Do You Know Where Your Drinking Water Comes From?
Sioux Falls is one of the fastest-growing cities in America today, and with a growing population comes a greater demand for water. We sat down with Chris Myers, Water Superintendent for the City of Sioux Falls, to discuss the city’s current water usage and the future of water in Sioux Falls. Whether you live in Sioux Falls or another community in the Big Sioux River watershed, this case study applies to everyone. Towns across Eastern South Dakota continue to balance population growth with water usage, drought, water quality issues, and the need for infrastructure improvements.
In 2012, Sioux Falls received its first allocation of water from the Lewis and Clark Regional Water System, a system that, when complete, will deliver water from the Missouri: Elk Point Aquifer to 20 members in South Dakota, Minnesota, and Iowa. Prior to 2012, the city relied on three sources of water: the Big Sioux River Aquifer, the Middle Skunk Creek Aquifer, and Big Sioux River surface water. The water from Lewis and Clark has been instrumental in the city’s ability to grow at a rapid pace. “We heavily rely on Lewis and Clark today and know that the investment that we made in them has an amazing impact on sustaining the growth that Sioux Falls is experiencing and will experience into the future,” Myers said.
How much water does Sioux Falls use? In 2022, the city used 8.2 billion gallons of water, with 56% (4.6 billion gallons) coming from Lewis and Clark, 41% (3.4 billion gallons) from the two aquifers, and 3% (0.2 billion gallons) from Big Sioux River surface water. On average, Sioux Falls residents use 22.4 million gallons of water per day. This number increases in summer to around 32.27 million gallons and decreases in winter to 16.3 million gallons. Myers noted that “despite a growing population, our water consumption has not escalated proportionally.” He attributes this to the City’s proactive approach to implementing technological advancements and conservation programs that decrease per capita daily water usage.
At the Water Purification Plant, the City monitors influent raw water and effluent finished water for more than 250 substances to ensure safe drinking water. Nitrates, a contaminant that we test for at Friends of the Big Sioux River, are included in this list of substances. Nitrates are naturally present in the environment. However, they are often found in excess due to runoff from fertilized soil, animal feedlots, and septic systems. Excess nitrates in drinking water can cause Blue Baby Syndrome, cancer, and other unwanted health effects.
Recent data from across the watershed show that nitrate levels continue to rise gradually in the Big Sioux River but remain within the safe levels set by the EPA through the Safe Drinking Water Act. Other cities in the Midwest, such as Des Moines, regularly see nitrates above the safe level in their raw source water. As a result, they must run their nitrate removal facility to ensure the finished drinking water remains within safe levels. This facility can cost up to $10,000 a day to run, a cost incurred by the ratepayers. At present, the City of Sioux Falls does not have a nitrate removal facility and does not foresee the need for one in the near future. However, it is up to us as watershed citizens to continue reducing our fertilizer usage, picking up pet waste, and reducing runoff to ensure that nitrate levels do not continue to rise.
You may be wondering what the future holds for drinking water in Sioux Falls. According to Myers, the future is bright. The City is in the process of completing a master plan that examines current supply data against the needs of the estimated population growth. “We feel we have enough water today to provide for the next 25-plus years of growth and development,” Myers said. In addition to the master plan, the City has begun work on a new horizontal collector well that will replace a current well built in 1952. This well, located by I-90 and Ditch Road, is expected to be completed by the 2025 peak season. The existing well pulls water from the Big Sioux River Aquifer, pulling about 180 gallons per minute or 0.26 million gallons per day. The new well will pull about 2,776 gallons per minute or 4 million gallons per day. Infrastructure updates such as these are all part of the City’s work to ensure that we have enough water to sustain the future growth of our community for the next 25, 50, and even 100 years.
For more information on the Water Purification Plant and the City’s comprehensive water quality monitoring, visit siouxfalls.gov/water.