Des Moines Creek Treatment Plant was completed in 1965. At that time is was a Primary Treatment Plant designed for a flow of 1.91 million gallons per day (MGD). Primary treatment consists of removing floatable and settle-able organic material from the waste water and then disinfecting it with chlorine. The settled material is stabilized in an Anaerobic Digester.
In 1982 the plant was expanded to a 6.0 MGD plant by adding additional primary clarifiers, mechanically cleaned bar screens, grit removal, a 500 KW backup diesel generator, and new laboratory facilities.
In 1984 a larger Anaerobic Digester and a chlorine contact chamber were added.
In 1989 the plant was upgraded to Secondary Treatment. The treatment scheme is called Trickling Filter Solids Contact and increased the pollutant removal level from 37% to greater than 85%.
Odor scrubbing for the entire plant was completed in 1991.
In 1999 due to increased wastewater flows the treatment plant was expanded again by adding a second Anaerobic Digester, a 1000 KW backup diesel generator, and Ultra Violet Disinfection. This upgrade discontinued the use of Chlorine. The plant rating was increased to 9.0 MGD at that time.
To read the full history of Midway Sewer District, click here. Full Midway Sewer History
The Des Moines Creek Wastewater Treatment Plant offers tours to individuals, schools, and community groups free of charge. Tours generally take about one hour to complete. It is an opportunity to find out first hand how your sewage is treated, including how the solids are removed and what processes are employed to significantly remove pollutants from your wastewater before it is disposed of. Be sure to schedule your tour group early.
Call 206-824-2760 to make your tour reservation.