Erosion control is an important part of any construction project. It is important for maintaining water quality and nutrients in soil. It is also important for protecting nearby streams and the fish and wildlife that inhabit them.
Sediments from disturbed soils can move onto neighboring properties and streets and into sewer systems and other bodies of water. Excessive sediment is a pollutant and damages the functions of both sewer systems and natural watersheds.
Why erosion control is required
The Federal Clean Water Act requires state and local governments to minimize the potential for soil discharges and runoff to pollute nearby waters. Oregon law prohibits the discharge or placement of wastes into waters of the state and the discharge of waste that causes violations of water quality standards.
The Oregon Department of Environmental Quality grants the City of Portland a National Pollution Discharge Elimination System (NPDES) Municipal Separate Storm Sewer System (MS4) permit. The City must comply with all conditions of this permit. The permit requires the City to implement a program to reduce pollutants in stormwater runoff from construction activity.
As part of this responsibility, the City establishes requirements for construction managers to submit erosion prevention and control site plans and to implement and maintain effective erosion and sediment control practices through Portland City Code Title 10: Erosion and Sediment Control Regulations.
What is required for construction activity
Any construction project that includes ground-disturbing activity must meet the requirements of Title 10 and the Erosion and Sediment Control Manual.
Construction activities are subject to the following:
- Visible or measurable sediment or pollutant exiting the site, entering the public right-of-way, or depositing into any water body or storm sewer and drainage system is prohibited.
- Depositing or washing soil into a water body or the storm sewer and drainage system is prohibited.
- Ground-disturbing activities that require plan review and inspection must post erosion control signage per the Erosion and Sediment Control Manual to satisfy public notification requirements.
Those who conduct ground-disturbing activities within the City must comply with the Erosion and Sediment Control Manual, specifically the minimum requirements of Chapter 1.4 and Chapter 3, Erosion and Sediment Control Best Management Practices, which include:
- Installing and making functional best management practices to keep soil on-site and out of water bodies, adjacent property, storm sewer and drainage systems, and/or the public rights-of-ways before the start of ground-disturbing activities.
- Protecting stormwater inlets that are functioning during development by applying and maintaining approved sediment control best management practices.
- Implementing erosion and sediment control best management practices.
- Implementing pollution control best management practices.
- Posting signage on the site of the permitted ground-disturbing activity that identifies the site’s permit number and address and the City’s Erosion Control Complaint Hotline number or the responsible City project manager or inspector. Ground-disturbing activities that do not require a permit (such as landscaping activities or agriculture) are exempt from this requirement. (See Section 2.4 of the Erosion and Sediment Control Manual for detailed signage requirements.)
- Promptly removing any soil, sediment, and pollutants that enter the public right-of-way.
- Applying temporary or permanent soil stabilization to denuded development site areas in conformance with the following requirements:
- Between October 1 and April 30, all denuded sites must be provided with either temporary or permanent soil stabilization as soon as practicable, but in no case more than two days after ground-disturbing activity occurs.
- Between May 1 and September 30, all denuded sites must be provided with either temporary or permanent soil stabilization as soon as practicable, but in no case more than seven days after ground-disturbing activity occurs.
- Sports fields or playgrounds surrounded by vegetative cover or permanently installed curbing are exempt from this requirement.
- Maintaining temporary erosion and sediment control best management practices until permanent stabilization best management practices are established.
- Before a project is completed, covering all exposed soil according to permanent stabilization best management practices, unless the soil is covered by structures or paving.
- Securing or protecting soil stockpiles using temporary or permanent soil stabilization best management practices. Stockpiles of soil may be subject to additional regulations requiring a permit, review, or erosion and sediment control.
Please note: Ground-disturbing activity is prohibited between October 1 and April 30 in the Balch Creek and Forest Park subdistricts of the Northwest Hills plan district.
The Erosion and Sediment Control Manual provides more detailed information about requirements, best management practices, and sample plans for preventing the discharge of dirt, rocks and sediments from a construction site.
Review of erosion control plans
The Bureau of Development Services is responsible for reviewing development activity that occurs outside the public right-of-way for compliance with the requirements described in the Erosion and Sediment Control Manual and Title 10 of Portland City Code. An approved Erosion Sediment Pollutant Control Plan is required for most ground-disturbing activities.
An Erosion Sediment Pollutant Control Plan is a detailed description of where and how activities will be implemented to control erosion, sediment, and pollutants on a development site. The Erosion Sediment Pollutant Control Plan is a central, specific component of the overall site development management plan. The ultimate goal of erosion prevention is to limit the time and area of ground disturbance, keep pollutants separate from stormwater runoff, and stabilize disturbed soil as quickly and thoroughly as possible.
There are two types of approved Erosion Sediment Pollutant Control Plans, depending upon the characteristics of a site: Simple Site Plans and Graphical Plans.
Simple Site Plans
Sites with a lower potential for erosion and sediment discharge are considered simple sites, and applicants may submit a written Erosion, Sediment, and Pollutant Control Plan. The Simple Site Plan may be submitted instead of a graphical plan, provided the site meets allof the following conditions:
- The site is flat (there is less than 10 percent slope in the area of ground disturbance before development).
- There is less than 10,000 sq. ft. of ground disturbance.
- The site is more than 50 feet from a wetland or water body.
- The development project does not involve a land division of 10,000 sq. ft. or more.
- The site is outside of Environmental, River, or Greenway overlay zones.
- The development is not on a site with known contamination.
- The development does not include dewatering with off-site discharge.
See Appendix E of the Erosion and Sediment Control Manual for more information on what is required in a Simple Site Plan. Best management practices identified on the Simple Site Plan require ongoing implementation, inspection, maintenance, review, and updating. Simple sites must identify an Erosion and Sediment Control Manager who will be responsible for complying with the requirements of the Erosion and Sediment Control Manual.
Sites that cannot meet the site characteristic conditions listed for the Simple Site Plan must provide a graphical Erosion Sediment Pollutant Control Plan.The graphical plan must include both visual and narrative elements. The visual elements must be depicted on a construction plan sheet, consistent with the larger land use application or permit submittals for the project. The level of detail for the narrative elements must be consistent with the size and scope of the proposed project. For small non-complex sites, construction notes on the plan sheet are sufficient narrative. Larger or more complex projects may require a more extensive narrative and/or phased plans.
Please see Chapter 2.3 of the Erosion and Sediment Control Manual for more information and requirements for the graphical Erosion Sediment Pollutant Control Plan.
Other types of projects, including those not requiring permits
Projects that do not require a development permit are still required to implement erosion and sediment control practices to meet minimum performance standards. For ground-disturbing activities that do not require a development permit, the private responsible party or lead City bureau is in charge of installing, inspecting, maintaining, and adjusting best management practices during construction to limit erosion, reduce sediment transport, and prevent track-out from the project site. The Bureau of Environmental Services is responsible for enforcement actions related to activities that do not require a development permit.
Erosion control inspections
Erosion and sediment control best management practices must be properly installed, inspected, maintained, and adjusted as necessary to ensure proper performance throughout construction.
Typical inspections during a project include the pre-construction inspection, inspections during construction by both City staff and the on-site erosion and sediment control manager, and a final inspection to verify permanent stabilization is in place. The approved Erosion, Sediment, and Pollutant Control Plan must always be on-site and accessible to the on-site erosion and sediment control manager and City inspectors.
Pre-construction compliance inspection (#200 inspection)
For on-property development permits, an initial erosion and sediment control inspection by the City is required to review the installation of best management practices before any ground-disturbing activity begins. All best management practices must be installed in accordance with the issued permit. This inspection must be approved prior to any ground-disturbing activity.
Please note that if a tree preservation inspection (#507 inspection) is required, it must be approved prior to requesting the #200 inspection.
Ongoing maintenance inspections during construction (#205 inspections)
The City may conduct regular compliance inspections to review erosion and sediment control best management practices and records during construction activity. The City will conduct additional inspections in response to complaints regarding a site or as a result of prior deficiencies. Examples of complaints or deficiencies that might trigger additional inspections include, but are not limited to, sediment going off-site or sediment impacting the effectiveness of the best management practices.
City inspectors have the authority to require immediate maintenance, removal, or adjustment of best management practices to address identified deficiencies. Failure to control sediment or pollutants can result in enforcement actions by the City.
In addition, the on-site erosion and sediment control manager must conduct or oversee regular inspections of erosion and sediment control best management practices throughout the construction process.
Final inspection (#210 inspection)
For on-property development permits, the erosion and sediment control manager is responsible for the removal and proper disposal of all temporary controls at the completion of construction. The City will conduct a final erosion and sediment control inspection, which must be approved before a final permit inspection. Final stabilization best management practices must be in place and functioning before a final inspection can be approved.
Request an erosion control inspection
To schedule an inspection, call the 24-hour Request for Inspection and Inspection Results phone number before 6 a.m. on the day you need the inspection. Be sure to have your permit number or Interactive Voice Response (IVR) number available when you call. Inspection requests called in after 6 a.m. will be put on the list for the next business day.
If you have problems using the IVR system to schedule your inspection, or you receive an error message, please call 503-823-7300.
Learn more about how to schedule an inspection with the City of Portland.
Check the status of an erosion control inspection
Check the status of your inspection online using Portland Maps. Be sure to have your permit number or IVR number available to use the search.
Inspections by erosion and sediment control manager
The on-site erosion and sediment control manager must conduct and document regular inspections, at a minimum:
- Weekly from October 1 through April 30.
- Monthly from May 1 through September 30.
- Within 24 hours of rain events exceeding one-half inch of rain measured within a 24-hour period. The depth of rain will be determined from the nearest active rain gauge reported on the City of Portland HYDRA Rainfall Network.
The erosion and sediment control manager must prepare inspection logs or reports after each inspection. The log or report must document the effectiveness of each best management practice at every location on the site, any needed repair or replacement of best management practices, and any additional or different best management practices that were installed. The log must also document actions taken to clean up sediment. Photographs and videos may be used to document site inspections. Reports must be retained and provided to City inspectors upon request. Sample inspection logs and reports can be found below and in Appendix D of the Erosion and Sediment Control Manual.
Enforcement of erosion control requirements
Erosion control is preventative in nature and compliance is continuous and ongoing once ground-disturbing activity has begun and until the project receives final inspection approval. In order to comply with City’s NPDES MS4 Permit, on-property construction activity regulated by the Bureau of Development Services is subject to the Erosion and Sediment Control Enforcement Administrative Rule. The purpose of the enforcement rule is to establish an escalated enforcement process for violations of Portland City Code Title 10 and the Erosion and Sediment Control Manual. Enforcement processes include initial compliance periods, escalated fees and fines, stop work orders, citations and civil penalties, and compliance agreements.
Enforcement policies and procedures related to ground-disturbing activities that do not require a development permit from the Bureau of Development Services are subject to requirements in the following policies and procedures:
- ENB-4.03 Sanitary Discharge and Pretreatment Program
- ENB-4.13 Administrative Rules for Discharges to the City Storm Sewer and Drainage System
- ENB-4.15 Bureau of Environmental Services Enforcement Program
- ENB-4.30 Bureau of Environmental Services Title 10 Discharge Enforcement
Site development permits
You may need a site development permit for your project. Read more about site development permit applications and apply online.
Unincorporated Multnomah County and erosion control
Multnomah County has information on grading, erosion control and floodplains.