However, Oregon City does provide some mapping tools you may find useful in helping you map your property: OC Web Maps.
Oregon City's in-house GIS mapping tool, OCWebMaps, contains maps of the approximate locations of your property lines. It's helpful to show the ways in which certain overlays - like Natural Resources, Geologic Hazards, and Floodplains - interact with your property. However, while helpful in planning any projects you might have, OCWebMaps is not an accurate substitute for a professional survey by a licensed surveyor.
Oregon City's in-house Plat Finders can help establish certain dimensions that may prove helpful in determining property lines. However, they are not substitutes for a professional survey.