Making a deep cut on the curb inlet has been used in some sponge-city (SPC) projects for road-bioretention stripes to manage stormwater runoff since they were easily implemented in the field. The efficiencies of the deep-cut curb inlets in those projects were unknown for lacking equation to evaluate their efficiencies. Two kinds of retrofit scenarios are commonly used: (1) The curb-cut cases when the deep cut is made only over the width of the curb inlet; (2) the road-curb cut cases when both the curb inlet and a small part of the road surface have a deep cut. An updated two-dimensional flow simulation program, FullSWOF-ZG, was used to determine two important parameters in road curb inlet design: The 100% interception curb inlet lengths (LT
) and the curb inlet efficiencies (Eci
). Eight-hundred retrofit modeling cases were compared with the no-cut cases to quantify the efficiency improvement of the deep-cut curb inlets. The simulation results show both LT
of the curb-cut cases do not improve much. This case study with limited combinations of longitudinal and cross slopes and inlet lengths demonstrated that Eci
of the road-curb cut cases improves to a large extent so that they can be used in the SPC projects and other urban drainage projects to reduce the flooding potentials. A general equation used to design and evaluate the road-curb cut inlets can be developed based on more simulation cases with a wide range of input parameters in a future study.
This is an open access article distributed under the Creative Commons Attribution License
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited