Case 2: Susquehanna River (Pennsylvania) and San Antonio River (Texas)

		The Hydrologic Engineering Center of the US Army Corps of Engineers has developed a flood early warning and response system along approximately 177 kilometers (110 miles) of the Susquehanna River in northeast Pennsylvania, and on 161 kilometers (100 miles) along the San Antonio River and on 64 kilometers (40 miles) of the Cibilo River, a tributary of the San Antonio River. The purpose of developing these EWSs is to provide the residents of the affected areas and the appropriate emergency agencies with timely and precise warnings to allow them to maximize the use of the time available to implement the emergency plans in force for these circumstances, and therefore, benefitting the residents of the flood plains of the Susquehanna, San Antonio and Cibilo rivers. Both EWSs incorporate aerial photography, land elevation data,

geometry of the river beds, demographic information, land based communications, inventory and economic evaluation of the structures located in areas that could possibly be affected, with a hydraulic model that creates an interactive flood map based on a Geographic Information System.  The HEC-RAS was used to develop a hydraulic model for the whole project area. Multiple flood simulations were developed and referenced in the land elevation model. The operational quality of the EWS implemented in the Susquehanna River is based on four telemetry stations, located in the project area, that record river levels. These stations are operated by the National Weather Service.

Three telemetry stations installed in the San Antonio River record river levels (two in the San Antonio and one in the Cibilo River). A level known or estimated by the National Weather Service at one or more of the measuring stations makes it possible to identify the flood area and thus determine the infrastructure that may be affected and the amount of damage that can be expected.

The timely estimate of the severity of the floods will help emergency management staff to identify at-risk areas and to devise evacuation plans. It will also allow owners of affected property to minimize potential damages. Furthermore, preliminary damage estimates can be provided to the Federal Emergency Management Agency either before or while the event is taking place in order to provide timely assistance to the individuals affected.

Both are centralized flood warning and response systems.

Presenter

• Cameron Ackerman


Documents

• Presentation on The Development of a Flood Warning and Response System

• Early warning and resilience capacity to floods - The Susquehanna & San Antonio River


Cases

• Case 1: Floods in the Río Cabra Basin

• Case 2: Susquehanna River (Pennsylvania) and San Antonio River (Texas)

• Case 3: An Early Warning System