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ENB-4.25 - Extra Strength Charge Program Administrative Rules


Administrative Rules Adopted by Bureau of Environmental Services Pursuant to Rule-Making Authority



Link to Full Text of Administrative Rules  (PDF Document, 348 kb). What follows is the Table of Contents and an excerpt from the administrative rules:


1.  Applicability

2.  Purpose


3.  Definitions


4.  Regulatory Authority


5.  Billing Methodologies


6.  New and Redevelopment Control Requirements


7.  Inspection


8.  Variance Requests


9.  Enforcement on Fraud and False Statements


10.  Confidential Information 

11.  Administrative Review and Appeals


A.  Explanatory Information


B.  Class Average Table


C.  Sampling Manhole Schematic

These are administrative rules of the Bureau of Environmental Services (BES) for the Extra Strength Charge program. See the Explanatory Information in Appendix A for applicable code citations, policies, and other information relating to these rules.



1.  Applicability

Sanitary sewer ratepayers or their tenants who discharge or have the potential to discharge wastewater with high pollutant concentrations of Biological Oxygen Demand (BOD) or Total Suspended Solids (TSS) must comply with these rules.

2.  Purpose

The purpose of the Extra Strength Charge (ESC) program is to recover the cost of high-strength wastewater treatment from users who discharge into the City’s sanitary sewer systems, which include the separate sanitary and combined sewer. Billing high-strength dischargers on the City water and sewer bill provides rate equity and prevents the costs of treatment for high-strength wastewater from being passed on to the other ratepayers. High-strength wastewater discharges are those with BOD or TSS in excess of those concentrations that occur as part of the City’s base sewer user charge.

3.  Definitions

These rules use the same definitions found in Portland City Code (PCC) Section 17.36, 17.34 and the Fats, Oils and Grease (FOG) program administrative rules (ENB-4.26). The definitions below are unique to these rules:

A.  “Batch Discharge” means a controlled discharge of a discrete, contained volume of stormwater or wastewater.

B.  “Class Average” means the average discharge concentration thresholds of BOD and TSS for a particular business type with and without approved best management practices in place. Class average concentration thresholds are identified in the Class Average Table in Appendix B of these rules.

C.  “Class Average ESC Method” means an ESC billing method based on a ratepayer’s business type and its assumed average discharge concentration per the Class Average Table in Appendix B of these rules.

D.  “Composite Sample” means a combined series of individual and discrete samples taken at selected intervals based on either an increment of flow or time. The samples are mixed together to approximate the average composition of the discharge to the public sewer system, A composite for one day must consist of a pool of samples collected over the period of expected discharge during the production day.

E.  “Food Grinder” means any mechanical device designed to grind or pulverize solid materials for the purpose of making the material suitable for disposal to the sanitary sewer system.

F.  “High-Strength Wastewater” means wastewater which has a BOD concentration in excess of 300 mg/L or a TSS concentration in excess of 350 mg/L.

G.  “Measured ESC Method” means an ESC billing method based on rolling average sampling and analysis of individual businesses wastewater discharge volume and pollutant loading to the City’s sanitary sewer system.

H.  “Non-routine Discharge” means a discharge that is an explainable, uncontrolled release or spill to the City sewer system that is not representative of the normal or expected characteristics of a facility’s wastewater discharge and may include discharges defined as slugloads.

I.  “Sampling Manhole” means a monitoring access point, such as a manhole in sewer lateral that is acceptable to BES and that allows for observation, sampling or measurement of all discharges to the City’s sewer and drainage system.

4.  Regulatory Authority

The City of Portland, as an operator of a publicly-owned treatment works (POTW), must use a rate structure that fairly distributes the cost of its operation to ratepayers, including contributors of high-strength wastewater [Part 35 of 40 Code of Federal Regulations (CFR) Appendix B to Subpart E]. The City has established PCC Chapters 17.34 and 17.36 to regulate, and charge for, high-strength wastewater discharges to the City’s combined or separate sanitary sewer system.

Link to Full Text of Administrative Rules  (PDF Document, 348 kb) 



Adopted by Director of Bureau of Environmental Services December 27, 2011.

Filed for inclusion in PPD December 27, 2011.

Amended by Director of Bureau of Environmental Services February 26, 2013.

Amended by Director of Bureau of Environmental Services January 24, 2014.

Amended by Director of Bureau of Environmental Services January 8, 2015.