Author(s): Marko Ojamaa; Abolfazl Jalali Shahrood; Ali Torabi Haghighi
Linked Author(s):
Keywords: Ice jam; Floodgate operation; HEC-RAS; River ice
Abstract: This study investigates the impact of altering floodgate operations on water levels in the River Kyronjoki, focusing on the influence of river ice during varying discharge scenarios. The study considers 50-, 100-, and 250-year floods in open-water, ice cover, and ice jam conditions. The current practice directs the opening of floodgates when the Nikkola gauging station's water level reaches N2000 +40.53 m to prevent flood damage to upstream town of Ilmajoki and downstream communities. However, this releases floods onto arable land, causing agricultural problems. The research explores the possibility of delaying floodgate opening to mitigate agricultural harm, balancing the need for flood prevention with agricultural concerns. Using HEC-RAS we modelled different flood scenarios, assuming floods occur during spring break-up. The results indicate that modifying floodgate operations has impacts on water levels, suggesting potential flexibility in future permit adjustments. These findings offer solutions for policymakers considering alterations to the current permit, emphasizing the importance of balancing flood risk and agricultural interests in river management.
Year: 2024