Jan 22, 2024 United Kingdom

Scottish Water is preparing for the future with surface-based solutions

  • Use cases

We met with David Winter from Scottish Water to chat about their vision and strategy for surface water management. David is the Team Leader for Asset Strategy at Scottish Water, the national water utility that services 2.46 million households.

“Things are changing”, says David. “We see changes in rainfall, permeability, and flooding, and we need new ways of doing things”.

At Scottish Water, they have built a large flood management team that also includes a group that work with implementing long-term planning. The goal is to create guidelines and processes that help transition from traditional grey solutions driven by historic incidents, to bringing blue-green measures on the table as part of the long-term solutions.

“We had to ask ourselves, do we have the tools, data and knowledge that we need to change the way we model and plan surface water”, David continues.

“Our sewers don’t operate as their own systems. That’s why we are developing a more catchment-based approach, instead of looking at only existing issues on property level.”

Figure 1. Example of a flooding at a property in Scotland.

Currently, resolving customer flooding is undertaken using a well-established method of investigation, optioneering, design and delivery on the ground of traditional buried sewerage infrastructure. Using that technique has achieved a lot of improvement, but there is now a need to look beyond the localised solution into the wider catchment and to incorporate rainfall management on the surface as part of the solutions. And this David wants to change.

“Our sewers don’t operate as their own systems” says David. “That’s why we are developing a more catchment-based approach, instead of looking at only existing issues on property level”, explains David.

To assess surface water on catchment scale, there is a need to model and understand surface flow and become better at finding surface interventions that can help reduce and even prevent water from entering the sewer system.

Figure 2. Example from SCALGO Live. Analysis for flooding, catchment extent and flow paths.

“With SCALGO Live, it becomes less about processing data and more about the information.”

As part of the long-term planning, David’s team set up a set of GIS-based tools for analysing catchments and flow patterns. But it soon became clear that the amount of data and the processing of that data was time consuming and difficult.

“When I first saw SCALGO Live I thought that, oh, it does the same as our GIS-based tool but in the fraction of the time”, David declares, “and then it has all the added features such as changing the terrain to make better input data to the hydrodynamic models, and we can start testing various solutions and see what happens”.

“It becomes less about processing data and more about the information”, David concludes.

Figure 3. Workspace solution testing: introduction of storage and surface interception to create managed flow paths and resulting flood risk reduction

Scottish water first started using SCALGO Live in a free trial period to see if the tool could be useful.

“When we started testing SCALGO Live, we made a detailed evaluation of whether the platform could improve our work enough to justify the purchase”, David recalls. “We concluded, for example, that we could dramatically reduce the time and effort required to get an understanding of the catchment extent and its flow characteristics. It is also very useful to set out the correct project scopes, and, on the optioneering side we could quickly assess future flood risk by introducing surface interventions using terrain editing”.

“Blue-green infrastructure should have the same weight in creating solutions as grey infrastructure."

To David, SCALGO Live can play a fundamental role in supporting surface water planning at Scottish Water. He is currently writing guidelines to incorporate SCALGO Live into the everyday workflow.

“We can use SCALGO Live to set the context and for understanding the overall hydrology at all scales within a catchment”, David explains. “We can also use it to create plans and design solutions and it can be a strong platform for communicating our plans”.

When asked what he would like to change in the way they work with flood mitigation right now, the answer is clear.

“Blue-green infrastructure should have the same weight in creating solutions as grey infrastructure. It is the same investment, but it gives so much more benefit for the same amount of money spent”.

Peder Klith Bøcher,
Head of Market, UK