This video explains how to set up your model for watershed analysis, as well as figuring out how much your analysis is going to cost in Cloud Credits.
- [Instructor] The model I've chosen here is in North Carolina. Orange County, North Carolina. Near to Hillsborough, so Hillsborough is somewhere over here I think and the reason I chose it, it's because it's fairly intuitive. You can see you've got some higher points and some lower points. So let's have a look over here. And you can see, where you've got run-off areas, you've got streams, so they're quite intuitive and it'll be easier for us to figure out how the terrain is going to effect the way in which water behaves.
So, before we start you don't have to do anything here just follow along with me. What we have here is a model in which I have Imperial unit configuration. I did switch the area from square feet to square miles just because what we're doing is we're looking at quite large areas and it's much easier to figure out whether something is 10 square miles rather than 14000 square feet or something like that so that's what I did.
If you don't like it you can change it back. What I did was I went to the options and then chose application options and it's under unit configuration. And even if you were to choose Metric as the default units, you could still have Imperial inches, feet, yards, those types of things in your different unit defaults. So length, area, volume, those types of things. So that's number one. Otherwise, there's no real prep needed for watershed drainage analysis other than figuring out what method do you want to use and the values you are going to use.
So, I'm going to click on this watershed that is here in my model already and you'll notice that we have geometry, elevations and hydrology methods. Now what we're going to need is a number of different things so we've got what they call annual peak flow and this is what we call the hundred year storm, the 50 year storm and the 10 year storm.
Now despite the confusing nomenclature, a hundred year storm is not a storm that occurs every 100 years. It is a storm that has a 1% probability of occurring in any given year. Not of occurring once in every hundred years. So equally 10 year storms have a 10% chance of occurring in given year and a 50 year storm has a 2% chance of occurring in any given year. So just bear that in mind when we talk about things like the 10 year storm, the hundred year storm, the 50 year storm.
These are not probabilities that will happen every hundred years, these are probabilities that will happen in any given year. So these values that we're looking at over here they can be found on the design standards of many local authorities and city authorities. For example, just Google design storm for your area and you'll be amazed at type of information you can come up with. The internet is wonderful, it's not just for cat videos. So the other thing that you need to remember when you're using watershed and drainage analysis is that you are most likely going to be using Cloud Credits, and what we have here is the ability to look at Cloud Credits and you can go to the subscription center to find out how many Cloud Credits you have.
Now I'm working with any InfraWorks trial over here and the reason I'm doing this is because I want you to be able to do the same things that I'm doing. When you get a free trial, you get 100 Cloud Credits and some of these analyses that we're doing require 50 Cloud Credits for a five kilometer running section of road. So they're not cheap when you consider that Cloud Credits cost about a dollar, or a euro, or a pound each.
So we're talking about £50 or $50 to do these analyses so this at least is a way of figuring out whether or not this is something that you want to do and learn, without either spending a fortune on Cloud Credits or burning through your organizations Cloud Credits. So with that let's get started and do some hydrology terms and methods.
- Hydrology terms and methods
- Analyzing a watershed
- Troubleshooting your model
- Modifying culverts
- Culvert reporting
- Adding a drainage network to a model
- Analyzing and inspecting elements of a drainage network
- Sizing a drainage network