Modeling Sediment Load in Storm Drain System of Southeast Texas Coastal Region

Abstract

Sedimentation in a drain system has been recognized as one of the major causes of nuisance flooding produced by localized storms in Southeast Texas. The objective of the study is to assess the sediment load from runoff under different hydrological and road conditions to implement design guidance for a proper self-cleaning drain system. A diffusion wave model is developed to simulate runoff hydrodynamics on the roadway with curb inlets. An empirical sediment load equation is developed as a function of rainfall intensities, road conditions, and field sediment characteristics. The required flow velocity to erode the cohesive deposited sediment, and transport the deposited sediment incorporating the sediment from runoff in the drainpipe has been investigated to implement design guidance for a self-cleaning drain system. Regional hydrological conditions and field sediment characteristics are critical to design an effective drainage system for improving coastal resilience under severe weather conditions.