Small reservoirs, as the preferred blue-green engineering infrastructure for use against intensive runoff processes, have risen in number in Central Europe during the past three decades. However, the ...modelling of sediment siltation is not included in reservoir planning. The unknown temporal sedimentation of a reservoir can lead to the lifespan of the construction being uncertain. The aim of this study is to present a relatively simple process for local managers to model siltation and, consequently, accurately estimate the lifetime of a small reservoir. Three empirical models (USLE, RUSLE and USPED) were applied to two small catchments in Central Europe. This paper takes advantage of real measured and modelled sedimentation during 2012 and 2017, presenting two different terrain measurement approaches. Our study emphasizes the importance of the R-factor value. The temporal development of the R-factor is dependent on climate change, and the R-factor value has been rising steadily during the last decades. The annual mean R-factor has increased 1.04-times due to changes in precipitation patterns between the periods 1961–1980 and 1997–2016. These changes can explain possible growth in the levels of incoming sediment into reservoirs. We identified the correlation (R > 0.7) between observed sedimentation, the R-factor, and precipitation, and we concluded that the supposed rise of precipitation in Central Europe due to climate change will lead to an increase in the levels of stored sediment in reservoirs. Therefore, it is recommended for reservoir managers to use USPED model and to include the estimation of modelling of siltation rate into reservoirs’ maintenance projects.
•The USPED erosion model is suitable for the assessment of reservoir siltation rate.•The infilling process in small reservoirs is relatively slow.•The current rate of climate change potentiates erosion processes.•The R-factor is rising, with significant disturbances in year-on-year comparisons.
The "Dynamic SlowDown" concept (noted hereafter "DSD") promotes flood mitigation by slowing down, using transverse obstacles or temporary storage works distributed throughout the catchment. In ...accordance with Sustainable Development, it aims at reducing the use of the flood defence structures that damage riverine ecosystems. DSD hydraulic projects must be planned at catchment scale and must take all the problems into account, including ecological issues.
Cemagref and Cracow Institute of Water Engineering carried out a DSD feasibility study in a small mountainous catchment in Poland, the Isepnica catchment. To deal with flood and erosion problems, they proposed small storage works on hillslopes and a dry reservoir. To assess their impact on design floods, they developed two simple distributed hydrologic models, and linked them with a hydraulic model built for the main torrent. They concluded that the proposed strategy was efficient. In a further stage, it is envisaged to build and monitor pilot structures, in order to check their behaviour, better calibrate the models, and issue maintenance requirements.
PDF