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Environmental Services

working for clean rivers

Phone: 503-823-7740

Fax: 503-823-6995

MAILING ADDRESS: 1120 SW 5th Ave, Room 1000, Portland, OR 97204

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About Industrial Pretreatment

field investigationEnvironmental Services issues permits to industries based on their wastewater characteristics or amount of discharge. The permits require industries to monitor for pollutants of concern and to comply with reporting schedules, along with general conditions listed in the permit. 

Permitted Industrial User types include: 

  • Significant Industrial Users (SIUs) - regulated based on process flow or treatment plant loading as defined in Code of Federal Regulations Title 40 Part 403
  • Categorical Industrial Users (CIUs) - must comply with federal standards as listed in Code of Federal Regulations Title 40 Part 405-471
  • Non-Significant Industrial Users (Non-SIUs) - regulated by local limits based on discharging pollutants of concern
  • Non-Discharging Categorical Industrial Users (NDCIUs)
  • Batch Discharge Industries - have limited discharge amounts and are allowed to discharge their waste under managed conditions.

For a look at the City of Portland’s legal authority to implement and enforce this program refer to: 

Pretreatment Background

The National Pollutant Discharge Elimination System (NPDES) and the Clean Water Act have regulated water quality since the early 1970s. This federal program identifies and regulates water pollution from point sources (such as the sewage treatment plant and outfall pipes) and non-point sources (stormwater runoff from streets). 

The City of Portland has NPDES permits for its two sewage treatment facilities, the Columbia Boulevard Wastewater Treatment Plant and the Tryon Creek Wastewater Treatment Plant. The permits require the city to manage discharges to the treatment plants. In 1982, Portland began permitting industrial users and requiring them to pretreat wastewater discharged to the sewer system. 

Pretreatment reduces the amount of pollutants and neutralizes wastewater to meet discharge requirements. Types of pretreatment include pH neutralization, solids separation, metals removal and oil/water separation. Many industries have installed pretreatment systems and control mechanisms to reduce pollutants in their discharge to meet the standards.

Pretreatment Program Activities

  • Permits - The city requires businesses to submit a permit application and an environmental survey, along with baseline pollutant monitoring. City permit managers use this information to develop fact sheets identifying regulation issues, discharge limits and monitoring requirements. Pretreatment staff write permits based on regulation of the wastewater characteristics and compliance with discharge standards.
  • Inspections- The pretreatment staff regularly inspects all permitted industries, and sewer system users that may require permit oversight. Permit managers inspect wastewater processes, discharge points, and pretreatment equipment. In conjunction with other environmental programs, the staff performs stormwater and recycling inspections at the permitted industry, and periodically assists the field operations crew with industrial sampling.
  • Permit Reporting and Administration-- Permit managers develop reporting forms and track pollutant monitoring to determine permit compliance. The Pretreatment Section submits an annual report to the Oregon Department of Environmental Quality to show city NPDES compliance with pretreatment regulations.
  • Compliance and Enforcement-- Staff manages industrial compliance with wastewater permits and issues enforcement actions to bring industries back into compliance. The city is required to produce an annual list of industries that are in Significant Non-Compliance (SNC) with discharge standards or with the permit schedules.

Permit Fees and Extra Strength Surcharges

The City of Portland has implemented cost recovery mechanisms to alleviate the burden on sewer ratepayers of maintaining the sewer system. The city charges industries annual permit fees to pay for a portion of pretreatment program administrative and sampling costs. The city determines fees for each industrial customer using a risk-based tier system. 

The Industrial Extra Strength Sewer Charge (ESSC) Program targets industries that discharge high-strength wastewater to the sewer system. These industrial customers may or may not have discharge limits, but the pretreatment staff monitors them for five-day Biochemical Oxygen Demand (BOD) and for Total Suspended Solids (TSS) concentrations. Discharges exceeding 300 mg/L BOD or 350 mg/L TSS are subject to the ESSC program. The city calculates extra strength services charges using flow rates and monitoring results. 

For more information, contact Industrial Pretreatment at 503 823-5600.