Case study:LIFE 06 NAT/SLO/000069 Intermittent Lake Cerknica: Difference between revisions

From RESTORE
Jump to navigation Jump to search
No edit summary
No edit summary
Line 262: Line 262:
{{Additional_Documents}}
{{Additional_Documents}}
{{Additional_Documents_end}}
{{Additional_Documents_end}}
{{Additional_links_and_references_header}}
{{Additional links and references header}}
{{Additional links and references
|Link=archive-si.com/si/n/notranjski-park.si/2012-10-05_373223/
|Description=project archive
}}
{{Additional_links_and_references_footer}}
{{Additional_links_and_references_footer}}
{{Supplementary Information
{{Supplementary Information

Revision as of 09:39, 31 May 2013

This case study is pending approval by a RiverWiki administrator.

Approve case study

 

4.00
(one vote)


To discuss or comment on this case study, please use the discussion page.


Location: 45° 44' 33.18" N, 14° 21' 48.01" E
Loading map...
Left click to look around in the map, and use the wheel of your mouse to zoom in and out.


Project overview

Edit project overview
Status Complete
Project web site
Themes
Country Slovenia
Main contact forename Tanja
Main contact surname Vasilevska
Main contact user ID
Contact organisation Notranjski regijski park
Contact organisation web site
Partner organisations
This is a parent project
encompassing the following
projects
RESTORATION OF THE GORIŠKI BREŽIČEK STREAM, RESTORATION OF THE TRESENEC STREAM
This case study hasn’t got a picture, you can add one by editing the project overview.

Project summary

Edit project overview to modify the project summary.


In 2006 Notranjska Regional Park acquired financial support from European programme LIFE – Nature for project LIFE 06. The purpose of this project was the establishment of appropriate conditions for protection and conservation of animal and plant species and their habitats on Lake Cerknica. Factors that threaten the biodiversity on Lake Cerknica are modified watercourses, abandoning of meadow mowing and deficient knowledge of nature and its conservation.

With the intention of maintaining biodiversity on Lake Cerknica efforts were oriented to following actions: • Restoration of watercourses, that would contribute to higher water ground level and retaining of overall water level on Lake Cerknica • Composition of a Management plan, which serves as groundwork for managing the project area and is orientated towards conservation of natural and cultural heritage of Lake Cerknica • Mapping of habitat types with the intention of conserving the endangered ones • Land managing including buying, late mowing and mulching on the permanently protected land. • Popularization of the project and education of the youth on the importance of nature conservation.

The aim of the project was the restoration of former meanders and by doing so retaining the water longer in the dry period and increasing the groundwater level in wetland areas. It was expected that in this way the ecological conditions of the wetland areas, and thereby the living conditions for flora and fauna, improve. Inženiring za vode d.o.o. produced the project documentation, based on a review of the situation on the terrain and examining the location of riverbeds as they were before the regulating operations began. More than 12 km of watercourses in the Cerknica area are included in this study.


                         RESTORATION OF THE GORIŠKI BREŽIČEK STREAM: 

By restoring former meanders of the Goriški Brežiček stream it was intend to raise the groundwater level in the area of the Dujce fen which ranks among the qualifying habitats for determining the Natura 2000 areas, and thus restore appropriate conditions for sustaining this bog. The company TGM Bizjak, Dušan Bizjak s.p. completed the restoration works on approximately 500 m long section of upper stream and on 200 m in its lower part at the confluence with the Lipsenjščica stream.

Expected results of this restoration: A. slower runoff of low waters from the area of the intermittent lake, B. ground water level rise, C. retention of water in depressions and stream branches, consequently higher constant ground water level height and change in the soil – water rate.

Restoring Goriški Brežiček stream was planned for the entire section, from the mill at the source, to its mouth in Lipsenjščica River, but only a part has been realized. The entire length of the stream has been straightened in the past, but given the terrain and vegetation, the original stream channel is still clearly visible. Restoring the original layout consisted of its deepening. Average width of the planned channel section was from 3.0 to 6.0 m. Excavation has been exercised in the form of U, with banks sloping 1:2, but it was planned that the transition slope of stream bank and terrain on majority of the length is carried out in a vertical slope and then let the water itself create a stable bank. It was assumed that the stability would be provided primarily by turf and partly by the riparian vegetation root system. Deepening of the stream bed at the juncture with the primary bottom at the upstream side has been protected by the small wooden weir (a small weir with the top corners at the bed level or just above it, which is not noticeable under normal hydrological conditions). Where possible, multiple channels with lower spills/overflows between the excavated meanders were predicted. Spills/overflows has been fortified with small wooden weirs (wooden piles, tree trunks) to prevent uncontrolled deepening of the spills/overflows. Spills/overflows were carried out above medium water level and they were covered with turf. At the appropriate locations at the contact of the current and planned section have also been carried out coves or bays, which are designed by keeping part of the current channel or in the area of inactive tributaries.

                         RESTORATION OF THE TRESENEC STREAM:

The restoration of the former riverbed of Tresenec stream from its source in the direction of Levišča sinkholes was undertook in order to raise the level of groundwater and thus enable the sustenance of characteristic water and river-bank plant communities. The Tresenec stream is also of great importance to the animal world since it is the only watercourse in the Lake Cerknica area that never runs dry and as such offers refuge for the water animals in the times of drought. On its banks you can still find elusive Otter’s (Lutra lutra) footprints. GRADBINKO d.o.o. enterprise completed the restoration on 650 m long section of the Tresenec stream.

By increasing length of stream, restoring former branches and meanders, the water surface of stream increased, which will have a positive effect on the conservation of aquatic, riparian and wetland habitats.

Monitoring surveys and results

This case study hasn’t got any Monitoring survey and results, you can add some by editing the project overview.

Lessons learnt

This case study hasn’t got any lessons learnt, you can add some by editing the project overview.

Catchment and subcatchment

Select a catchment/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: HPP Blanca


Site

Edit site
Name
WFD water body codes SI141VT2
WFD (national) typology
WFD water body name VTJ Cerkniško jezero (Cerknica lake)
Pre-project morphology Straight
Reference morphology Sinuous
Desired post project morphology
Heavily modified water body No
National/international site designation
Local/regional site designations No, Ramsar, Special Protection Area
Protected species present No
Invasive species present No
Species of interest
Dominant hydrology Ephemeral, Quick run-off, we need to check
Dominant substrate Silt
River corridor land use Wetland, Extensive agriculture, Grassland, 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

Edit project background
Reach length directly affected (m)
Project started January/01/01
Works started
Works completed December/01/01
Project completed
Total cost category 2009 k€"2009 k€" is not in the list (Less than 1 k€, 1 - 10 k€, 10 - 50 k€, 50 - 100 k€, 100 - 500 k€, 500 - 1000 k€, 1000 - 5000 k€, 5000 - 10000 k€, more than 10000 k€) of allowed values for the "Total cost category" property.
Total cost (k€) 1000 - 5000 k€"-5000k€" is not declared as a valid unit of measurement for this property.
Benefit to cost ratio
Funding sources 1840

Cost for project phases

Phase cost category cost exact (k€) Lead organisation Contact forename Contact surname
Investigation and design Ministry of Environment and Spatial Planning k€"Ministry of Environment and Spatial Planning k€" is not in the list (Less than 1 k€, 1 - 10 k€, 10 - 50 k€, 50 - 100 k€, 100 - 500 k€, 500 - 1000 k€, 1000 - 5000 k€, 5000 - 10000 k€, more than 10000 k€) of allowed values for the "Investigation and design cost category" property.
Stakeholder engagement and communication
Works and works supervision
Post-project management and maintenance
Monitoring



Reasons for river restoration

Edit reasons for restoration
Mitigation of a pressure
Hydromorphology
Biology Quantity & dynamics of flow, Channel pattern/planform, Structure & condition of riparian zones
Physico-chemical
Other reasons for the project


Measures

Edit Measures
Structural measures
Bank/bed modifications changed bank slope
Floodplain / River corridor local deepenings, construction of small wooden weir to prevent uncontrolled deepening, coves and bays construction, construction of the overflows between individual meanders
Planform / Channel pattern retention of water in depressions and stream branches, ground water level rise, slower runoff of low waters
Other re-instatement of old course;
Non-structural measures
Management interventions late mowing and mulching on the permanently protected land, mapping of habitat types
Social measures (incl. engagement)
Other popularization of the project, Information provision, education of the youth on the importance of nature conservation


Monitoring

Hydromorphological quality elements

Edit Hydromorphological
quality elements
Element When monitored Type of monitoring Control site used Result
Before measures After measures Qualitative Quantitative
[[]]

Biological quality elements

Edit biological
quality elements
Element When monitored Type of monitoring Control site used Result
Before measures After measures Qualitative Quantitative
[[]]

Physico-chemical quality elements

Edit 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

Edit Other responses
Element When monitored Type of monitoring Control site used Result
Before measures After measures Qualitative Quantitative


Monitoring documents

Upload monitoring documents



Image gallery


Lake Cerknica in autumn (Photo: Notranjska Regional Park archive)
Restored old riverbed of the Tresenec (Photo: Notranjska Regional Park archive).
Tresenec in upper flow (Photo: Notranjska Regional Park archive).


Additional documents and videos

Upload additional documents


Additional links and references

Edit links and references
Link Description
http://archive-si.com/si/n/notranjski-park.si/2012-10-05 373223/ project archive

Supplementary Information

Edit Supplementary Information

REFERENCES

LAYMAN’S REPORT Project LIFE 06 NAT/SLO/000069, Intermittent Lake Cerknica, Notranjska Regional Park, Cerknica, december 2009. Availabe at: http://ec.europa.eu/environment/life/project/Projects/index.cfm?fuseaction=home.showFile&rep=file&fil=LIFE06_NAT_SI_000069_LAYMAN.pdf

Smolar-Žvanut N., Fazarinc R., Perič B., Blumauer S., Kavčič I. 2011. The restoration of tributaries of Cerknica Lake and Škocjan Caves Park. Seminar: Forging Targets and Solutions for Rivers and Water Ecosystem Restoration. Ljubljana, 16-18 November 2011.