ICM InfoWorks - 🌐 Surface Area Take-Off

 

🌐 Surface Area Take-Off

🌍 Overview

The Area Take-Off (ATO) option facilitates the auto-calculation of runoff surface areas and the contributing areas of subcatchments using GIS data.

📚 For a deeper dive into the theory, refer to the Area Take-Off Technical Note.

📋 Prerequisites for ATO

• Checked out model with included subcatchment areas 🔄
• Impermeable Area Survey (IAS) drawing 🗺️
• A coded, digitised map of the catchment's impermeable area for IAS 📍

🛠️ Incorporating IAS into Model

1. 📌 Go to Model menu > Select SubcatchmentArea take off.
2. 🖥️ This action prompts the Area Take Off Dialog.
3. 📤 Import the digitised GIS IAS data by:
   • Browsing for a GIS file 📁
   • Selecting a Layer in the GeoPlan View 🌏
   • Choosing polygons imported from GIS based on Category Field 🔄

🚀 Using the Area Take-Off Function

1. Click on the icon or opt for Grid windowsNew subcatchments window from the Window menu.
2. Open the Subcatchment Grid Window of the Subcatchments Grid 🔲.
3. Highlight the entire Contributing Areas column, then right-click on any selected cell.
4. Set the flag to #G (geo) via the FDlags option 🚩.
5. For updating specific subcatchments, follow these steps:
   • Select all subcatchments for the update 🔄.
   • Navigate to the Grid menu > Select Group network selections at top of grid.
   • In the Subcatchment Grid View, choose Contributing Areas column and pick the areas for the chosen subcatchments.
   • Alter the flag for the picked cells to #G (geo).
6. Access SubcatchmentArea take off from the Model menu 📌.
7. Indicate the source for the Impermeable Area Survey data, which could be:
   • A GIS file 📁
   • A layer in the GeoPlan Window 🌏
   • Previously imported polygons from the GIS file.
8. Opt for other settings as required. If you used the alternative method in step 5, tick the Update Selected Subcatchments Only box 📦.
9. Press OK to wrap up the process ✅.
10. For any issues during the Area Take Off procedure, always review the log file 📜.