Declining water levels on some of Germany's major rivers, including the Rhine, exacerbated by heat and drought, are raising fears that severely constrained riverboat cargo traffic may deal yet another blow to the struggling economy.

The Rhine riverbed is partially dry near steelmaker Thyssenkrupp's blast furnaces in Duisburg, a picture of how low water levels pose a new challenge for German industry.

The mighty waterway also winds past car factories, chemical plants and big river ports as it passes through the industrial heartland of Europe's biggest economy.

Shallow water is imposing tighter limits on how much ship cargo can float down the river – sending prices up for riverboat freight and heaping pressure on the government to act.

On Thursday, newly appointed Transport Minister Steffen Bilger plans to meet in Bonn with industrial executives, shipping companies and port bosses in hopes of finding practical solutions to the unfolding crisis.