Hydrological Modeling

Why do we need models?

It is well-known that the number and diversity of water-related challenges are large and are expected to increase in the future. Current and future water-related challenges are location and time specific, and can vary from impact of glacier dynamics, economic and population growth, floods or extended and more prolonged droughts, amongst others.

In response to these challenges, hydrological models have been developed to analyze, understand, and explore solutions for sustainable water management, in order to support decision makers and operational water managers.

The application and development of hydrological models are key activities of FutureWater. This allows us to increase our knowledge about hydrological processes, and provide sustainable solutions for integrated water resources management.

In general, we develop and apply hydrological models for two main reasons: process understanding and scenario analysis.

Process understanding

To understand hydrologic processes, a large amount of detailed quantitative measurements are required at different spatial and temporal scales. The strength of hydrological models is that they can provide output at high temporal and spatial resolutions, and for hydrological processes that are difficult to observe on the large scale that they are generally applied on. Hydrological models therefore enable us to gain insight into hydrologic processes using a limited number of measurements.

Scenario analysis

The most important aspect of applying models is in their use in exploring different scenarios, expressing for example possible effects of changes in population and climate on the water cycle. Models are also applied at the operational level to explore interventions to be used by water managers and policy makers. Examples of this are changes in reservoir operation rules, water allocation between sectors, investment in infrastructure such as water treatment or desalination plants, and agricultural and irrigation practices.

Using hydrological models in scenario analyses we attempt to solve the question “What if…?”. Data and statistics are crucial to evaluate the past and present, but models are critical to investigate options for the future.

Models that we use

FutureWater does not focus on the use of a single hydrological model, but has a variety of models and techniques available. The model that is eventually selected depends on the problem to be addressed and/or the question to be answered. The spatial scale is essential in this context as is the amount of physical detail required for the specific project. Usually one model does not suffice and a combination of two or three models is required. An overview of models that are frequently used by FutureWater is listed below: