Growing up in northern Illinois, I remember taking class fieldtrips to historic farms, many of which lined the outer suburbs of Chicago. While each farm had its own unique charms, there was one thing that they all seemed to have in common: watermills. Watermills and other hydropower systems aren’t a new phenomenon, nor are they exclusive to northern Illinois. They have deep roots in ancient cultures, usually serving as an agricultural tool for watering crops or grinding grain. So if hydropower was being used, even thousands of years ago to power agricultural activities, then how is it being used today? How is the US utilizing hydropower?

According to, it is estimated that only 7% of US power comes from hydropower sources. These days, hydropower energy is not coming from watermills; instead, it is coming from dams, usually built across large rivers. Many sources state that the first hydropower plant was constructed in Appleton, Wisconsin in 1882; some other sources state that the first plant was constructed at Niagara Falls. Regardless of the first location of the plant, since the late 1800’s, thousands of dams and power plants have sprung up all across the US. Hydropower is believed to be one of the greatest renewable energy resources, since it only relies on flowing water, something that can be found in every state across the US. Likewise, it produces no emissions and relies on domestic labor. Although other renewables such as solar and geothermal systems decrease in efficiency over time, hydropower plants stay largely unaffected by the wear and tear of time.

According to, there are 80,000 dams across the US, but only 3% have power-producing equipment. Adding power-producing equipment can dramatically increase hydropower production. Washington state relies on hydropower for 70% of its power production, while many states rely on substantially less. According to the US Energy Information Administration, hydropower makes up roughly 48% of all renewable energy produced in the US. Compare that figure to solar power, which makes up 1% of power production in the US, only 1/7th of the electricity produced from hydropower.

In sum, hydropower is still being utilized to provide power to surrounding homes and business. However, there is undoubtedly room for improvement. To encourage the construction and use of hydropower plants, the federal government implemented the Renewable Energy Production Tax Credit as well as the Business Energy Investment Tax Credit (among others). Since hydropower is such a tried and true renewable energy resource, we hope to see more of it in the future.