America’s rivers are beset by unrelenting population growth according to an article published by NumbersUSA.

The plight of rivers was further highlighted last month at World Rivers Day, an annual global event that falls on the fourth Sunday of every September.

Rivers play a vital role in the lives of everyone on the planet, as well as the environment, and World Rivers Day serves as a rally cry to safeguard rivers for future generations while preserving the ancient fabric of life that depends on these aquatic ecosystems. This message has become critically important in America where rivers face an abundance of threats, such as pollution and overuse from human population growth, which impacts on their resilience to droughts and floods.

The most dramatic example is the beleaguered Colorado River, which is suffering from drought and overuse.

The Colorado River, one of the most important river systems in the U.S., is drying up at an alarming rate. It is now considered one of the most endangered rivers in the world by conservation nonprofit American Rivers.

The Colorado River Basin supplies drinking water to 40 million people in the U.S., as well as two states in Mexico, according to the Bureau of Reclamation. It also fuels hydropower resources in eight states and remains a crucial resource for 30 Tribal Nations and agriculture communities across the American West.

According to economists at the University of Arizona, the river system supports $1.4 trillion of the annual U.S. economy and 16 million jobs in California, Arizona, Nevada, Utah, Colorado, New Mexico and Wyoming – equivalent to about 1/12 of the total U.S. domestic product.

Other examples of stressed and misused rivers include the Mississippi River, the Mobile River (Alabama), Tar Creek (Oklahoma), the Los Angeles River, and the Lower Kern River (California), all which suffer from pollution, damming, and/or overuse. Population growth within these respective watersheds is driving the rivers’ worsening problems.

River flows have lowered significantly as expanding populations draw on them for irrigation and drinking water. Water quality has also worsened as a result of sewage and/or urban runoff.

Despite America’s Clean Water Act, many of its rivers are suffering, with no relief in sight, as the country’s population continues to soar to unprecedented levels.

The Census Bureau projects America’s population will grow by another 50 million in the next 35 years.