A tree planting project along Northwest Rock Creek Road will take place this October after a culvert was replaced.

COURTESY PHOTO: MULTNOMAH COUNTY - A section of Northwest Rock Creek Road north of Hillsboro where a culvert was replaced earlier this year, prompting a tree planting project along nearby slopes and road closures.A tree planting project will bring road closures to Northwest Rock Creek Road near Northwest Skyline Boulevard north of Hillsboro this month.

The project comes after a culvert was replaced under Rock Creek Road earlier this year, prompting nearby slopes to be rebuilt.

The planting work will take place on weekdays (Mondays to Thursdays) from 7:30 a.m. to 4 p.m. starting Tuesday, Oct. 6.

The work will require some closures of the road to stage plants, equipment and stockpile materials to be used for the day, because Rock Creek Road is only one lane wide above the culvert, said Multnomah County, which maintains the section of road, in a statement.

The road will remain open when crews are not working on-site.

The work is expected to be completed by Thursday, Oct. 29.

When the road is closed above the culvert, orange road closure signs will be placed at the nearest intersections, Multnomah County said.

The detour route when the road is closed is Northwest Skyline Boulevard to Elliot Road to Rock Creek Road.

The culvert replacement project concluded in March. The culvert was replaced because the bottom rusted out, allowing it to clog with dirt and rocks, a county spokesperson said. It failed after the clogged culvert created a lake upstream in Rock Creek, endangering the road and nearby property.

The new culvert is two feet wider than the old culvert, and it's made of a non-rusting material, Multnomah County said.

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