3.1. Combining Map Data

And the roads which is asphalt roads which having the low risk and gravel roads and unpaved roads which are more into the high risk. That is how the categorization of the built environment into 3 vulnerable classes.

This chunk explains how roads are categorized into different risk classes. It states that asphalt roads are considered low risk, while gravel and unpaved roads are categorized as high risk. This classification is important for understanding which areas are more vulnerable to hazards.

Imagine a city where main highways are well maintained and designed to withstand heavy rain, while dirt paths leading to rural homes often flood easily. In this case, the highways are like asphalt roads (low risk), whereas those dirt paths are similar to gravel or unpaved roads (high risk) in the context of their vulnerability to damage.

And then coming to the social approach, what they did was they divided into 8 sectors the whole region into the eight sectors like you can see the River Delta which is forming out and the whole heritage properties about here. And that what they did was they divided this whole territory residential territory into 8 sectors and the community representatives from each sector formed the group to accomplish the group mapping exercise.

This section discusses the strategy of dividing the area into eight sectors for a more organized assessment of risks. By involving community representatives in each sector, they conducted a group mapping exercise to gather essential data. This collaborative approach ensures that local knowledge is incorporated into mapping efforts.

Think of a classroom where a teacher divides students into groups based on different topics. Each group contributes their knowledge to create a comprehensive project. Similarly, the community representatives contribute their insights about their respective areas, making the mapping effort more robust and comprehensive.

So the biggest difficulty here is comparing the two maps because of the spatial data format one is the traditional flood risk map uses the one-meter raster grid cells, whereas the risk perception map is based on the polygons of varying sizes.

Here, the text highlights a significant challenge in comparing two types of maps: the traditional flood risk map and the risk perception map. The traditional map uses a grid system, while the perception map uses polygons, making it difficult to overlay or compare the two accurately.

Imagine trying to fit a square puzzle piece into a round hole. It just won't work. Similarly, the different formats of these two maps make it challenging to directly compare the data they represent.

When this is the flood hazard map of the extreme and there is given the threshold values of 0.5 to 1.5 meter depth of inundation there is inundation map and if you can see that this whole region is completely flooded right about 1.5 meter height of inundation.

This chunk introduces the concept of a flood hazard map that indicates the extent of flooding based on certain thresholds of water depth. The mention of values between 0.5 and 1.5 meters indicates varying degrees of concern, with areas flooded at 1.5 meters requiring urgent attention.

Think of how a weather report shows forecasts for different levels of rainfall. Just like how we might worry more if rain is expected to reach 2 inches instead of just 0.2 inches, the flood hazard map provides insights into each level of risk based on the depth of water.

So that is how what they did was they tried to classify different layers of it and like physical vulnerability now when you talk about the physical vulnerability what are the places which has been in highly damaged, medium damaged, and the low damaged and which has been not defined.

In this section, the focus is on mapping various types of vulnerabilities, including physical damage levels. Areas are categorized into high, medium, and low damage classifications, which helps to identify which locations require more resources for recovery and rebuilding.

Consider a school after a storm – some classrooms might have minor leaks (low damage), while others have major structural damage (high damage). This classification helps teachers prioritize which classrooms need immediate repairs, similar to how vulnerability maps direct recovery efforts.

And you can see that you know much of the cultural properties are under the high risk. And this is where one has to understand that the heritage which is UNESCO world heritage it is subject to the high risk.

This part emphasizes the high risk faced by cultural and heritage sites, particularly those recognized by UNESCO. The loss or damage to these sites not only affects current communities but also deprives future generations of their heritage and history.

Imagine a treasured family heirloom passed down for generations. If something were to happen to it, that loss would be felt by future family members. Similarly, the damage to cultural heritage sites poses a threat to collective identity and history.

Now what they did was they tried to combine this map and one is using all the digital tools how they combined and this is again a combined flood risk map by a traditional approach.

This chunk describes the process of combining various mapping approaches, including traditional methods and digital tools. By integrating different data sources, planners aim to create a more comprehensive flood risk map that considers multiple perspectives.

Think about a chef who incorporates various ingredients into a dish—combining flavors from spices, herbs, and proteins. Just like how these diverse ingredients create a richer meal, merging different data sources can produce a more complete map that represents the flood risks more accurately.

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