Case study:Restoration of the river Børselva: Difference between revisions
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{{Case study status | {{Case study status | ||
|Approval status= | |Approval status=Approved | ||
}} | }} | ||
{{Location | {{Location | ||
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{{Project overview | {{Project overview | ||
|Status=In progress | |Status=In progress | ||
|Themes=Habitat and biodiversity, Hydropower, Hydromorphology, Land use management - agriculture | |Project web site url=www.borselva.no/bakgrunn/bakgrunn.php | ||
|Themes=Fisheries, Habitat and biodiversity, Hydropower, Hydromorphology, Land use management - agriculture, Monitoring | |||
|Country=Norway | |Country=Norway | ||
|Main contact forename=Lars | |Main contact forename=Lars | ||
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|Partner organisations=The Norwegian Water Resources and Energy Directorate (NVE), Ballangen Energi AS, Norwegian Institute for Water Research (NIVA) | |Partner organisations=The Norwegian Water Resources and Energy Directorate (NVE), Ballangen Energi AS, Norwegian Institute for Water Research (NIVA) | ||
|Multi-site=No | |Multi-site=No | ||
|Project summary= | |Project picture=Borselva.jpg | ||
|Picture description=A newly opened (macrophyte removal) section of Børselva, including sedimentation pond (far left) and consecutive constructed wetlands. Source: Aanes et al 2016 (NIVA report 6900-2015) | |||
|Project summary=In 1999, before the measures were carried out, there were problems with siltation and overgrowth of macrophytes in the river channel, due to the greatly reduced water flow resulting from hydropower production and agricultural drainage. There were very poor conditions for fish and other aquatic organisms. Nearly 70% of the water area in Børselva was covered by plants. Important habitats for wetland birds were in danger of disappearing. Large areas of trout spawning and growing areas were destroyed. | |||
Measures implemented | Measures implemented in the agricultural channel ("Bruksåskanalen") included erosion control, establishment of sedimentation ponds with vegetation filters and revegetation along the channel. Three paved thresholds were established in Børselva, with the laying of spawning gravel. 1 km of the overgrown part of the river was opened with an excavator and fiber fabric was laid, with stone and gravel on top. Dredging and opening of the rest of the Børselva with a large excavator ("Langemann") was carried out. Different water discharges in Børselva (from the dam in Børsvatnet) were tested - with the main focus on “flushing floods” and winter water flow. | ||
|Monitoring surveys and results=The condition in 2019 after the rehabilitation work showed major environmental improvements, but the environmental objectives of good chemical status and good ecological potential have not yet been reached. Further measures are required to reduce agricultural runoff and to implement the final regime for environmentally based water discharges. As of 2019, the hydroelectric license is under review at NVE (The Norwegian Water Resources and Energy Directorate). | |||
Litterature e.g.: | |||
www.fylkesmannen.no/contentassets/74f02cdd90cb485ea8def16785a345d3/ballangen---borselva---2016---etterundersokelser-etter-restaureringstiltak---vannvegetasjon-og-fisk---niva-rapp-7083-2016.pdf | |||
|Lessons learn=The measures in the Børselva watercourse (Børselvvassdraget) have created better water quality and hydrological continuity (open water flow) in the formerly overgrown watercourse. The flow levels have improved, self-cleaning has improved and pollution has been reduced. This has resulted in a more varied benthic fauna, better spawning and growing conditions for the trout and improved conditions for the bird fauna. | |Lessons learn=The measures in the Børselva watercourse (Børselvvassdraget) have created better water quality and hydrological continuity (open water flow) in the formerly overgrown watercourse. The flow levels have improved, self-cleaning has improved and pollution has been reduced. This has resulted in a more varied benthic fauna, better spawning and growing conditions for the trout and improved conditions for the bird fauna. | ||
|Project title=Restoration of the river Børselva | |Project title=Restoration of the river Børselva | ||
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|Protected species present=Yes | |Protected species present=Yes | ||
|Invasive species present=No | |Invasive species present=No | ||
|River corridor land use=Broadleaf/mixed woodland (semi natural), | |Dominant hydrology=Artificially regulated, | ||
|River corridor land use=Broadleaf/mixed woodland (semi natural), Improved/semi-improved grassland/pasture, Wetland, Tall herb/rank vegetation, | |||
|Mn discharge=0.15 | |Mn discharge=0.15 | ||
}} | }} | ||
{{Project background}} | {{Project background | ||
{{Motivations}} | |Project started=1997/01/01 | ||
{{Measures}} | |Total cost category=100 - 500 k€ | ||
|Total1 cost=296 | |||
|Funding sources=Ballangen Energi AS, The Norwegian Water Resources and Energy Directorate (NVE), | |||
}} | |||
{{Motivations | |||
|Specific mitigation=Hydropower, Land drainage, | |||
|Hydromorphological quality elements=Quantity & dynamics of flow, | |||
|Biological quality elements=Fish, Macrophytes, Invertebrates, Water birds | |||
|Physico-chemical quality elements=Nutrient concentrations, Oxygen balance, | |||
}} | |||
{{Measures | |||
|Bank and bed modifications measure=Cut back of plants, Introduction of spawning gravels, Creation of mini-treshold, Creation of pools, sediment, Sediment trap building, | |||
|Floodplain / River corridor=Erosion protection, | |||
|Management interventions=Reduced pollution, Flow management, | |||
}} | |||
{{Hydromorphological quality elements header}} | {{Hydromorphological quality elements header}} | ||
{{Hydromorphological quality element table row | |||
|Element=Continuity for organisms | |||
|Monitored before=Yes | |||
|Monitored after=Yes | |||
|Qualitative monitoring=Yes | |||
|Quantitative monitoring=No | |||
|Control site used=No | |||
|Result=Improvement | |||
}} | |||
{{Hydromorphological quality element table row | |||
|Element=Substrate conditions | |||
|Monitored before=Yes | |||
|Monitored after=Yes | |||
|Qualitative monitoring=Yes | |||
|Quantitative monitoring=No | |||
|Control site used=No | |||
|Result=Inconclusive | |||
}} | |||
{{Hydromorphological quality element table row | |||
|Element=Quantity & dynamics of flow | |||
|Monitored before=Yes | |||
|Monitored after=Yes | |||
|Qualitative monitoring=No | |||
|Quantitative monitoring=Yes | |||
|Control site used=No | |||
|Result=Inconclusive | |||
}} | |||
{{End table}} | {{End table}} | ||
{{Biological quality elements header}} | {{Biological quality elements header}} | ||
{{Biological quality element table row | |||
|Element=Fish | |||
|Monitored before=Yes | |||
|Monitored after=Yes | |||
|Qualitative monitoring=No | |||
|Quantitative monitoring=Yes | |||
|Control site used=No | |||
|Result=Improvement | |||
}} | |||
{{Biological quality element table row | |||
|Element=Invertebrates | |||
|Monitored before=Yes | |||
|Monitored after=Yes | |||
|Qualitative monitoring=No | |||
|Quantitative monitoring=Yes | |||
|Control site used=No | |||
|Result=Improvement | |||
}} | |||
{{Biological quality element table row | |||
|Element=Macrophytes | |||
|Monitored before=Yes | |||
|Monitored after=Yes | |||
|Qualitative monitoring=No | |||
|Quantitative monitoring=Yes | |||
|Control site used=No | |||
|Result=No change | |||
}} | |||
{{End table}} | {{End table}} | ||
{{Physico-chemical quality elements header}} | {{Physico-chemical quality elements header}} | ||
{{Physico-chemical quality element table row | |||
|Element=Nutrient concentrations | |||
|Monitored before=Yes | |||
|Monitored after=Yes | |||
|Qualitative monitoring=No | |||
|Quantitative monitoring=Yes | |||
|Control site used=No | |||
|Result=Improvement | |||
}} | |||
{{End table}} | {{End table}} | ||
{{Other responses header}} | {{Other responses header}} | ||
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{{Additional Documents end}} | {{Additional Documents end}} | ||
{{Additional links and references header}} | {{Additional links and references header}} | ||
{{Additional links and references | |||
|Link=www.fylkesmannen.no/contentassets/74f02cdd90cb485ea8def16785a345d3/ballangen---borselva---2016---etterundersokelser-etter-restaureringstiltak---vannvegetasjon-og-fisk---niva-rapp-7083-2016.pdf | |||
|Description=NIVA report 6900-2015 (2015): "Børselvvassdraget, Ballangen kommune 2014-2015" | |||
}} | |||
{{Additional links and references | |||
|Link=faktaark.naturbase.no/?id=VV00000213 | |||
|Description=Website in Norwegian | |||
}} | |||
{{Additional links and references | |||
|Link=felles.naturbase.no/api/dokument/hent/18653.PDF | |||
|Description=Pamphlet in Norwegian | |||
}} | |||
{{Additional links and references | |||
|Link=https://niva.brage.unit.no/niva-xmlui/bitstream/handle/11250/211783/4560_72dpi.pdf?sequence=1&isAllowed=y | |||
|Description=NIVA report 4560-2002 (2002): "Børselvprosjektet rapport nr 8. Sluttrapport for del-prosjekt: Minstevannføring og begroingsproblematikk i Børselv-vassdraget" | |||
}} | |||
{{Additional links and references | |||
|Link=https://www.fylkesmannen.no/contentassets/74f02cdd90cb485ea8def16785a345d3/ballangen---borselva---2016---etterundersokelser-etter-restaureringstiltak---bunnfauna---oksygeninnhold---vannforing--niva-rapp-7083-2016.pdf | |||
|Description=NIVA report 7083-2016 (2016): "Børselv-vassdraget, Ballangen kommune: Undersøkelser av bunnfauna, oksygenforhod vinterstid samt vannføring og vannstandsvariasjoner etter restaureringstiltak" | |||
}} | |||
{{Additional links and references | |||
|Link=https://niva.brage.unit.no/niva-xmlui/handle/11250/2478671 | |||
|Description=NIVA reåprt 7148-2017 (2017): "Etterundersøkelser av makrovegetasjon og vannkjemi i Børselva 2016" | |||
}} | |||
{{Additional links and references | |||
|Link=https://niva.brage.unit.no/niva-xmlui/bitstream/handle/11250/2415217/5967-2010.pdf?sequence=1&isAllowed=y | |||
|Description=NIVA report 5967-2010 (2010): Fiskeundersøkelser i Børselvvassdraget, Ballangen kommune, 2009" | |||
}} | |||
{{Additional links and references footer}} | {{Additional links and references footer}} | ||
{{Supplementary Information}} | {{Supplementary Information}} | ||
{{Toggle content end}} | {{Toggle content end}} |
Latest revision as of 09:12, 25 February 2020
Project overview
Status | In progress |
---|---|
Project web site | http://www.borselva.no/bakgrunn/bakgrunn.php |
Themes | Fisheries, Habitat and biodiversity, Hydropower, Hydromorphology, Land use management - agriculture, Monitoring |
Country | Norway |
Main contact forename | Lars |
Main contact surname | Sæter |
Main contact user ID | |
Contact organisation | County Governor of Nordland |
Contact organisation web site | http://www.fylkesmannen.no/nordland |
Partner organisations | The Norwegian Water Resources and Energy Directorate (NVE), Ballangen Energi AS, Norwegian Institute for Water Research (NIVA) |
Parent multi-site project | |
This is a parent project encompassing the following projects |
No |
Project summary
In 1999, before the measures were carried out, there were problems with siltation and overgrowth of macrophytes in the river channel, due to the greatly reduced water flow resulting from hydropower production and agricultural drainage. There were very poor conditions for fish and other aquatic organisms. Nearly 70% of the water area in Børselva was covered by plants. Important habitats for wetland birds were in danger of disappearing. Large areas of trout spawning and growing areas were destroyed.
Measures implemented in the agricultural channel ("Bruksåskanalen") included erosion control, establishment of sedimentation ponds with vegetation filters and revegetation along the channel. Three paved thresholds were established in Børselva, with the laying of spawning gravel. 1 km of the overgrown part of the river was opened with an excavator and fiber fabric was laid, with stone and gravel on top. Dredging and opening of the rest of the Børselva with a large excavator ("Langemann") was carried out. Different water discharges in Børselva (from the dam in Børsvatnet) were tested - with the main focus on “flushing floods” and winter water flow.
Monitoring surveys and results
The condition in 2019 after the rehabilitation work showed major environmental improvements, but the environmental objectives of good chemical status and good ecological potential have not yet been reached. Further measures are required to reduce agricultural runoff and to implement the final regime for environmentally based water discharges. As of 2019, the hydroelectric license is under review at NVE (The Norwegian Water Resources and Energy Directorate).
Litterature e.g.: www.fylkesmannen.no/contentassets/74f02cdd90cb485ea8def16785a345d3/ballangen---borselva---2016---etterundersokelser-etter-restaureringstiltak---vannvegetasjon-og-fisk---niva-rapp-7083-2016.pdf
Lessons learnt
The measures in the Børselva watercourse (Børselvvassdraget) have created better water quality and hydrological continuity (open water flow) in the formerly overgrown watercourse. The flow levels have improved, self-cleaning has improved and pollution has been reduced. This has resulted in a more varied benthic fauna, better spawning and growing conditions for the trout and improved conditions for the bird fauna.
Image gallery
Catchment and subcatchment
Site
Project background
Cost for project phases
Reasons for river restoration
Measures
MonitoringHydromorphological quality elements
Biological quality elements
Physico-chemical quality elements
Any other monitoring, e.g. social, economic
Monitoring documents
Additional documents and videos
Additional links and referencesSupplementary InformationEdit Supplementary Information
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