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Last week, Oregon City adopted a revised geologic hazard code clarifying the role landslide deposits play in residential density calculations. The amendments were made to align city code with its geologic hazard overlay, which prescribes a two-dwelling unit per acre density calculation in the overlay area only. The city commission was considering a reduction in steep slope threshold within the geologic hazard overlay, and instead decided to implement the code as recommended in HBA’s letter and city staff report, which were based on current geotechnical and geology expertise. By preserving the steep slope threshold in accordance with current geotechnical advice, the city is on the forefront of landslide protection while still being able to accommodate the number of homes projected within its adopted concept plan areas. You can learn more about Oregon City’s geologic hazard code here. Oregon City’s proposal to codify development review criteria for properties with landslide deposits triggered a previous Measure 56 notice to affected property owners last year. Oregon law requires cities and counties to provide this notice to affected property owners when the jurisdiction makes a change in the zoning of their property. This includes any ordinance that changes underlying zones, zoning maps, or limits or prohibits previously allowed uses. Because a steep slope threshold reduction would limit allowed density on certain properties in Oregon City, any proposed changes pertaining to slope, zoning, and property use would require a separate Measure 56 notice. During HBA’s annual BuildRight Conference in April, HBA presented ‘Landslides: Best Practices for Land Use and Construction,’ which included a review of Oregon’s 2019 Landslide Guide for Oregon communities, along with the Oregon City and other case studies from around the region. According to the presentations, the presence of historic landslide deposits are the primary factor in current landslide risk. To request a copy of the BuildRight presentation, or to learn more about HBA involvement in Oregon City, contact Roseann Johnson at roseannj@hbapdx.org.