Greener dams

First Humboldt Foundation Postdoc Climate Protection Fellow at TU Darmstadt

2023/11/21 by

The management of dams also has an impact on the environment, and their operators must adapt to climate change. Dr. Mohsen Dehghani Darmian is working on what a more sustainable and gentle water withdrawal strategy could look like in the future.

Dr. Mohsen Dehghani Darmian and Professor Britta Schmalz

The Iranian water engineer Dr. Mohsen Dehghani Darmian is the Alexander von Humboldt Foundation's first postdoctoral climate protection fellow at TU Darmstadt. He has been researching more climate-friendly management strategies in Professor Britta Schmalz's Chair of Engineering Hydrology and Water Management since April, using the Rappbode Dam in Germany's Harz Mountains as an example.

The Rappbode Dam winds its way along nine kilometres of the valleys and mountains in the Harz region. The Brocken National Park is not far away. The reservoir, which is considered the largest drinking water reservoir in Germany, holds around 113 million cubic metres of water. But even something as apparently harmless as a dam can harm the climate – with its emissions. As Dr. Mohsen Dehghani Darmian and Professor Britta Schmalz explain, reservoir water contains phosphorus and nitrogen compounds.

“Emissions develop due to the long-term stratification of the water temperature and increasing concentrations of chemical elements. This is accompanied by the decomposition of dead algae, a lack of oxygen in the water columns, and a deterioration in water quality,” add the researchers. “However, efficient dam management strategies can control and reduce these emissions,” emphasises water engineer Mohsen Dehghani Darmian. “And that's what we're working on.” One option for preserving the ecosystem of water bodies is to control thermal stratification.

Optimum strategy

Water is extracted from dams through outlets at different heights of the dams. Depending on the season, different heights mean different water temperatures as well as different water quality indices, such as the concentration of oxygen and other chemical substances. In his research project, Mohsen Dehghani Darmian intends to analyse the effects of targeted water extraction from different dam outlets on water temperature and water quality indicators. He wants to determine what the optimum strategy must look like so that the dam management can adapt to climate change and mitigate the consequences.

Mohsen Dehghani Darmian is the Alexander von Humboldt Foundation's first International Postdoctoral Climate protection Fellow at TU Darmstadt. He is currently one of only five postdocs at universities that are supported by the Foundation with funds from Germany's International Climate Initiative. The initiative is based at the Federal Ministry for Economic Affairs and Climate Action.

Expanding the network

Dr. Mohsen Dehghani Darmian
Dr. Mohsen Dehghani Darmian

The young scientist, who studied civil engineering with a focus on water at the University of Sistan & Baluchestan in Zahedan, Iran, and also received his doctorate there in 2020, specifically chose TU Darmstadt for his first stay abroad as a researcher. “I want to gain new experiences in Germany. It's a tremendous opportunity for me to expand my scientific career,” says the 32-year-old, who will conduct research at the TU for two years. And Professor Schmalz also appreciates the scientific exchange and the different approaches and perspectives that international researchers like Mohsen Dehghani Darmian bring to her team at the Department of Engineering Hydrology and Water Management. “This will enable us to expand our international network and to establish future collaborations,” she emphasises.

“Solid database”

A new cooperation has already been established and contractually sealed as well – with the operators of the Rappbode reservoir. The climate protection scholarship holder and the TU professor chose the dam for the project “because a solid database is already available here,” says Britta Schmalz. The young Iranian scientist can use this to develop models for climate-friendly strategies for dams. The plan, he states, is to combine the data tools and hydrodynamic models for water quality modelling with artificial intelligence. A new path that may benefit research, water management and – hopefully – the climate.