Introduction Culverts, one of the most popular crossing hydraulic structures, are mainly constructed to facilitate the waterway flowing below their roads or railways’ intersecting locations. However, their functional operation usually led to water flow passage limitation and therefore blockage occurs due to the accumulation of debris at their inlets. Consequently, this blockage can cause culvert bed scouring and failure. Methods In this context, this study involved determining the culvert scouring pattern. Therefore, a distinctive laboratory experimental program in both non-blocked and partially blocked conditions was implemented to investigate the dominant parameters that affect the culvert’s scour depth formation. Results The study proved that the culvert governing geometry, flow condition, and blockage percent are mainly considered the dominant parameters in studying and estimating the scouring at the outlet of the culverts. In addition, a new proposed design formula for defining the local scour depth has been developed. Conclusion The proposed formula for scour depth determination was statistically compared with the previously developed models and it was showing a successful agreement with them.