Water Resources Research Act Program

Details for Project ID 2020UT305B

Improving the Hydraulics of Urban Flooding

Institute: Utah
Year Established: 2020 Start Date: 2020-03-01 End Date: 2021-02-28
Total Federal Funds: $30,000 Total Non-Federal Funds: $49,750

Principal Investigators: Zachary B. Sharp

Abstract: With ever changing weather patterns, flooding continues to be prevalent. This is not just true near coasts where record flooding has occurred from hurricanes Harvey and Florence in recent years. Flooding also occurs inland and often times in rural and urban areas, with both people and property affected. The development of tools to predict both the possibility and extent of flooding is a continuing effort both on coastlines and inland. These tools are improving and can be used to forecast flooding before it happens, which may lead to preventative measures such as placing sand bags or other flood barriers or evacuating certain urban areas. One area of improvement is the potential for better topography and bathymetry data of river and stream channels and also flood plains. One potential weakness in these tools is the use of 1-dimensional (1D) hydraulics to route storms. 1D routing methods can be sufficient, but with poor terrain data large errors can exist. To address this issue, a case study of the Logan River is proposed. This river has a history of urban flooding issues in the spring. The primary water supply is snowmelt, with spring rains adding to the already large flows. In coordination with Logan City to identify locations of interest, improved hydraulic models will be developed. Some of these locations could be stretches of the river channel or small hydraulic structures. The following steps will take place to assess the sensitivity of the river flood routing. Step one will include investigating different methods of acquiring more accurate terrain data. It is anticipated that LiDAR data and aerial photography will be used to improve the topography and bathymetry data. Step two will be to test the sensitivity of the 1D model to more detailed channel geometries. Step three will be to compare the 1D model to a 2D model and finally a fully 3D computational Fluid Dynamics model.