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About Vernonia's voice. (Vernonia, OR) 2007-current | View Entire Issue (Jan. 17, 2019)
city january17 2019 9 City Completes Wastewater Treatment Upgrade continued from front page Hyporheic Discharge system are pilot projects that have been used in other utilities around the country but are being implemented for the first time in Oregon as part of Vernonia’s upgraded system. During the recent tour of the facility the system’s operation was ex- plained. Wastewater first enters the treat- ment system through the headworks where any non biodegradable solids are removed. The headworks was installed sometime around 1999. Waste water flows from lagoon #1 to lagoon #2 and is then passed through a chlorination con- tact chamber where it is further cleaned, before flowing to la- goon #3. While in the lagoons the solids set- tle to the bottom and dissolve over time through what is called an anaerobic digest- ing process. “That’s the smell we get in town in the fall be- cause when the weather and water in the lagoons cool down the bacteria flips and then the methane smell is on the top of the lagoon,” explains Mitchell. While in lagoon #3 the chlorine dissipates before the wastewater is sent through a series of 48 Bio-Dome units which remove excess ammonia from the wastewater. In the winter months, be- cause of the large amount of rain runoff and stormwater, as well as the higher volume of water in the river, wastewater effluent can then be discharged directly into the Nehalem River. The Bio-Domes were originally researched by the Public Works Com- mittee and were installed this summer by Wastewater Compliance Systems out of Utah. The domes contain bacteria which is specifically grown to remove unwanted materials. “It’s being used in multiple states to treat a number of different needs,” says Mitchell. “It’s used by dairies, by golf courses in their ponds, and we’re using it to remove am- monia. They did a study on our system and determined how many units we would need. Our contract with them says they’ll add more units if what was origi- nally installed does not accomplish our treatment levels. It also says they will come out in 10 years and replace any VNC 503-429-9333 Recreational & Medical Marijuana Dispensary worn out parts.” In summer months, instead of pumping directly into the river from la- goon #3 the wastewater is pumped back through the Disk Filter and DAF system, two other new elements in the upgraded system. The Disk Filter removes larger particles of sediment. In the DAF, air pressure bubbles are pumped into the wastewater forming a kind of “seafoam” with any remaining sediment, which floats to the top and is skimmed off and Above: Members of the Vernonia City Council, Public Works Committee, and City staff on a recent tour of the wastewater treatment plant and sewer lagoons. Left: The Bio-Domes before installation. removed. The wastewater is then dis- charged through the Hyporheic Dis- charge system - a series of four perfo- rated pipes buried in the ground between the lagoons and the river. The system uses drain fields in the silty/sandy layer of the ground as a natural filtration sys- tem to clean and cool the effluent before it enters into the water table. Three of the pipes and drain fields are currently be- ing used, while a fourth is being held in reserve for future growth. “The reason the Hyporheic Dis- charge system works for us is because of our vicinity to the water table and the river,” explains Mitchell. “Mike Penny from DEQ originally had the idea for us to try this system. The reason for the Disk Filter and DAF is because we want anything released into the drain field to be absolutely free of sediments so it continues to function and lasts as long as possible for the community. We don’t want to send anything through that would clog that drain field.” Monitoring wells between the drain fields and river confirm that the wastewater discharged through the sys- tem is having no negative impact on the water quality in the river. Mitchell says an added advan- Breakfast, Lunch & Dinner 9 Beers on Tap tage of the Disk Filter and DAF system is that if future regulations are more stringent, the City has the ability to fur- ther clean their discharge, by adding a coagulant in winter months, in order to remain in compliance. The financing for the project is somewhat convoluted, and extends over several decades, but is definitely worth examining. The City has taken out sev- eral loans towards upgrading their sys- tem in order to be in compliance with DEQ regulations, including $1.1 million from USDA in 1992 which was sched- uled to be paid off in 2022, and a second loan from USDA in 1995, scheduled to be retired in 2025; both those loans were paid off early in 2017 and 2016. In 2006 the City received a $4.6 million loan from DEQ to design and construct a new wastewater facility. The planning portion of the project was com- pleted prior to the 2007 flood when the lagoon system was completely breached, and it was determined that the design was inadequate, so the City applied for, and was awarded, a Community Devel- opment Block Grant to redesign the sys- tem. In 2013 the City borrowed $5.7 million from USDA for construction, half of which went to pay down the 2006 DEQ loan, and was also awarded a $2.2 million grant from USDA to help with the cost of construction. According to City staff, because of sound fiscal management and the cre- ative use of financing options during construction, the City has excess funds which will be used to pay off the 2006 loan in March of this year – the third sewer loan the City has paid off early in the last three years. With three loans all being paid off early, and the $2.2 million DEQ grant, the City of Vernonia owes just $5.5 million with a payoff date of 2056. Following the upcoming annual Utility Rate Review process which takes place prior to the City starting its annual Budget process in the spring, it is expect that City utility customers will see a rate reduction at the start of the fiscal year in July because of the early loan payoff; City utility customers received a small reduction last year after the retirement of the USDA loan in 2017. These loans and grants the City was awarded helped the City raise the walls of the three dikes and upgrade the three sewer lagoons by two to three feet to protect against flood water inundation during any future flooding events. Funds were also used to install perimeter fenc- ing around the entire wastewater system. The project to raise the dike walls used clay material from the mill site owned by the City directly adja- cent to the wastewater plant, saving the City tens of thousands of dollars in material and hauling fees. The walls of all three dikes were reinforced with rip rap rock during that process of the proj- ect. “Our goal was to leave things better than we found them, and I really think we’ve done that with this project,” said Mitchell. Vernonia’s Voice is published twice each month on the 1st and 3rd Thursday. Look for our next issue on February 7. Home of the Bear Creek Pub Growlers To Go Prime Rib Dinner every Friday & Saturday Check us Out on Facebook Serving the Community Featuring: • Edibles • Concentrates • CBD Oils, Topicals, & Tinctures • Flower Grams & Pre-rolled Joints Owned and Operated by Don & Kim Wallace Vernonia’s Natural Choice Open 7 days 10am - 8pm 886 Bridge Street 503.429.0214 831 Bridge St. DON WALLACE, PLS Professional Land Surveying 1224 E. Alder St. Vernonia, OR 97064 Phone: 503-429-6115 FAX: 1-866-297-1402 Email: DWallace_KLS@msn.com CORPORATE MEMBER
