Skurdalsåa flood retention

    Solution ID
    Description of solution
    Summary (Challenges; Objectives)

    The Skurdalsåa River is one of many steep tributary rivers to the main river Gudbrandsdalslågen. The river has its outlet from an old dam (1870) in Lake Svintjønna , high in the catchment, and it is ca. 7 km from the lake to its confluence with the main river. The total catchment is about 15 km2 , consisting of farmland, wetlands, small lakes, and mountain landscapes ranging in altitude from 200 to 1030 m asl. The catchment of the lake at 958 m asl. is only 3.2 km2. Due to the relatively small catchment, Skurdalsåa responds rapidly to precipitation and snow melt. Roads, houses, a school, a kindergarten, and a sports facility are situated adjacent to the lower part of the river. The infrastructure has experienced repeated flood damage in recent years.

    Through the H2020 project PHUSICOS an old dam has been modified in order to reduce the peak flood.

    Technical characteristics

    The implemented NBS has utilized the old dam (made of local stones, initially built for household water and irrigation purposes) to retain the flooding. The dam is modified by a modest increase of the dam height and lowering the discharge gate, and reinforcing the dam. The spillway is improved and extended. Hydrological calculations reveal that the proposed measures can retain and evenly distribute the peak flood for 48 hours (in a 200-year flood event).

    The ownership of the lake and the dam, are shared between 6 of the local farmers. The local farmers have carried out parts of the work, in addition to a local construction company.

    Success factors / lessons learnt

    Potential co-benefits:

    • increased sense of safety for the inhabitants along the river.
    • less potential for damage caused by floods to the valuable river environment
    • continued (and improved) the possibility of using the lake for irrigation purposes downstream.
    Limiting factors / lessons learnt

    Regulations are important to consider, and may cause project delays.

    Location Latitude
    61.5202000000
    Location Longitude
    9.8238100000
    Keywords
    Ecosystem (s) impacted
    Lakes
    Mountain
    Rivers
    Wetlands
    Hazard(s) concerned
    Floods
    Other challenges
    Climate adaptation
    Exposition
    Exposed assets
    Agriculture
    Urban or residential areas
    Strategic buildings (hospitals, schools)
    Roads
    Is there population exposed?
    Yes, low density of population (<50 persons /km2)
    Activity
    Are there jobs created in the nature-based sector?
    Yes, Less than 5
    Actors
    Organizations involved in the implementation of the action

    Through the H2020 project PHUSICOS an old dam has been modified in order to reduce the peak flood.

    The ownership of the lake and the dam, are shared between 6 of the local farmers. The local farmers have carried out parts of the work, in addition to a local construction company.

    Temporal aspects
    Design life time of the action
    More than 10 years
    Implementation time of the action
    Less than 2 years
    Others
    Is it possible to transpose this action in a different context?
    Yes, it is easily transposable
    Pictures
    Risk reduction
    Hazard
    +
    Exposure
    +
    Feasibility
    Environment
    Society
    Community involvement
    +
    Landscape Heritage
    +
    Economy