topic Re: 5 to 100 year flood plain in Water Resources Questions https://community.esri.com/t5/water-resources-questions/5-to-100-year-flood-plain/m-p/589436#M3030 <HTML><HEAD></HEAD><BODY><SPAN>Hi Cadence,</SPAN><BR /><SPAN>You'll need good topographic data, good river profile data, good landuse data as well and a good hydrologist who knows how to use HEC-RAS (a 1-D modelling that has a plugin for ArcGIS called HEC-GeoRAS). Also, you will need historical rainfall data as the sorts of flood boundaries you're interested in are statistically calculated. Doing this for a whole country using these tools and data is a big task so you're probably better off starting with a small part of one major river system.</SPAN><BR /><SPAN>Hope this helps..</SPAN><BR /><SPAN>regards</SPAN><BR /><SPAN>Colin Constance</SPAN></BODY></HTML> Wed, 14 Dec 2011 04:34:28 GMT ColinConstance 2011-12-14T04:34:28Z 5 to 100 year flood plain https://community.esri.com/t5/water-resources-questions/5-to-100-year-flood-plain/m-p/589435#M3029 <HTML><HEAD></HEAD><BODY><SPAN>Hi,</SPAN><BR /><BR /><SPAN>I have DEM for my country (not usa), soils data, and water surface elevation as points. How do I generate flood plains to show 5 year flood plains, 10, 50 and 100 year flood boundaries?</SPAN></BODY></HTML> Fri, 15 Apr 2011 15:30:27 GMT https://community.esri.com/t5/water-resources-questions/5-to-100-year-flood-plain/m-p/589435#M3029 CadencePhillipe 2011-04-15T15:30:27Z Re: 5 to 100 year flood plain https://community.esri.com/t5/water-resources-questions/5-to-100-year-flood-plain/m-p/589436#M3030 <HTML><HEAD></HEAD><BODY><SPAN>Hi Cadence,</SPAN><BR /><SPAN>You'll need good topographic data, good river profile data, good landuse data as well and a good hydrologist who knows how to use HEC-RAS (a 1-D modelling that has a plugin for ArcGIS called HEC-GeoRAS). Also, you will need historical rainfall data as the sorts of flood boundaries you're interested in are statistically calculated. Doing this for a whole country using these tools and data is a big task so you're probably better off starting with a small part of one major river system.</SPAN><BR /><SPAN>Hope this helps..</SPAN><BR /><SPAN>regards</SPAN><BR /><SPAN>Colin Constance</SPAN></BODY></HTML> Wed, 14 Dec 2011 04:34:28 GMT https://community.esri.com/t5/water-resources-questions/5-to-100-year-flood-plain/m-p/589436#M3030 ColinConstance 2011-12-14T04:34:28Z