Wastewater Treatment Plant and Grease Violation

The sewage flowing into the City’s wastewater treatment plant currently has high levels of fats, oils and grease which is causing problems with treating the wastewater prior to discharge to the Columbia River. 

These problems may lead to violations of water quality standards and pollution of the river resulting in closures of local beaches.  The City could be fined by the State for violations. 

The primary source is largely generated by food service facilities (schools, community meal centers, food carts, markets, restaurants).

However, residential units also contribute to the problem, hence this notification.

Common Sources of Fat, Oils, and Grease (FOG):

  • Fried foods
  • Baked goods
  • Cooked meats
  • Butter and other dairy products
  • Gravy and sauces
  • Mayonnaise and salad dressings
  • Food scraps

What is the big deal?

If fats, oils, and grease drain into the sewer system, they can cause treatment failures, slow draining pipes, clogged pipes, and even sewer backups causing costly private property damage.

Failure to maintain a grease interceptor/trap can lead to fines from the city. Save your money and follow some simple practices that can save your home or your business time and money while protecting Mosier’s sewer system.

Food Service Establishment (FSE)

Oregon Plumbing Specialty Code (OPSC) defines an FSE as a facility that engages in activities of preparing or serving food or beverage for consumption either on or off the premises including, but not limited to, restaurants, cafes, food carts, commercial kitchens, caterers, hotels/motels, prisons, correctional facilities, nursing homes, care institutions.

These establishments are responsible for the installation and maintenance of grease interceptors/traps. The city engineer, at his sole discretion, may require any discharger identified by repeated maintenance problems, to provide an appropriate FOG control plan approved and implemented prior to the renewal or issuance of a business license.  The City will issue fines to repeat offenders.

Best Management Practices for All Mosier Residents 

Best management practices are activities that manage and control the disposal of FOG. There are some simple steps you can take to reduce your addition of FOG to the sewer system. 

  • Regularly maintain your grease interceptor/trap
  • Collect used cooking oil
  • Scrape plates and bowls into the trash or compost
  • Wipe pots and pans with a paper towel before washing
  • Have sink strainers or covers on all drains
  • Do not sweep spills into the drains
  • Do not dump anything into the storm drains
  • Use water temperatures less than 140° F

Questions or comments please call or email jayme.bennett@cityofmosier.com, 1-(541)-490-7411.
Commercial inspections will continue to be performed regularly until the issue is fully resolved.

Resources for Homes and Businesses (https://choosesq.com/)

  • 11.02.200 FOG pretreatment required – When. Property owners who operate restaurants, cafes, lunch counters, cafeterias, bars or clubs; or hotel, hospital, factory or school kitchens; or gas stations or automotive service facilities; or other establishments that serve or prepare food where FOG may be introduced to the sewer system shall have pretreatment facilities to prevent the discharge of fat, oil, or grease waste into the city’s sewer system. The city engineer, at his sole discretion, may require any discharger identified by repeated maintenance problems, to provide an appropriate FOG control plan approved and implemented prior to the renewal or issuance of a business license. A temporary license may be approved for a period of six months to facilitate the establishment of a grease interceptor or FOG control plan. Take-out food establishments or other establishments that prepare food, but do not cook in oil or grease, and who serve food only in disposable containers, may be exempted from this requirement, provided their discharges do not violate any limitation or requirement of this chapter. The FOG removal systems shall meet city requirements. Dischargers shall maintain their grease removal system in a manner that will prevent fat, oil, or grease waste from being discharged into the sewer system.
  • 11.02.210 FOG pretreatment facilities – Installation and maintenance. All FOG pretreatment facilities shall be installed, maintained, and operated by the discharger at his own expense. The facilities shall be kept in continuous operation at all times and shall be maintained to provide efficient operation. Dischargers may not add emulsifying agents exclusively for the purposes of emulsifying polar or nonsolid FOG. A service contractor qualified to perform cleaning is required for interceptors. All material removed shall be disposed of in accordance with all applicable city, county, state, and federal regulations.

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PO Box 456
208 Washington St, Mosier, OR 97040
Phone: 877-319-8467 / 541-478-3505
Fax: 877-553-3601 / 541-478-3810 help@cityofmosier.com
Public hours: M-Th, 10 am – 2 pm

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