Starting a new RAS project is always exciting, possibly because my mistake counter is at 0. I am using HEC-RAS 6.4.1 since that is the latest version as of right now.
Project Naming
An end user should be able to get a general idea of the project from the file name. Any file (and folder) names) should not contain any spaces or special characters. Make use of underscores or CamelCase instead. Now there is a limit on the number of characters so be wary of names getting cut. I have named this project Caroni.prj
Switch the Units
Since we are not in the US, we need to switch the Units to Metric. Go to Options > Unit System. The main RAS window should now say SI Units in the bottom right corner.
Define the Projection
Before we create any geometry, we need to define the projection. This is done in RAS Mapper, which is HEC-RAS’s built-in GIS. Its not ready to put ESRI out of business, but it is getting more powerful with each iteration of RAS.
I like to create a folder called Projection and stick that in the model folder. In fact, any files that the model references should be located within the model folder. The projection for this project is WGS 1984 UTM Zone 20N since that sounds familiar to me. You can copy the projection file (.prj) from an existing shapefile that is in the correct projection and rename it projection.prj.
Open RAS Mapper and go to Project > Set Projection. Choose the projection file and ensure that it is correct before hitting OK.
Map Layers
Map layers are used for reference to add additional detail when creating geometry or viewing results. Right click on Map Layer > Add Web Imagery. There are several data sources to choose from. I like using Google Hybrid because of the labels. If the imagery does not show up, there may be an issue with the projection.
There is very good documentation for HEC-RAS that I encourage you to explore if you want to learn more. Now that we have a project set up with the basics. The next step is to Create a Terrain.
Mapping T&T 