Case study:HPP Blanca
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Project overview
| Status | Complete |
|---|---|
| Project web site | |
| Themes | |
| Country | Slovenia |
| Main contact forename | HESS d. o. o. |
| Main contact surname | HESS d. o. o. |
| Main contact user ID | |
| Contact organisation | HESS d.o.o. |
| Contact organisation web site | |
| Partner organisations | |
| Parent multi-site project | |
| This is a parent project encompassing the following projects |
No |
Project summary
The fish pass on HPP Blanca is the first case of fish way on Sava river HPPs. It is located on the right part of HPP Blanca dam and constructed in the way of imitation of natural watercourse with hydrological characteristics, morphology, materials and varied habitat. The water level in the accumulation lake is changing for 1 m on the daily basis, which is why the inflow in fish pass has vertical slot pass with hydraulic barriers. Water velocity in the fish pass does not exceed 1 m/s. The flow is adjusted on fish migration and hydraulic scheme of the accumulation lake (http://www.he-ss.si/pdf/he_blanca-primer_dobre_prakse.pdf).
In order to bridge the differences in elevation, which is 9.4 m, the length of crossing is 680 m. Of these, 110 m of concrete section (intake facility on the upstream side) and 570 m of sustainable segment, in which also the culvert under a public road and drainage section is included (designed to attract fish). Water outflow from the fish pass itself attracts fish (http://www.he-ss.si/pdf/kratek-opis.pdf).
After the construction of HPP and fish way in 2009 the monitoring began and is still going on. The method used was electrical hunting and fish nets. In 2011 also telemetry was included in monitoring. Results showed that 32 of 40 fish in Sava river on the area of HPP Blanca was evidenced in the fish way (among them also Chrondrostoma nasus), since the beginning of the monitoring, which is good result.
The base for this project, which was done by IBE d. d., was interest in fish species composition in lower Sava river, the assessment of population size for each species, biological characteristics and ecological needs of species. Recommended guidelines and literature about fish passes were basis for the project scheme. The fish experts from Fisheries Research Institute of Slovenia were included in the project from the beginning, which is very good progress in cooperation between experts and energy producers. Even more progress can be done with founding the permanent monitoring of fish way function and maintenance (http://www.he-ss.si/pdf/he_blanca-primer_dobre_prakse.pdf).
Monitoring surveys and results
Lessons learnt
Catchment and subcatchment
Edit the catchment and subcatchment details
(affects all case studies in this subcatchment)
Catchment
| River basin district | Danube River Basin District |
|---|---|
| River basin | Danube |
Subcatchment
| River name | Sava River |
|---|---|
| Area category | 100 - 1000 km² |
| Area (km2) | |
| Maximum altitude category | 200 - 500 m |
| Maximum altitude (m) | 270270 m <br />0.27 km <br />27,000 cm <br /> |
| Dominant geology | |
| Ecoregion | Dinaric Western Balkan |
| Dominant land cover | Wetland |
| Waterbody ID |
Other case studies in this subcatchment: LIFE 06 NAT/SLO/000069 Intermittent Lake Cerknica
Site
| Name | River Sava near settlement Blanca |
|---|---|
| WFD water body codes | SI1VT739 |
| WFD (national) typology | |
| WFD water body name | VT Sava Boštanj – Krško |
| Pre-project morphology | |
| Reference morphology | |
| Desired post project morphology | |
| Heavily modified water body | No |
| National/international site designation | |
| Local/regional site designations | |
| Protected species present | No |
| Invasive species present | No |
| Species of interest | |
| Dominant hydrology | Artificially regulated |
| Dominant substrate | Gravel, Cobble |
| River corridor land use | Extensive agriculture, Woodland |
| 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 | 2009/01/01 |
| Works started | 2009/01/01 |
| Works completed | 2009/08/01 |
| Project completed | |
| Total cost category | |
| Total cost (k€) | |
| 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 | Fisheries Research Institute of Slovenia | ||||
| Stakeholder engagement and communication | |||||
| Works and works supervision | |||||
| Post-project management and maintenance | |||||
| Monitoring | Fisheries Research Institute of Slovenia |
Reasons for river restoration
Measures
Structural measures
| |
|---|---|
| Bank/bed modifications | new river-bed near old channel |
| Floodplain / River corridor | |
| Planform / Channel pattern | creation of fish pass |
| Other | |
Non-structural measures
| |
| Management interventions | monitoring of fish in the fish pass |
| Social measures (incl. engagement) | improved cooperation between energy producers and ecologists |
| Other | |
Monitoring
Hydromorphological quality elements
| Element | When monitored | Type of monitoring | Control site used | Result | ||
|---|---|---|---|---|---|---|
| Before measures | After measures | Qualitative | Quantitative | |||
| Flow velocities | Yes | |||||
Biological quality elements
| Element | When monitored | Type of monitoring | Control site used | Result | ||
|---|---|---|---|---|---|---|
| Before measures | After measures | Qualitative | Quantitative | |||
| Fish: Species composition | Yes | |||||
| Fish: Abundance | Yes | |||||
| Fish: Disturbance-sensitive species | Yes | |||||
| Fish: Age structure | Yes | |||||
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
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_and_sampling_with_fishing_net_(on_the_right)_on_Blanca_HPP_(photo_D._Zabric)..png)
Additional documents and videos
Additional links and references
| Link | Description |
|---|
Supplementary Information
Edit Supplementary Information
REFERENCES:
Zabric D. 2011. Prehodi za ribe pri HE Blanca – primer dobre prakse. Življenje vodi, str. 19–22. Availabe at: http://www.he-ss.si/pdf/he_blanca-primer_dobre_prakse.pdf
HESS d. o. o. Brežice. 2010. Prehod za vodne organizme na HE Blanca. Availabe at: http://www.he-ss.si/pdf/kratek-opis.pdf
Zabric, D., Jenic, A., Videmšek, U. 2012. Ihtiološki pregled na HE Boštanj in HE Blanca v letu 2012. / Ichtyological research at the HPP Boštanj and HPP Blanca in 2012. Report. Ljubljana.
Zabric, D. 2010. Ihtiološki pregled na HE Boštanj in HE Blanca - Monitoring ribje steze HE Blanca. / Ichtyological research at the HPP Boštanj and HPP Blanca – Monitoring of the fish migration aid at HPP Blanca. Report. Ljubljana.