Flood Modelling & Analysis

Flood Analysis

Floods are a phenomenon with significant socio-economic implications, for which many researchers try to identify the most appropriate methodologies to analyze their temporal and spatial development. Flood Impact Analysis can be used to develop localized flooding scenarios and visualize the impact of flooding on public infrastructure, critical facilities, and vulnerable populations.

The solution allows you to understand and visualize the impact of flooding on the community by using flood depth and elevation data to analyses the impact of river flooding, storm surge, tidal surge, and sea level rise scenarios. The results of the analysis can be used to plan road closures, prioritize evacuation areas, and develop mitigation strategies. Flood Impact Analysis is typically implemented by emergency management, public works, and planning organizations that want to prepare for future flooding to protect their communities.

Flood modelling

As far as prevention goes, there’s not a whole lot that can be done to stop floods from occurring. Rain is going to fall whether we want it to or not, and floods are important for many ecosystems. What we can do is reduce the impact of floods when they occur. The best way to do that is to build our cities and towns to be safer during floods. To do that, we need accurate flood modelling.

Flood modelling is a cost-effective tool for informing all aspects of floodplain management. Flood mitigation assessments, land use planning controls, infrastructure design and even flood insurance classifications are all directly impacted by the precision and accuracy of the flood modelling on which they are based.

Flood modelling is a pretty big and complicated field, but one important piece of data that is needed for accurate modelling is high quality elevation data. Drone mapping and photogrammetry can provide finer resolution elevation data than can be achieved through mapping with manned aircraft. This data can be fed into models to figure out where water is likely to flow. This informs what sort of flood mitigation measures, like levies, can be built to reduce flood impact.

Floods, Vaal river South Africa, Feb 2023

South Africa- Parys – Valley river floods – 18 February 2023. Following heavy downfalls over the past few days water levels have risen thus affecting the rivers and dams . The river system around the Vaal River and Vaal Dam has seen substantial increase with some areas reporting the worst since 1974. Many properties and vehicles have sustained water damage but no reports of human lives lost has been reported even though several people had to be rescued from their roofs by chopper,  The Star, Timothy Bernard.

This is according to Storm Zurcher, the community policing forum chairperson of the Loch Vaal neighborhood watch area, who was referring to the widespread destruction of homes, roads and bridges in Loch Vaal, Vanderbijlpark and other parts of the Vaal after devastating flooding at the weekend. On Saturday, the department of water and sanitation announced that a further two floodgates had been opened at the Vaal Dam to ease pressure after heavy rains, which unleashed flooding in the region. The total number of floodgates that have been opened stands at 12.

Heavy rain showers means that the Vaal and Orange river system experience rising water levels, the department said, noting how it is continuing to “assess and implement measures to mitigate the effects of the increase”. The continuing heavy rains in large parts of South Africa meant that many rivers “are overflowing and most dams are full and spilling”, the department said, urging all residents in settlements along lower areas of the Vaal Dam to move to higher-lying areas, Mail & Guardian Sheree Bega, 21 Feb 2023.

Drone Technology

Drones have been identified as one of the trending technologies being utilized for flood monitoring and detection due to their capacity to provide an on-demand, larger perspective of the flooded region and map the degree of damage. Drones help complement this suite of tools by capturing footage of flooding as it is occurring.

 

Why is high quality footage of flooding so important?

There are three main reasons why it’s helpful to get as much high-quality footage during flood events as possible:

  1. It helps emergency responders identify areas of high risk. This helps focus evacuation efforts and can help rescuers find and evacuate people who have become stranded in flood water.
  2. It helps disaster response teams prepare and get plans in place for when flood waters recede. Identifying worst hit areas as soon as possible means that resources can be prepared for urgent repairs and restoration of access routes. This helps communities get back on their feet faster.
  3. Aerial flood footage also helps give quantitative records of flood extents and depths. This is important for two reasons:
  • It helps researchers understand flood risk and flood behavioral to help prepare for future flood events
  • It provides direct evidence that can be used in insurance claims and applications for disaster relief funding

Why are drones a good way to capture footage?

While you’re unlikely to see anything in drone images that you wouldn’t be able to see from traditional aircraft and helicopters, drones are often much cheaper and easier to operate. Unlike traditional aircraft, drone flights can be conducted by trained volunteers rather than requiring licensed pilots.

Drones can also be deployed flexibly and on short notice, like during a short break in dangerous weather that would otherwise ground aircraft. Using drones to take footage of flood events also means that manned aircraft can focus on finding and evacuating people that have been stranded by flooding without having to worry about collecting footage at the same time.

Satellite can also be used to assess the scale and extent of natural disasters. But during flood events, cloud cover often presents satellites from capturing any useful images.