Development of HEC-GeoRAS ArcView extension

<body topmargin=0 leftmargin=0 marginheight=0 marginwidth=0> <table cellpadding=0 cellspacing=0 border=0><tr> <td valign="top" rowspan="2" width=185 BGCOLOR="#FFFFFF" TEXT="#080000"> <div> <A HREF="index.htm" TARGET="_top" TITLE="David Ford Consulting Engineers"><U><B><IMG SRC="0d058960.png" border=0 width="88" height="150" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></U></A></div> <bR> <div>    <FONT SIZE="1" COLOR="#000000" FACE="Verdana" > </FONT></div> <div> <B> <TABLE BORDER="0" CELLPADDING="4" CELLSPACING="1" WIDTH="156" BORDERCOLORLIGHT="#FFFFFF" BORDERCOLORDARK="#FFFFFF" FRAME="VOID" RULES="NONE" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=TOP HEIGHT= 27 WIDTH="146"><div> David Ford Consulting Engineers, Inc.</div> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 27 ><NOBR><div> 2015 J Street, Suite 200</div> <div> Sacramento, CA 95811</div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 27 WIDTH="146"><div> tel: 916.447.8779</div> <div> fax: 916.447.8780</div> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 27 WIDTH="146"><div> <A HREF="mailto:support@ford-consulting.com" TARGET="_top" TITLE="mailto:support@ford-consulting.com"><U>support@ford-consulting.com</U></A></div> </tD> </tR> </TABLE></B></div> <div>    </div> <bR> <div> <A HREF="index.htm" TARGET="_top" TITLE="David Ford Consulting Engineers"><U>Home</U></A></div> <div> <A HREF="id461.htm" TARGET="_top" TITLE="About us"><U>About us</U></A></div> <div> <A HREF="news.htm" TARGET="_top" TITLE="News"><U>News</U></A></div> <div> <A HREF="hydrologic_engineering.htm" TARGET="_top" TITLE="Hydrologic engineering"><U>Hydrologic engineering</U></A></div> <div> <A HREF="water_resource_planning.htm" TARGET="_top" TITLE="Water resource planning"><U>Water resource planning</U></A></div> <div> <A HREF="flood_economic_and_risk_analyses.htm" TARGET="_top" TITLE="Flood economic and risk analyses"><U>Flood economic/risk analyses</U></A></div> <div> <A HREF="flood_warning.htm" TARGET="_top" TITLE="Flood warning"><U>Flood warning</U></A></div> <div> <A HREF="decision_support_system_development.htm" TARGET="_top" TITLE="Decision support system development"><U>Decision support systems</U></A></div> <bR> </td> <td valign="top" colspan=2 height=40 BGCOLOR="#3366CC" TEXT="#080000" bgproperties="fixed" background="14400980ezthpx.png"> <div> <B>Development of HEC-GeoRAS ArcView extension</B></div> <div> </div> </td> </tr><tr> <td valign="top" height=440 colspan=2 BGCOLOR="#FFFFFF" TEXT="#080000" bgproperties="fixed" background="06c00962egerdp.png"> <div> <TABLE BORDER="0" CELLPADDING="2" CELLSPACING="1" WIDTH="547" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=TOP COLSPAN=3 BGCOLOR=#CC0000 HEIGHT= 16 WIDTH="537"><div> <B>Situation</B></div> </tD> </tR> <tR> <tD VALIGN=TOP COLSPAN=3 HEIGHT= 132 WIDTH="537"><div> The Corps of Engineers Hydrologic Engineering Center (HEC) River Analysis System computer model (HEC-RAS) is a one-dimensional steady river flow and water surface model. It has its own graphical user interface, but can export and import data to and from geographic information system (GIS) applications. HEC developed an ARC/INFO macro set to exploit this capability, and Environmental Systems Research Institute (ESRI) recently converted it to Avenue, a scripting language that operates within ArcView. The resulting product is an extension for ArcView called HEC-GeoRAS.</div> </tD> </tR> <tR> <tD VALIGN=TOP COLSPAN=3 BGCOLOR=#339933 HEIGHT= 16 WIDTH="537"><div> <B>Action</B></div> </tD> </tR> <tR> <tD VALIGN=TOP COLSPAN=3 HEIGHT= 768 WIDTH="537"><div> We have worked closely with HEC staff and assisted them in a series of projects intended to improve significantly the extension so that it functions in a robust, user-friendly manner.</div> <div> We developed advanced Avenue scripts, menus, and dialogs to extract land-use data, cross-reference these to Manning's n values, and publish these in the HEC-RAS geometric import file format. Manning's n values are used by HEC-RAS to calculate frictional energy losses when computing water surface profiles. Adding the capability to estimate Manning's n values from GIS layers will facilitate analysis of discharge data for the production of digital maps showing limits of inundation.</div> <div> HEC-RAS calculates runoff velocities at points along each river cross section. Within a GIS, other data can be combined with this velocity distribution, using three-dimensional graphics, in a form that assists in analysis of bank protection projects and sedimentation studies. We developed Avenue scripts that create surfaces (TIN) and raster layers (grid) from velocities exported from HEC-RAS.</div> <div> We also added capabilities to GeoRAS to enable this extension to identify properly floodplain areas that are protected by levees, thus improving the inundated-area mapping capabilities of GeoRAS.</div> <div> Using the fully integrated HEC-GeoRAS ArcView extension that we have provided, users spend less time preparing input to and analyzing output from HEC-RAS. They also make fewer mistakes when using HEC-RAS, as the extension automates some of the more tedious tasks.</div> <div> <IMG SRC="26de07d0.png" border=0 width="480" height="381" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </tD> </tR> </TABLE></div> <bR> <bR> <div>  </div> <bR> </td> </tr></table></body>