Integrated Water Model

Geonovum Foundation

What happens when there is too much or too little precipitation? What is the quality of my ditch? How much water flows through the sewer? Water calculations answer such questions. An algorithm determines how water moves. The results help make choices for designing and managing outdoor space.

Last change on 28th of May 2025, at 7:53 (CET) | Publication Standard 1.0

• Publication category: Impactful algorithms
• Impact assessment: Field not filled in.
• Status: In development

General information

Theme

• Living
• Nature and Environment
• Space and Infrastructure

Begin date

2025-05

Contact information

[e-mail]

Link to publication website

https://www.digitaleoverheid.nl/innovatieproject/standaard-voor-transparantie-besluitvorming/

Responsible use

Goal and impact

What is hydrodynamic simulation software and why is it important?

Hydrodynamic simulation software helps us accurately understand and predict water flows - such as rivers, stormwater runoff or floods. The software does this by calculating how water behaves in a given area based on physical laws (such as the laws of fluid dynamics and gravity).

These calculations are integral: they take several factors into account simultaneously - such as rainfall, soil type, elevation differences, wind and even the operation of pumping stations and locks. This creates a complete picture of the water system.

The big advantage? We can explore scenarios before they occur in real life. Think of simulating a violent storm to see where water accumulates, or how interventions in the landscape can better control the water.

The impact is huge:

Predictive capability: We can better assess flood or drought risks.

Better decisions: Governments and engineers can make informed choices about water management, infrastructure or spatial planning.

Safety and efficiency: We prevent damage and save costs by knowing in advance what works.

In short: hydrodynamic simulation software translates complex physical processes into clear insights that allow us to better plan, protect and build a water-safe future.

Considerations

This approach is based on physics and mathematics, not artificial intelligence. This means that creating a simulation sometimes takes more work than with a trained AI model. The big advantage is that you don't need large amounts of data to still arrive at an accurate result. Moreover, the results are easier to understand and control. This algorithm is especially suitable for calculating land-based and urban water systems. It is less applicable to oceans, deep groundwater or drinking water pipelines.

We are applying the algorithm as part of a PoC for a study on the standard for transparent decision-making Link to external pagehttps://geonovum.github.io/logboek-dataverwerkingen-voor-objecten/

Human intervention

It is verified with people in the neighbourhood whether the predictions of the water model match reality.

Risk management

The quality of the model's prediction is highly dependent on how well physical reality is modelled as an input to the calculation.

Legal basis

This Algorithm is now being applied in a "proof of concept", but when taken into production at a municipality could be used, for example, for:

* Environment Act: licensing, planning

* AWB (general administrative law act): Monitoring dangerous situations where competent authority takes care of General Principles of Good Governance

- Accuracy

- Transparency

- Proportionate consideration

* Safety Regions Act

Responsibilities of (semi-)public actors in flood relief

When responding to disasters, such as floods, mayors are primarily responsible for safety within their municipal boundaries. Under Section 5 of the Security Regions Act, the mayor has supreme command in the event of a disaster or serious fear thereof; all relevant actors participating in the disaster response are under his command. This means that the mayor is central to the coordination and implementation of measures such as evacuations, communication and maintenance of public order.

At the same time, certain tasks have been transferred to the security regions. These regional cooperative bodies consist of several municipalities and other partners, and were established to make the management of disaster response and crisis management more efficient and effective, especially in disasters that cross municipal borders, such as floods. It is practical and necessary that instead of each mayor acting individually, they work together within a security region to ensure coordinated action.

According to Section 10 of the Security Regions Act, the tasks of these regions include identifying disasters and risks, preparing for disaster and crisis management, and organising the actual response to disasters. This allows security regions to provide regional policy and operational support to municipalities and other involved actors such as provinces, water boards and hospitals.

Links to legal bases

• Omgevingswet: http://wetten.overheid.nl/jci1.3:c:BWBR0037885
• Algemen Wet Bestuursrecht: https://wetten.overheid.nl/BWBR0005537
• Wet veilgheidsregio's: https://wetten.overheid.nl/BWBR0027466/2025-02-12/0

Operations

Data

The model has two types of data as input. First, a model of the physical environment through which water flows, i.e. sewer systems but also surface elevation, e.g. the land use map, or the general elevation file. Supplemented by expert knowledge. Second, Dynamic data on water, for example precipitation data from KNMI or water levels of rivers and or seas from RWS.

Links to data sources

• KNMI neerslag gegevens: https://dataplatform.knmi.nl/group/precipitation
• Riolerings gegevens Rioned: https://apps.gwsw.nl/
• Algemeen Hoogtebestand Nederland: https://www.pdok.nl/introductie/-/article/actueel-hoogtebestand-nederland-ahn
• Landgebruikkaart STOWA: https://stowa.lizard.net/viewer/map

External provider

Nelen & Schuurmans