored area started in 2000. From 2004, the environmental monitoring programme for the project area is part of the national environmental monitoring programme (NOVANA). This surveillance monitoring is more extensive compared to the 2000-2003 monitoring programme for the Skjern River project area.
Monitoring surveys and results
Lessons learnt
Catchment and subcatchment
Site
| Name | |
|---|---|
| WFD water body codes | |
| WFD (national) typology | |
| WFD water body name | |
| Pre-project morphology | |
| Reference morphology | |
| Desired post project morphology | |
| Heavily modified water body | |
| National/international site designation | |
| Local/regional site designations | |
| Protected species present | |
| Invasive species present | |
| Species of interest | |
| Dominant hydrology | |
| Dominant substrate | |
| River corridor land use | |
| Average bankfull channel width category | |
| Average bankfull channel width (m) | |
| Average bankfull channel depth category | |
| Average bankfull channel depth (m) | |
| Mean discharge category | |
| Mean annual discharge (m3/s) | |
| Average channel gradient category | |
| Average channel gradient | |
| Average unit stream power (W/m2) |
Project background
| Reach length directly affected (m) | |
|---|---|
| Project started | |
| Works started | |
| Works completed | |
| Project completed | 2004/12/31 |
| Total cost category | |
| Total cost (k€) | 37926811.0037,926,811 k€ <br />37,926,811,000 € <br /> |
| Benefit to cost ratio | |
| Funding sources |
Cost for project phases
| Phase | cost category | cost exact (k€) | Lead organisation | Contact forename | Contact surname |
|---|---|---|---|---|---|
| Investigation and design | |||||
| Stakeholder engagement and communication | |||||
| Works and works supervision | |||||
| Post-project management and maintenance | |||||
| Monitoring |
Reasons for river restoration
| Mitigation of a pressure | |
|---|---|
| Hydromorphology | |
| Biology | |
| Physico-chemical | |
| Other reasons for the project |
Measures
Structural measures
| |
|---|---|
| Bank/bed modifications | Barriers removal |
| Floodplain / River corridor | Creation of wetlands |
| Planform / Channel pattern | Re-meandering of channel to increase nutrient capacity and improve physiscal condictions |
| Other | |
Non-structural measures
| |
| Management interventions | Monitoring strategy |
| Social measures (incl. engagement) | Creation of a working group and an advisory board were established with representatives from local and national authorities and NGOs. |
| Other | |
Monitoring
Hydromorphological quality elements
| Element | When monitored | Type of monitoring | Control site used | Result | ||
|---|---|---|---|---|---|---|
| Before measures | After measures | Qualitative | Quantitative | |||
Biological quality elements
| Element | When monitored | Type of monitoring | Control site used | Result | ||
|---|---|---|---|---|---|---|
| Before measures | After measures | Qualitative | Quantitative | |||
| Fish | Yes | Yes | No | Yes | No | Improvement |
| Invertebrates | Yes | Yes | No | Yes | No | Improvement |
Physico-chemical quality elements
| Element | When monitored | Type of monitoring | Control site used | Result | ||
|---|---|---|---|---|---|---|
| Before measures | After measures | Qualitative | Quantitative | |||
Any other monitoring, e.g. social, economic
| Element | When monitored | Type of monitoring | Control site used | Result | ||
|---|---|---|---|---|---|---|
| Before measures | After measures | Qualitative | Quantitative | |||
Monitoring documents
Image gallery
Additional documents and videos
Additional links and references
Supplementary Information
Edit Supplementary Information