Exercise 2: Creating a Flood Situation Map of Larkana, Pakistan

Larkana flood response exercise track:

This exercise is the fourth part of the Larkana flood response exercise track.

The previous exercise can be found here

Competences covered in this exercise:

• Working with multiple layers

• Importing SVG libraries

• Using SVG markers

• Classifying Geodata

• Creating a print layout

• setting up overview maps

Estimated time demand for the exercise:

• The exercise takes around 3 hours to complete, depending on the number of participants and their familiarity with computer systems.

Relevant wiki articles:

• Visualisation of Vector Data

• Map Making

• Layer Concept

• Geodata Classification- Categorized

• Geodata Classification - Graduated

Context

In 2024, the provinces of Punjab, Sindh, and Balochistan in Pakistan experienced devastating floods due to intense and prolonged rainfall. You have already conducted an analysis utilizing actual data from this natural disaster in the previous exercise. We now want to visualize our findings on an appealing map that can be printed out or shared with different stakeholders. The map will show specific medical centers and healthcare facilities that where impacted by the flooding. Additionally, we will visualize the viability of road access to the city of Larkana throughout the flood period.

The exercise is split into two parts. In the first part, you will adjust the symbolisation of the layers for the final map. In the second part, you will use the print layout composer to create a finished map that can be printed and distributed.

Available Data

You have created the data for Larkana in Module 3 Exercise 5. In order to conduct this exercise please create a folder on your computer and copy your entire folder structure of Exercise 4 in there. In case you did not do Module 3 - Exercise 4 you can download the data here. Save the folder on your computer an unzip the file.

Dataset name	Original title	Publisher	Downloaded from
Flood_2024_AOI.gpkg	Subnational Administrative Boundaries	UN OCHA	HDX (This dataset has been modified in the previous exercise)
Health_Facilities_Flood_2024_AOI.gpkg	Pakistan Health Facilities (OpenStreetMap Export)	Humanitarian OpenStreetMap Team (HOT)	HDX
PAK_2024_Minimum_Flood_Extend_reprojected.gpkg	Satellite detected water extents from 08 to 12 August 2024 over Pakistan)	UNO SAT	HDX
PAK_flood_2024_blocked_road.gpkg	PAK_flood_2024_blocked_road	Yourself	This dataset was created in the previous exercise

Hint

Folder structure Keep your data management clean by creating a standard folder structure on your computer for your QGIS-projects and geodata.

Tasks

Preparing the data

1. Create a new QGIS-project and save it to your exercise folder. Give it a clear name, e.g. “Larkana_flood_response_map”.

2. In the Browser panel, Open the Project Home-folder and navigate to the data subfolder.

3. Import the layers in the folder and import the layers to your QGIS-project:

   • Healthsites: Health_Facilities_Flood_2024_AOI.gpkg

   • Roads: Roads_Larkana.gpkg

   • Blocked Roads Points: PAK_flood_2024_blocked_road.gpkg

   • Flood Extent 2024 reprojected: PAK_2024_Minimum_Flood_Extend_reprojected.gpkg

   • Administrative Boundaries for the Area of interest (AOI): Flood_2024_AOI.gpkg

4. Take a moment to familiarise yourself with the available data. Look into the attribute table of the different layers and look what information is available and how the attributes are named.

Adding symbols to your SVG-collection

While QGIS offers a variety of markers and SVG-symbols you can use in your maps by default, the selection of symbols is limited, especially if you work for organisations that have their own symbols, such as the Red Cross Movement.

5. We will use IFRC symbols in this exercise. We can import an SVG library into QGIS so we can access the IFRC-symbols QGIS.

   • Go to this website: https://learn-sims.org/style-guidance/logos-and-icons/

   • Under IFRC Icons, click on Download the full set here. You will be redirected to a dropbox folder with a zip-file containing all the IFRC icons in various formats.

   • In the top-right corner, click on download.

   • Download the IFRC symbols, unzip them and save them in a folder on your computer where you will find them again.

   • In the top bar of your QGIS-window, navigate to Settings > Options > System

   • In the field for SVG-paths, click on +-Symbol. A new window will open.

   • Navigate to the folder where you saved the SVG library. Click on Select Folder.

   • Now we will be able to access the additional SVG-files in the symbolisation window.

Part 1: Symbolization

Creating a good map involves selecting appropriate icons and colours to transmit the information in your data. The first step into creating a comprehensible map is to order the layers logically so you can see the information:

In the layers panel:

• Put the administrative boundaries layer at the bottom,

• put the roads and flood extent layers in the middle

• and put the point layers (healthsites and blocked roads)

Each layer has it’s own symbology panel where you can adjust the symbology, colours and labels for the features in that layer. Do you need to change some colours? Are the layers ordered in a way that the information is visible? Think about which data we need and what data we can leave out. For example, the layer Roads_Larkana contains too many roads for a map on a national scale. Let’s open the attribute table and look at how the roads are classified. The data is using the conventional OpenStreetMap classification: The type of road is described under the attribute highway. In our case, it might be useful to only display the primary and secondary roads, so all the features where highway=primary OR highway=secondary.

Let’s go through the layers one by one and visualize them in a meaningful way.

Healthsites:

In the layers panel, right click on the layer Health_Facilities_Flood_2024_AOI > Properties. A new window will open up with a vertical tab section on the left. Navigate to the Symbology tab. Let’s create our own customized symbol for healthcare facilities:

• Under Symbol layer type, select “SVG Marker”

• Scroll down to the SVG-Browser. Here you will find all the folders of your installed SVG-libraries.

• Scroll through the folder until you find a suitable symbol (e.g. ).

Create customized SVG Marker

We can customise the icon further:

• On the upper right corner of the symbology tab, click on the + to add another “Simple Marker”.

• By default, it will be a circle. Make sure the circle is below the -symbol by clicking on the

• Change the colour of the circle to white

• Click Apply, then OK.

You can use several symbol layers to create a complex symbol in QGIS 3.36

Roads:

The roads dataset contains a lot of information that we do not necessarily want to display on our final map. We can categorise the data and hide the unwanted information. To categorize the roads, double-click on the layer Roads_Larkana. The properties window will open with a vertical tab bar on the left. Navigate to the Symbology tab.

• On the top you find a dropdown menu. Open it and choose Categorized.

• Under Value select “highway”.

• Further down the window, click on Classify. Now you should see all unique values or attributes of the selected “Flood_affected” column. You can adjust the colours by double-clicking on one row in the central field.

• Remove the tick from all categories except: motorway, primary, secondary, trunk

  

  Classifying the roads: By unchecking the boxes you can hide the unnecessary information.

• You have the option to customize the width of the main roads’ lines to improve the visualization. Open the Symbology window, then select ‘Symbol’. In the new window, you can adjust the width of the lines to your preference.

  

  Classifying the roads: You can adjust the width of a single category.

• Once you are done, click Apply and OK to close the symbology window.

Blocked Roads Points:

Open the Symbology Tab for the PAK_flood_2024_blocked_road-layer and choose a meaningful symbol for flood related blocked roads.

Airports:

In the previous exercise you found out that the Mohenjodaro Airport in the southwest of Larkana City is still accessible via the road network. Essential supplies could potentially be transported from the airport into the city without encountering any roadblocks. We want to point out this possibility. Let’s mark the airport as a point and visualize it!

To do so we will create an entirely new point dataset representing airports.

• Click on Layer –> Create Layer -> New GeoPackage Layer(Wiki Video)

• Under Database click on and navigate to temp folder. Give the new dataset the name “PAK_airports”. Click Save.

• Geometry type: Select Point

• Under Additional dimension you should always make sure that you check None.

• Select the coordinate reference system (CRS) “EPSG:4326-WGS 84”. By default, the QGIS selects the project CRS.

• Under New Field you can add columns to the new layer. Add the column “Airport”.

• Type: Select Text Data

• Click on Add to Fields List to add the new column to the Fields List.

• Click OK.

• Your new layer will appear in the Layer Panel

  

  Creating a new point layer for the airports.

Tip

If you cannot see the toolbar View -> Toolbars and check Digitizing Toolbar (Wiki Video).

• Now you can create a point for the airport and if you would like additional airports as well wiki. Currently the new layer “PAK_airports” is empty. To add features we can use the Digitizing Toolbar.

• Once you have found the airport, click on it. Left-click on the feature you want to digitise.

• Once you click on a place, a window will appear. Indicate that the road is blocked by writing Yes in the field Blocked_road.

  

  Digitising new point features

• Once you are done with digitizing click on to save your edits.

• Click again on to end the editing mode.

In order to transmit the information quickly, we can use a plane icon to display the layer “PAK_airports”, instead of just a point.

• Right-click on the layer__“PAK_flood_2024_blocked_road”__in the Layer Panel -> Properties. A new window will open up with a vertical tab section on the left. Navigate to the Symbology tab.

• Keep the single symbol option. Select any symbol from the list that is appropriate for marking blocked roads.

• Once you are done, click Apply and OK to close the symbology window.

  

  Visualising blocked roads with icons

Flood Extent:

Open the Symbology Tab for the PAK_2024_Minimum_Flood_Extend_reprojected-layer. Choose a light-blue as color and adjust the opacity to about 30%.

Administrative Boundaries:

Open the Symbology Tab for the Flood_2024_AOI-layer. Click on Simple Fill and adjust the Symbol layer type to Simple Line. You can furthermore adjust now the outline colour and stroke width.

Bonus Step: Adding a basemap can help potential readers orienting themselves.

If you are happy with the symobolisation of your layers, the map should be ready for a print layout.

Attention

Remember the layer concept and place all layers in a logic order. The flood extents should lay under the roads and the several point layer above the roads.

Part 2: Creating the print layout

Once you are happy with the symbolization and colours of your data, the next step is to create a print layout. By adding additional information such as a title, data sources, projection, description, etc. you provide your audience with the means to contextualise and evaluate the map and it’s content by themselves.

1. Open a new print layout and give it a name (e.g. Larkana_floods).

   • Go to Project > New Print Layout > enter a name for the new print layout > click OK.

Creating a new print layout.

• A new window with a blank print layout will appear. This is the print layout composer.

  • On the left, you will find a toolbar with tools to add and move items on the print layout canvas.

  • On the right you will find a list of items you added to the print layout (it is still empty). Beneath this, you will find a tab called “item properties”. This is where you modify the items on your print layout (e.g. enter the text for a text box or change the font).

2. Insert a new map by clicking on (Add Map) on the left toolbar, and drawing a rectangle on the print canvas. Wiki Video

3. Move and position the map so that the area of interest is visible at a reasonable scale.

4. Let’s add a title:

   • Click on (Add text)

   • Drag a rectangle on the canvas

   • In the item properties window on the right, you will find a text box with the text “Lorem ipsum”. Here you can enter your map title (e.g. Larkama Flood Response 2024).

   • Adjust the font size: Click on the Font dropdown menu and adjust the font size for a title (25p or more). Adjust the text box if necessary.

5. Let’s add a legend:

   • Click on (Add legend).

   • Navigate to the Item Properties panel on the right.

   • Scroll down a bit and check turn off Auto Update by unchecking the check box. Now you can freely edit every item on the legend

   • Adjust the legend by removing unnecessary layers (which are not seen on the map) and rename the layer in the legend by clicking on (Edit selected item properties) below the legend entries.

   • Under the upper Main Properties, insert “Legend” as title

Using the print layout.

6. Now, let’s add a scale bar:

   • Click on (Add Scale bar)

   • Draw a rectangle on the map and position the scale bar on the edge of the map. You can adjust the scale bar units (meters, kilometers, …), the fixed segment width (50 km, 75 km, 100 km, …) and the number of segments (to the right).

7. Let’s add a north arrow:

   • Click on (Add North Arrow).

   • Drag a rectangle on the print layout. Adjust the size and location of the north arrow. You can also change the icon in the item properties.

8. Let’s add a logo (for example, your national society):

   • Click on (Add picture)

   • Drag a rectangle in the spot where you want to add the logo

   • Navigate to the Item properties panel on the right and switch to Raster image.

   • Click on the three dots ... and select the file with your logo

   • If necessary, resize or move the picture on the print layout.

9. Add some additional information as text.

   • Click on (Add text)

   • Drag a rectangle on the canvas

   • In the item properties window on the right, you will find a text box with the text “Lorem ipsum”. Here you can enter some additional information of the map, e.g. the coordinate system, basemap information or date.

When you are finished with your map design you can export your printable map as image or pdf under Layout–> Export as Image or Export as PDF

You could now have as a result a map similar to this one. Here, some space has been left in order to implement an overview map. If you are still have time go for the bonus exercise and add an overview map!

Your final map could look something like this.

Bonus Exercise!

If you are finished with the main map, click on the map and navigate to the item properties. In the layer section, check the box Lock Layers and Lock styles for layers. This means that if you change the map in the main QGIS-window, the first map you have added to the print layout will not be affected by these changes. Now you can start working on an overview map. We will be using a shapefile with the administrative boundaries of Pakistan.

1. Return to the main QGIS window and load the layers from the Bonus Exercise-folder. They include a polygon layer with the outlines of countries (alternatively, you can use the OSM basemap).

2. In the Layer panel, make the layers for the main map invisible by clicking on the next to the layer name.

3. Style the countries in an neutral, unobtrusive color. For example, you can use the “Gray 3 Fill” from the styling templates.

4. Once you are happy with the styling of your overview map, navigate back to the Print Layout window.

5. Add a second map and position it in a corner.

6. In the Item properties panel for the second Map (”Map 2”), scroll down and open the Overview-options.

7. Click on the +-button to add a new overview.

8. In the “Map Frame”-option, select “Map 1”. This will show the frame of the main map on your overview map.

9. You can add a scale bar and a northj arrow to your overview map as well.

The finished map could look something like this (Source: HeiGIT).

Congratulations! You have created a finished map that is ready to be printed and distributed.