Reservoir operation variations in Alpine catchments: a reconstruction using generalized additive models
Abstract
Reservoir regulation affects various streamflow characteristics from low over mean to high flows with important implications for downstream water users. Still, information on past reservoir operations is rarely publicly available and it is hardly known how reservoir storage and release signals vary in space depending on climate and catchment characteristics. Here, we develop a generalized additive modelling approach to reconstruct reservoir operation signals from observed streamflow time series that encompass a period before and a period after a known year of reservoir construction.
We apply this approach to reconstruct the seasonality of reservoir regulation, i.e. information on when water is stored in and released from a reservoir, from a dataset of 74 catchments in the Central Alps. Using these reconstructed regulation seasonalities, we identify groups of catchments with similar reservoir operation strategies using functional clustering. We find that reservoir management varies by catchment elevation and that seasonal redistribution from summer to winter is strongest in high-elevation catchments. These elevational differences suggest a clear relationship between reservoir operation and climate and catchment characteristics, which has practical implications. First, these elevational differences in reservoir regulation can and should be considered in hydrological model calibration. Furthermore, the reconstructed reservoir operation signals can be used to study the joint impact of climate change and reservoir operation on different streamflow signatures, including extreme events.- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2022
- Bibcode:
- 2022AGUFM.H13B..08B