The Development And Servicing Of Spatial Data Management Techniques In The Corps Of Engineers

The U.S. Army Corps of Engineers is using spatial data management techniques in studies that are structured in a manner that requires spatial data management techniques to play a central and dominant role. The Corps of Hydrologic Engineering Center (HEC) provided the basic developmental work on the spatial data management and attendant processing techniques and it is continuing in the role of the basic technology transfer agent. The significant efforts required to document, maintain and service the technology and provide ready consultation service reported herein were planned for during the developmental efforts and are currently being centrally managed to encourage smooth adoption of the techniques by Corps field offices. (Author).

"The Corps of Engineers Hydrologic Engineering Center has developed techniques that perform the spatial data analysis approach and individual structure approach and work is near completion on an integrated analysis package. The capability therefore exists to perform damage appraisals in a manner that encourages a general geographic and land use approach (thus greatly facilitating the study of nonstructural measures) while preserving the ability to analyze individual, unique structures should the need arise. This paper discusses the basic concepts of a spatial data management approach to damage appraisals and highlight(s) its integrated use with more traditional individual structure approaches. Selected example results are presented"--Page 2

Computer program HEC-1, a precipitation-runoff model widely used throughout the United States, includes the capability to estimate automatically any of twelve parameters necessary to model the precipitation-runoff process and the channel routing process. The parameter estimation scheme employs Newton's method to minimize a weighted sum of squares of differences between observed and computed hydrograph values. Applications of this parameter estimation procedure are presneted, and typical steps of the procedure for deterimining optimal parameter estimates are outlined. Recent efforts to improve the estimation algorithm and recent use of the calibration capability to update sequentially parameter estimates in a flood forecasting application are discussed. (Author).

This technical paper presents a general overview of the Corps of Engineers' past involvements, present practices, and the future roles in dealing with alluvial fan flooding problems. The Corps' approach to alluvial fan flooding studies and the analytical methods they use to assess potential flood hazards are summarized. Selected case studies are presented. Six important issues that need to be considered as part of an effective alluvial fan management approach are presented. An extensive list of references is also included. (fr).