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WES Erosion Control

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All development related activity within WES service districts which disturbs 800-sqft or more is required to obtain a WES issued Erosion Control Permit.  Also all development activity within unincorporated Clackamas County which disturbs greater then 1-acre is required to obtain an Erosion Control 1200-CN or 1200-C permit.

Erosion Prevention and Design Manual - The purpose of the Erosion Prevention and Sediment Control Planning and Design Manual is to provide a comprehensive and detailed approach towards controlling erosion on construction sites. It has been updated to include the latest information regarding materials and installation practices. There are numerous other resources available and readers are encouraged to refer to the reference document listed in Appendix D.  This revised version of the manual was created in partnership with the cities of Gladstone, Happy Valley, Lake Oswego, Milwaukie, Oregon City, West Linn, Wilsonville and Oak Lodge Sanitary District and Clean Water Services.

Types of Erosion Control Permits:

Erosion Control Permit – An Erosion Control Permit is required if the development activity disturbs between 800-sqft and 1-acre.  In order to obtain an Erosion Control Permit please complete the Erosion Control Application and plans as specified in the application.  Typically this permit is issued for residential construction and small commercial and industrial addition and improvements. 

Erosion Control 1200-CN Permit –. The Department of Environmental Quality (DEQ) 1200-CN Erosion Control Permit is required for construction activities on sites between one acre and five acres of disturbance to control stormwater runoff. The District is authorized by DEQ to issue and inspect the 1200-CN permits.  To obtain a 1200-CN permit the applicants must submit the required 1200-CN template style erosion control plans to the District for review and approval.  You can download the DEQ 1200-CN Application and  DEQ 1200-CN Templates from our website or you can visit DEQ's 1200-CN Construction Stormwater General Permit page.  Typically the 1200-CN permit is issued for small subdivisions, partitions, multi-family, commercial and industrial projects.

Erosion Control 1200-C Permit – The Department of Environmental Quality (DEQ) 1200-C Erosion Control Permit is required for construction activities on sites five acres and larger to control stormwater runoff. The District is authorized by DEQ to oversee and conduct inspections related to the 1200-C permits; however DEQ issues the actual 1200-C permit at the conclusion of the required 14-day public comment period.  To obtain a 1200-C permit the applicants must submit the required 1200-CN template style erosion control plans to the District for review, approval and submittal to DEQ for the 14-day comment period.  You can download the DEQ 1200-C Templates from our website or you can visit DEQ's 1200-C Construction Stormwater General Permit page. Please refer to the 1200-C Plan Checklist for submittal requirements. For 1200-C Permit Requirements and Application Forms visit DEQ's 1200-C Application page.  An Erosion Control 1200-CN Permit if the development activity disturbs 5-acres or greater.  Typically the 1200-C permit is issued for subdivisions, multi-family, commercial and industrial projects.

NOTE: Before applying for a 1200-CN or 1200-C Permit, you must have Land Use Approval and any required Corps of Engineers or Department of State Lands permits. You will also need a preliminary review of site development plans to ensure that revisions will not affect grading, pipe alignments, water quality/quantity facilities or vegetated corridors.

Erosion Control Inspection – An Erosion Control inspection is required as part of the construction of a single family home, and shall be completed and approved prior to the contractor pouring the foundation or footings.  All non-single family projects such as a commercial, industrial or multi-family shall have the inspection completed and approved prior to any soil disturbance except for the installation of erosion control devices.

Single Family Residences:  To schedule a single family erosion control inspection use your building permit number and call Clackamas County automated inspection request line at 503-742-4720.

Commercial & Other:  To schedule a erosion control inspection for commercial, multi-family or industruial project call our main office number at 503-742-4567 and request to talk with a Development representative.

Erosion Control and plant resouces vendors list: Erosion Control Vendors & Plant Resources (PDF, 31KB)