Low river levels across Germany, including on the Rhine, are threatening the supply of shipped materials such as coal, chemicals and gravel, reports n-tv.

The drought comes at a time when demand is particularly high due to an increase in coal use following the gas crisis, causing prices to rise due to supply being unable to keep up.

“We are only allowed to transport about 50 percent of the volume we could,” Roberto Spranzi, chairman of the German Transport Cooperative Inland Navigation in Duisburg, told the news company. Corporate customers will be faced with higher prices and fewer products, he explained.

Due to a lack of forecasted rain that could alleviate the problem, the situation is expected to be causing tensions. “It may happen that not every customer can be served to the extent they would like,” said Jens Schwanen, managing director of the Federal Association of German Inland Navigation (BDB).

Demand for coal in Germany has increased sharply in recent months as a result of the energy crisis exacerbated by Russia’s attack on Ukraine. Alternative sources of gas outside of Russia are currently being looked into, with agreements already being made with Egypt and other African countries.

While uncertainties regarding supplies of gas may push Germany to rely more on dirty fuels such as coal in the short-term, there is hope that the country’s quest for greater energy independence could speed up the energy transition in the medium term.