Intro to HEC-RAS: Uploading terrain

hi everyone welcome to my channel which is just about geospatial references and environmental engineering and how that relates to climate and climate justice so today i'm going to show you and discuss how to create and set up a 1d hacras model just the basics into the terrain and explaining all about how we can get started together so first i'm going to share my screen and the first thing i'm going to do is google the national map by usgs so search the usgs national map download and it should be like pretty much the first thing that comes up and so once you have this i would like you to type in the area that you're interested in so i'm really interested in holyoke and the connecticut river and so i'm going to zoom out to about this extent and from here what i would like to do is download some of the elevation source data so you don't have that i would also be interested in the elevation products so click the things that you would like so i wanted the elevation source data and i also wanted to see if there was elevation products and if they have that data it will show it to you so i just clicked search products now what came up it's a little hard to understand so what i'm going to do is i'm going to click on show all thumbnails and then this will show us what our map will look like kind of in like real time and once i click on show more um it's a little bit dark and kind of hard to see so if this happens i would kind of click on the thumbnail see if it's like appropriate to you and if it is zoom to it and see if it is appropriate so this is not really appropriate to us so i'm actually going to go back to the datasets and then i'm going to uncheck the elevation source data and i'm only going to click on the geotiff format of the one-third arcsecond dem or maybe i'll do one meter video that would actually make more sense and then i'll search the products again and i'll see if they come up for where i'm interested in okay so again i'm interested in holy oak okay so this is for connecticut i'm going to search the products again the area i want it might take a couple iterations to see exactly what you want um so i think this is like a bit unusual on how the color and the extent is but let me grab the one that highlights the area i want so as you can see it's filling out the area based off of the thumbnail so it's this kind of grayish area and so what i'll do is i'll download the link and the link is just called the tif and so i have created this folder in my documents called heck data and i'll go in hecras and i'm going to download this into my example projects but one thing that i think would actually be the most helpful is to create a complete folder with this exact file set up and so i have the gis files hydrology files a projection folder results shapefiles in terrain and so if i go to terrain we can see the type of terrain that i've downloaded here and so this is the terrain that i've downloaded here the one that i have previously is the one usgs arc second dem and so i think i might use that instead and so i'm gonna click on the one third part second and then we'll see what comes up yeah this one will probably look better okay so i'm downloading the link again i've put it into my file folder yep this is the exact same data that i had so i'll put it in my terrain file yeah it'll just come out as a little paintbrush image but that's just a placeholder okay so the next thing that we're going to do is we're going to search for massachusetts projection data so the website that i like to use is called spatialreference.org and what i have here is the massachusetts inland data and so yeah this is the massachusetts mainland data the nad 83 and so i have it downloaded right here as a dot prj file don't get this confused with your hecrass.prj file as well and so i'm going to do the same thing i'm going to save this into my projection folder so i have heckross holyoke this is my projection folder and i have it right here okay so now we can get started on the actual grass where so the first thing i'm going to do is search it up in my file drive and then get it started and i'm going to call this new project my tech test and then make sure you save it into your specific folder so i've had press holyoke and i have all my other test files right here i'll just call this heck test or i can just call it like backtest2 so now here we have our heck test2 you can open the geometry in a bunch of different ways but we're going to do that in our second or third video the first thing that we're going to do in this one is click on the unit system and we're going to create it in the metric system or in the si system you can set the default for new projects so i'll do that and the next thing we're going to do is open raznapper which is this map shaper okay so we've opened res mapper it's opened on my second screen and so once we have raz mapper open the first thing that we're going to want to do is upload our terrain so you'll click on create a new rast string and you'll click this plus symbol once that's open upload the data that you had and so i'll call this terrain test terrain too or something oh i already have this redo okay so i have it as test terrain too and now what i'll do is you'll click on create so it already exists so i won't run it again but once you do that you can create or upload the same terrain by add existing grass terrain and so that's what i'm going to do right here so i had this already existing terrain i noticed the oak river because we saw and did it together and the next thing i'm going to do is i'm going to add some web imagery so that we can get oriented and see where we are in the space so this is google satellite and i'm going to upload the google satellite and you see how it kind of just dominates the rest of the image so what i'm going to do is i'm going to click on the layer properties and i'm going to put it at about 50 opaqueness so with that you can kind of see a little bit more and then what i'm going to do is i'm going to zoom into my specific extent that i was really interested in i was interested in this reach that goes from about north amherst down to holyoke which is about from right here right here and how i know that is i looked at the google earth imagery and i figured out one just super defining feature of the landscape and one was this airport right here so i know that with that i'm pretty oriented and so here we have it once we're done with this we just save it and we'll be able to come back to it anytime we want so i hope that was a good intro next time we work together we're going to work on creating the specific extent to this and figuring out how to troubleshoot with 1d flood hazard wrapping so thanks again for coming to the first video i hope you enjoy the rest of the series

Channel: Cielo Sharkus

Views: 2,877

Keywords:

Id: d81tDYRpp0U

Length: 7min 44sec (464 seconds)

Published: Wed Sep 01 2021