A Dajia River tributary, Bi-Tan Creek, was hit by Typhoon Mindulle in 2004. A hydrological sand transport calculus model (CCHE2D) was used to simulate a 50-year-return-period rainfall scenario in the fourth phase of Bi-Tan Creek. The hydraulic sand transport before and after treatment was analyzed. Governance at the highest flow velocity in the lower reaches is reduced from 6.5 to 1.0 m/s, water storage depth increases from 1.7 to 3.5 m, and the water storage capacity increases by approximately 1,650 t. Energy dissipates sedimentation, and the storage capacity of the sedimentary area reaches 4,000 m3. The accumulation of soil and sand in front of the drainage tunnel decreases,
protecting normal operation of the drainage facilities.
Key Words: CCHE2D, Bi-Tan Creek, assessing effectiveness