Roadway Standards Section 170 - Design Modifications & ADA Exceptions

170.1 Design Modifications

1. It is not the objective of these Standards to limit the creative efforts of engineers in providing alternate solutions to specific problem areas or to relieve the responsibility for professional engineering judgment. 
2. Practical design modifications that preserve the function and safety of the roadway system and offer benefits to aesthetics, resource protection, ease of maintenance, and livability are encouraged.
3. Approval of non-compliant or alternate specifications and standards under the purview of these Standards may be requested utilizing the following process.  This process does not apply to land use requirements or Conditions of Approval generated through the ZDO or the Comprehensive Plan.  The ADA exception process follows the procedures detailed below in Section 170.2. 

170.1.1 Modification Request Submittal

1. Requests to modify design standards shall utilize the Clackamas County Design Modification Request form.  Design Modifications are typically submitted prior to land use application approval or early on in the design process when related to capital construction.
2. Land use conditions of approval are commonly written so that there is little, if any, flexibility after land use approval.  For this reason, it is imperative that design modification requests be addressed prior to land use approval.  If a design modification is requested after the land use conditions of approval are issued, additional application for a modification of the conditions of approval or a new land use application through the Planning and Zoning Division may be required.

170.1.2 Criteria for Modification of Standards

The County may grant a modification when the use thereof does not compromise public safety or the intent of the County's standards and any one of the following conditions are met:

1. The subject standard is deemed not applicable in the particular circumstance.
2. Topography, right-of-way or other geographic conditions impose an environmental concern or provides a constraint for constructability and an equivalent alternative, which can accomplish the same design intent, is available.
3. A minor change to the standard and the modification is required to address a specific design or construction constraint which, if not enacted, will result in an undue hardship.
4. The proposed modification does not compromise safety, function, appearance and maintainability based upon sound engineering and technical judgment.
5. The modification is not in conflict with land use requirements.

170.1.3 Review

1. Type I modifications shall include, but not be limited to, geometric design and the modification or omission of standard roadway cross section elements.  A Type 1 modification requires a higher level of scrutiny than a Type II modification.
2. Type II modifications shall include, but not be limited to, sight distance, access spacing, number of accesses, intersection angle, etc. 
3. The request to modify design standards shall be reviewed first by Engineering technical staff who shall make one of the following decisions:
4. Approve as proposed,
5. Approve with changes, or
6. Deny with an explanation.
7. Design Modification approval shall not constitute a precedent for use at other locations.

170.1.4 Appeal

Applicants may appeal the Engineering technical staff's decision to the Transportation Engineering Manager.  The Transportation Engineering Manager's decision may be appealed to the Road Official, whose decision shall be final.

170.2 ADA Exceptions

The County has adopted the PROWAG standards for ADA accessibility within the public rights-of-way and easements under the jurisdiction of Clackamas County. PROWAG provides justifications for exceptions to the standards for new construction and for alterations to existing ADA accessibility features. Exceptions are required for any accessibility feature that cannot meet the requirements due to a physical constraint identified in the following sections.  Crosswalk closures are also reviewed under the ADA exceptions process.

170.2.1 Exceptions for New ADA Accessibility Features

Exceptions to full compliance with PROWAG standards can only be granted for a limited number of physical constraints preventing full compliance. If an exception is required for a particular feature, efforts must be made to ensure that other elements are accessible. Exceptions for non-compliance with the PROWAG standards for new ADA accessibility features can only be approved when full compliance cannot be achieved due to terrain or historic features. Where the State Historic Preservation Officer or Advisory Council on Historic Preservation determines that compliance with a requirement would threaten or destroy historically significant features of a qualified historic facility, compliance shall be required to the extent that it does not threaten or destroy historically significant features of the facility (PROWAG R202.3.4).

170.2.2 Exceptions for Alterations to Existing ADA Accessibility Features

Where existing physical constraints make it impracticable for altered facilities to fully comply with the ADA requirements, compliance is required within the scope of the project. Existing physical constraints include, but are not limited to, underlying terrain, right-of-way availability, underground structures, adjacent developed facilities, drainage, or the presence of a notable natural or historic feature (PROWAG R202.3.1). 

170.2.3 ADA Exception Request Submittal

1. Exception requests shall be submitted on the ADA Exception Request form.  Exception requests should only be submitted at the following points in the process:
2. Requests for exceptions to waive the requirement for a new ADA accessibility feature as part of a development should be submitted and acted upon prior to land use approval since land use conditions are typically written with little or no flexibility.
3. Requests for exceptions to requirements for a particular element should be submitted during plan review and must be acted upon prior to permit issuance.
4. Requests for exceptions to requirements may be submitted during construction if physical constraints are identified that were not included in the design. In such situations, the project Engineer shall prepare a revised design that maintains accessibility to the greatest extent practicable, and that exception must be acted upon prior to construction of the accessibility feature.
5. Exceptions should not be provided for noncompliant features after construction.
6. Exception requests that are submitted shall be reviewed by Engineering.  The Transportation Engineering Manager will make the decision to approve or deny the requested exception. The Transportation Engineering Manager's decision may be appealed to the Road Official, whose decision shall be final.