Effects of the design flood share of the Kyeongpo retarding basin, which has a function for flood control of the
Kyeongpo river assigned to the Kyeongpo prickly water lily wetland, on the Kyeongpo lake and the downstream of
Kyeongpo river were analyzed on the bassis of the hydraulic experiments and the numerical simulations using
RMA-2 model. Reproducing a complex water flow system of the area of Kyeongpo lake, the unsteady flow
simulations were performed. The data obtained in hydraulic experiments were used to determine parameters of the
numerical model which simulated the flows for various flood scenarios in the downstream area of Kyeongpo river.
With increasing the design flood share rates in the retarding basin, the water level was increased in the lake and is
decreased in the river. The characteristics of flood flow interaction between Kyeongpo river and Kyeongpo lake were
understood. These results may be used to management the Kyeongpo lake during flood season.