Impacts of Drought and Extreme Heat on River Water Levels --
An article titled “Drought Makes Upper Rhine Unnavigable, Driving Barge Rates to New Record” was published by The Maritime Executive on 30 July 2026 reveals that, according to a new study by researchers at Imperial College London and ETH Zurich, drought and extreme heat events cause a low water level at Upper Rhine and make that part of the river unnavigable and shipping along the river more costly.
In fact, drought and extreme heat make profound impacts on waterways and water bodies at global scale. As a river advocate at California Institute of Environmental Design & Management (CIEDM), I’m sharing the story of two well-known rivers in the US as following:
1. Mississippi River
The Mississippi River, with its the largest drainage basin in the United States, it collects water from all or parts of 31 states and covers 40% of the continental US. Not only millions of people in more than 50 cities depend on the Mississippi for their drinking water, the river is the US most important commercial waterways, with an extensive transportation network moving goods and foods across the nation. However, it has faced recurring low water level problems driven by persistent upstream drought, and reduced tributary contributions.
As an One Mississippi’s River Citizen and Friends of Mississippi River’s River Guardian, I‘ve monitored and lectured various issues with the river and its basins for several years. The recent extreme heats contributes significantly to its low water levels by increasing evaporation and intensifying drought conditions. These shallow conditions especially at the Lower Mississippi River have narrowed shipping channels, caused barge grounding, complicated commercial barge navigation, and allowed saltwater from the Gulf of Mexico to move upstream, and regularly triggered emergency responses. I’ve joined Mississippi River Network (MRN) to take part in National Mississippi River Day and River Days of Action spearheaded by MRN in June 2026 to celebrate, protect, and connect with our nation’s most iconic waterway.
2. Colorado River
The Colorado River, the longest river in the American West, is facing a severe crisis driven by a long-term megadrought and rising temperatures. This crisis threatens water and power supply for 40 million people and agricultural production in and around the river basin, including Southern California where I live and is connected and supplied by the river water via Colorado River Aqueduct. As a stakeholder, I've also monitored and lectured about the river and its challenges for many years.
As river water level drops low with urged needs for navigating through troubled waters of water shortages, hydropower loss, and groundwater depletion, we stakeholders at CIEDM are rising up to raise public awareness of the needs for conservation and restoration of water resources and ecosystems, by taking actions, for example, to take part in the American Rivers’ Colorado River Day with a cleanup of the Arcadia Ecohome Microforest and adjoining public streets to reduce stormwater pollution at local waterways and an online campaign for water efficiency and resiliency.
