Treatment Process

Water is piped from the river presedimentation facilities on the Missouri River and Kansas River and wells along the Kansas River to the Hansen Treatment Plant. It is then treated by a combination of chemical and physical reactions to produce clear, safe and attractive drinking water.

The large amount of suspended matter typically present in the rivers has already been reduced at the presedimentation facilities. With the larger particles removed by presedimentation, the remaining dispersed solids are removed at the Treatment Plant by coagulation, flocculation, sedimentation and filtration.

The first treatment units at the plant are a series of two clarification basins where coagulants and alum are stirred into the water. This causes the dispersed particles to clump together and settle out.

Lime and/or soda ash are mixed with the water in these tanks to soften it. They combine with the hardness of the water to form a precipitate which settles out. The removal of solids in the settling process is one of the most visible in the treatment process. One can see a cloud of solids at the bottom of the basins which is distinct from the clear water above it.

Coming out of the first clarification basins, the pH is high due to the lime softening process. Carbon dioxide, added at this point to lower the pH, makes the water stable and non-corrosive. More coagulants, stabilizers and disinfectants are added in the second clarification basin.

After flowing through dual-media anthracite and sand filters and into the clear-well or reservoir, the water is disinfected with chloramines.

From the reservoir the treated product is pumped into the District’s distribution system to be consumed – clean, safe, potable, drinking water.

Monitoring and Testing

Testing your water for safety and purity has become a highly sophisticated process using a wide array of mechanical, chemical and electronic detectors.

Frequency of Testing

On a daily basis, water samples are taken and tested at various stages of the treatment process. Finished water, as it leaves the plant, is analyzed as well. These water samples are tested for many parameters, including turbidity (clarity), dissolved chemicals, hardness, color, pH, alkalinity, chlorine, ammonia and fluoride. Throughout the distribution system, samples are collected and tested to help ensure potability  and remain safe for consumers.

Samples of river water and finished water are tested at various stages of treatment and analyzed for additional chemical compounds such as sulfates, phosphates, silica and other constituents on a monthly basis. This helps to monitor seasonal or long-term trends in quality.

Samples of each plant's finished water are also analyzed on a routine basis for pesticides and herbicides for which maximum contaminant levels have been established. Samples are collected at the plants and tested for volatile organic compounds, as well as for other organic compounds that currently do not have established standards.

Some critical parameters are checked by continuous, round-the-clock laboratory instrumentation. These instruments monitor the treatment process and provide control information to the plant operators.

Customer-Requested Testing

Water quality data is reported to state and local health authorities. The analyses that are performed in our laboratory or by other agencies are summarized into water quality reports that are made available to our customers.

If you suspect a water quality problem in your home, contact or call WaterOne at 895-1800.