Aquionics UV solution reduces energy and maintenance costs at City of Silverton wastewater treatment plant
UV disinfection technology treats one million gallons of wastewater per day for reuse in award-winning botanical garden irrigation project
Ultraviolet (UV) disinfection systems from Aquionics are producing significant energy and maintenance savings for a wastewater treatment plant in the City of Silverton, Oregon. The facility collects all the residential, commercial and industrial wastewater produced by the city, and the treated effluent is then reused to irrigate a nearby botanical garden in a project that has won a national award.
The Silverton Wastewater Treatment Plant comprises several traditional wastewater treatment technologies, including secondary treatment by activated sludge, clarification, and disinfection using UV. The city’s National Pollutant Discharge Elimination System permit has stringent standards for effluent treatment and discharge, and it conducts more than 3,100 laboratory tests each year on wastewater throughout the treatment process to ensure that these standards are being met.
Up to one million gallons per day of treated effluent from the plant is reused for landscape irrigation at the nearby Oregon Garden, a beautiful 80-acre botanical garden that is a popular visitor attraction for locals and tourists. The wetlands formed by the treated reclaimed water is a habitat for a variety of wildlife and plants. Any treated effluent not required by Oregon Garden is returned to the local receiving stream, Silver Creek, after meeting all necessary environmental requirements.
Since the plant opened in 1999, Aquionics systems have successfully been providing UV treatment, in line with regulatory requirements. In 2018, the city’s public works department opted to upgrade the UV disinfection technology at the plant, installing two Aquionics InLine 16000+ municipal UV systems. Their greater energy efficiency compared to the previous systems, which had been in place for almost 20 years, will reduce energy costs by almost $9000 per year. In addition, the enhanced chemical cleaning system of the new equipment will cut maintenance time by between 50 and 75 percent, thereby further reducing operational costs.
The InLine 16000+ UV systems each contain 12 medium pressure UV lamps and are designed to produce a three-log reduction of E. coli and achieve the discharge requirement of 126 E. Coli/100 ml. The systems were installed in existing piping with minimal modifications, allowing for an easy upgrade and retrofit. Utilizing electronic lamp drivers, the new UV systems offer a power turn-down from 100 percent to 35 percent, helping to optimize energy consumption.
The systems include the Ultrawipe™ chemical assisted cleaning mechanism, which enhances standard mechanical cleaning by injecting a small amount of fresh acid on each quartz sleeve during the wiping process. This reduces fouling of the quartz sleeves, thereby reducing the need to perform manual cleaning. Aquionics personnel performed on-site support for the upgraded systems, providing certification that the equipment was correctly installed and set-up.
“Meeting strict water treatment standards requires reliable disinfection technology and the Aquionics UV systems have been providing this since the facility opened,” said Brad Jensen, lead operator at the Silverton Wastewater Treatment Plant. “The new energy-efficient Aquionics systems not only provide peace of mind when it comes to meeting regulatory requirements, but also provide significant energy and maintenance savings.”
At the 2018 national WateReuse Symposium held in Austin, Texas, the City of Silverton’s reuse project was named winner of the Community Water Champion Award – part of the event’s Annual Awards for Excellence. The award recognizes utilities or local government organizations that showcase exemplary water reuse projects, systems or facilities that demonstrate the value of water reuse to their communities.
To learn how the latest UV disinfection technology can improve water and wastewater treatment within your operation, visit
the municipal wastewater section of this website.