Simulation of the impact of restoration of the Jordan meander on the Orlice river on the regime of the adjacent Quaternary sediments

A very urgent challenge for water management organizations in the Czech Republic is the issue of water retention in the landscape. One of the initiatives of Labe River Water Authority is the restoration of the Jordan meander on the Orlice River. The project is running between 2019 and 2021 within TGM WRI internal grant support.

Project background and aims

The return of the watercourse into its original riverbed, as well as technical intervention that will raise the water level to the original level, are significant interventions in the water regime. The positive impact will be felt in the event of both climate extremes – floods and droughts. The immediate impact will be a slowdown in surface water runoff; however, simultaneously, the increase in the Orlice water level will be reflected in more intensive bank infiltration in the initial phase of restoration.

Project methodology

At the end of 2018, on behalf of the Ministry of the Environment, TGM WRI started monitoring the state of the groundwater regime in the adjacent Quaternary sediments before the start of restoration measures. The groundwater level is continuously measured at four newly drilled wells. A mathematical model was built from the measured data which simulates the expected impact of restoration on groundwater resources. Simulations of the current state and the state after restoration were prepared with an increase in the water level in the meander by 1 m and by 2 m. Based on the model results, the increase in the groundwater supply in the Quaternary collector was calculated.