Roundabout Details
SW Terwilliger Blvd. / SW Palater Rd.
- Type
- Roundabout
- Status
- Existing
- Functional Class
- Other (At-Grade)
- Lane Type
- Single-Lane
- Control Type
- All-Way Yield
- Previous Control Type
- One/Two-Way Stop
- Other Control Type
- None
- Approaches
- 4
- Driveways
- 0
- Diameter (ICD)
- 38.10 m
- City
- Portland
- County
- Multnomah Co.
- State
- OR
- Country
- United States
- Latitude
- 45.45290
- Longitude
- -122.67660
- Year Completed
- 2002
- Notes
- Roundabout replaces existing Y-intersection, adds fourth leg to serve college law school. Includes driveway into roundabout serving two homes. Roundabout is on tilted plane with central island plane steeper than inscribed circle plane to manage cross slopes. Northeast leg (Palater Road) has 8-9 percent grade down into roundabout, then flattens using a short vertical curve to a zero percent crown at the top of the circulatory roadway. Maximum grade through the roundabout is 4 percent; maximum cross slope is -2 percent. First roundabout under City of Portland jurisdiction.