2024 Draft Updates - For Public Comment

Design and Construction Standards DRAFT

Detail Drawings DRAFT

Summary of Chapter Changes

Wastewater: Changes are in “track changes” in red color text. Proposed text is in bold and underlined.  Deleted text is in strikethrough. Proposed changes are minimal and considered “housekeeping”.  No significant changes are proposed. Organizationally, the construction-related chapter has been combined with the design chapter at the request of staff and some designers (customers). Detail drawings have been updated with new adoption dates.

Stormwater: The proposed standards are borrowed from Water Environment Services (WES) and have been slightly modified to reflect Oak Lodge’s MS4 Permit regarding the impervious surface threshold triggering a permit (1,000sf versus 5,000sf).  As compared to the current code, the proposal requires using Low Impact Development / Green Infrastructure (such as open swales) to treat stormwater, offers a sizing calculation that better protects the District’s waterways, simplifies the design calculations for design engineers and the review process for staff.

Water: Changes are in “track changes” in red color text. Proposed text is in bold and underlined.  Deleted text is in strikethrough. Proposed changes are minimal and considered “housekeeping”.  No significant changes are proposed. Organizationally, the construction-related chapter has been combined with the design chapter at the request of staff and some designers (customers). Detail drawings have been updated with new adoption dates.

Proposed Amendment Description: Storm Code Standards

The WES code was adopted in June 2023. Oak Lodge has retained the WES section numbering system which differs from the other Oak Lodge design chapters’ system.

Major changes include the removal of the following WES Code Sections:

• Section 4, public stormwater system expansion
• Sections 7.4-7.10 Infrastructure design standards (referred to Clack. Co. DTD).
• Figures 1-4
• Tables 9-14
• Detail Drawings other than infiltration facilities.
• Definitions are from WES unless Oak Lodge had an existing definition, which then replaced the WES definition.
• Table 1 explicitly provides permitting triggers based on square footage of impervious surface. Developments less than 10,000 square feet can use a “simplified method” (meaning not engineered) which uses an open swale treatment system sized to provide treatment, flow control and infiltration which are the three primary treatment tools.  This now captures single family dwellings - both new construction and additions -  which were not captured in the current code.
• Developments greater than 10,000 square feet must be engineered, include a bond, maintenance agreement, stormwater report / calculations and downstream analysis.
• All triggered construction uses the BMP sizing tool or an equivalent.  This simplifies design and reduces the review time and associated cost. 
• A new requirement is for Oak Lodge to review commercial and industrial operations for potential spills into the surfacewater system.  Examples include automotive repair/painting/detailing outside of a structure, liquid storage, fuel dispensing, recycling or solid waste. These are new requirements from the MS4 permit and will add to staff time.

__________________________________________________________________________________________________

Design and Construction Standards 

Provide guidance on both designing and construction of sanitary sewer, surface water, and water facilities. This document is separated into Divisions and Sections. Sections are guidance design-related for design engineers/applicants and staff to apply. Divisions are guidance construction-related for inspectors and contractors to follow. Sanitary sewer and water detail drawings are included. ​

This document is intended to be updated annually. If errors are found, please cite them and submit them to Oak Lodge Water Services Technical Services Department. Please submit any comments or questions to permits@olws.org call (503) 654-7765.

Standard Details

The above link will direct you to the standard details drawings. For the .PDF files, the link will open the document in the browser. If you "right click" and "save link as" then you can download the PDF. For the DWG files, if you click on the link it will download to your computer directly.

Rule & Regulations

These rules and regulations establish the conditions by which the District will conduct its business and operations and how Customers may receive service.