Converting a NEXRAD Rainfall Map into a Flood Inundation Map by ...

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software. Normally, the simulation of local projects composed of levees or similarstructures allows one to determine if the proposed structure protects against agiven design flow event as required by federal or local regulations. In particular,the levee certification process was traditionally driven by protection criteriaagainst river stage associated with the 1% chance flood (100 yr flood event) plus3 feet of freeboard. This conventional approach based on flood frequency analysiswas abandoned in the early 1990’s when the Corps of Engineers adopted riskanalysis techniques that replace the aforementioned “1% event plus freeboardstandard”. Besides having to consider the set of components that make up anoptimal solution some authors have tried to answer the question of optimal size ofalready selected projects.Multiple criteria can be used to define the “optimal” flood controlsolution. One alternative is represented by the economic efficiency of the project.The optimal sizing of flood damage reduction plans based on economic efficiencyhas been addressed by a combination of a simulation and an optimization models.Methods for optimal sizing of flood damage reduction plans based on economicefficiency have been reported (Wurbs, 1996). The method searches for anoptimum mitigation plan that may include non-structural measures. In theseoptimization approaches, the objective function is normally represented by theminimization of the total system cost and decision variables are represented by thesize of the structural components of the system.To develop a flood impact analysis system, flood related informationdescribing the spatial distribution of the floodplain is needed. GIS layers20
containing an inventory of damage sensitive facilities that belong to somecategory of land used (residential, educational, industrial, commercial, etc.) areobtained. Each of these damage sensitive components must have an associateddatabase that provides the attributes on which damage estimates can be calculatedusing economic methods such as benefit-cost analysis.2.4 PROPOSED CONTRIBUTIONS TO KNOWLEDGEThe idea of model integration has been described under various statementsas “bringing the models together”, “watershed in a box”, or “Regional WatershedModeling System”. As mentioned before, attempts to accomplish this modelingintegration have been reported in the literature which follows a step-wiseapproach in which the data is passed from one modeling program to another in amanual fashion favoring a time consuming and error-prone workflow that isfunctional but not very productive nor efficient. The GIS-based character of thereported attempts is represented only by the transfer of GIS-computedparameterizations to stand-alone modeling systems whose output is passed backto GIS for visualization purposes only. Thus, this step-wise integration based onlyon pre- and post-processing data exchange does not represent a true integration ofthe involved modeling systems.Process analysis/models represented by stand-alone simulation modelsmay synergistically employ the output of another simulation model and thus besequentially linked. To achieve the linkage, geographically oriented data modelscan be used to spatially associate the exchange of information from one processmodel to another. Once all the needed integrating elements are developed, a21
Page 3 and 4: Table of ContentsList of Figures ..
Page 5 and 6: 4.1.12 The XML2GDB Script Tool ....
Page 7 and 8: Figure 3.24 Components of a Steady
Page 9 and 10: Figure 4.50 Create Flood Inundation
Page 11 and 12: Chapter 1 Introduction1.1 BACKGROUN
Page 13 and 14: for undeveloped or natural conditio
Page 15 and 16: All the previous statements favor t
Page 17 and 18: science, and engineering models as
Page 19 and 20: Different approaches have been used
Page 21 and 22: generic and self-described formats,
Page 23 and 24: externally executed from a central
Page 25 and 26: though GIS-based, the system does n
Page 27 and 28: Geographic Information Systems, Arc
Page 29: By defining the three basic functio
Page 33 and 34: Data Models in charge of storing an
Page 35 and 36: Figure 3.1 Floodplain Modeling Sche
Page 37 and 38: either with Schematic Nodes (for Su
Page 39 and 40: channel cross sections, available H
Page 41 and 42: sequential data, called pathnames,
Page 43 and 44: Figure 3.5 NEXRAD square cells (873
Page 45 and 46: geodatabase formatted with the Arc
Page 47 and 48: The CrossSection feature class in A
Page 49 and 50: geodatabase (under Arc Hydro format
Page 51 and 52: 3.4.4 External Execution of HEC-RAS
Page 53 and 54: analysis. In particular, GIS has be
Page 55 and 56: 3.5.3 Model-Specific ElementsA geog
Page 57 and 58: Figure 3.11 Geographic and Hydrolog
Page 59 and 60: For HEC-RAS, the connectivity is ac
Page 61 and 62: cross sections in the hydraulic mod
Page 63 and 64: Section line for a RAS cross-sectio
Page 65 and 66: from the geodatabase back into the
Page 67 and 68: Figure 3.19 Relationship Classes fo
Page 69 and 70: Figure 3.20 DSS Time Series content
Page 71 and 72: Figure 3.22 Extended Time Series Co
Page 73 and 74: Figure 3.23 Creating a Flow File fr
Page 75 and 76: etween the HEC-DSS file system and
Page 77 and 78: The more specific steps for the pos
Page 79 and 80: Chapter 4 Map2Map Components4.1 MOD
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A subset of NEXRAD time series data
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A folder location is also provided
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Figure 4.4 Radar2GDB Model Componen
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ecords. Figure 4.6 illustrates the
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Figure 4.8 Time Series Tables and R
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having different formats and that a
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Part E: Time Interval of stored dat
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execution time and for their corres
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on the steps needed to transfer the
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Len_sBTime (I): The length of the s
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52: Invalid precision exponent spec
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methods: user hyetograph, user gage
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Once the hyetograph is defined (for
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The resulting runoff hydrograph is
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Thus, the time period for the entir
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After the ZSRTS subroutine is execu
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Figure 4.12 HMSCaller Model Compone
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ased on a process handle (a program
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These simple command line statement
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To programmatically accomplish this
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to provide the hydraulic input for
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information into the extended Arc H
Page 125 and 126:
The HydroJunction, used for connect
Page 127 and 128:
Once the identification of flow cha
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As with the GDB2HMSDSS, the first t
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4.1.7 Time Series ExtractionOnce th
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accomplish this have been developed
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straight forward for all time stamp
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As opposed to HEC-DSS, the Arc Hydr
Page 139 and 140:
Table 4.4: Variable Type Equivalenc
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ZCAT DSS subroutines) and stored in
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Table 4.5: Time Interval Equivalenc
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There are not specific valid values
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catalog list. For the DSS2GDB appli
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4.1.9.1 Opening the HEC-DSS fileThe
Page 151 and 152:
channel (the hydraulic representati
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the model if the new configuration
Page 155 and 156:
the main program as a public module
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Then, the RASCaller application acc
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Figure 4.31 ProjectName Property in
Page 161 and 162:
Figure 4.33 RunSteady Method in RAS
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Figure 4.34 ExportGIS Method in RAS
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data structures delivered by every
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The two most well-known models for
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The water surface elevations obtain
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Once the water surface elevations f
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Generate a suitable water surface m
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Figure 4.42 2 Foot-Contour Lines fo
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Figure 4.43 Rosillo Creek’s terra
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standard ArcGIS tool), is used in M
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By doing this, the water surface el
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Figure 4.49 Create Flood Polygon Mo
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Int OperationThe Integer operation
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case that was developed for Map2Map
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contours (isohyetals) or by interpo
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design storm input given its possib
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Figure 4.55 Workflow for Extracting
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for it. Finally, the DigitalStorm2H
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model for water resources (Maidment
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Hydro, the HydroJunctionHasCrossSec
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involved in the transformation of r
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process model in sequence. For the
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5.6 A TRUE SPATIAL APPROACHAutomate
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time series between NEXRAD, the HEC
Page 209 and 210:
value of the entire runoff hydrogra
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case study. Bigger watersheds (abov
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The first step consists in installi
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3.7 Map2Map UsageAll of the model b
Page 217 and 218:
Congratulations! You have successfu
Page 219 and 220:
Once the simplified version of Arc
Page 221 and 222:
cells that cover your study area an
Page 223 and 224:
Second, the user needs to modify th
Page 225 and 226:
Appendix BMap2Map CD Content1 CD Da
Page 227 and 228:
o hmsproj - contains folders with H
Page 229 and 230:
Goodchild, M.F., Steyaert, L.T., an
Page 231 and 232:
Olsen R. J., Beling, P. A., Lambert
Page 233 and 234:
Werner, M. G. F. 2001. Impact of gr
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