Crews will be replacing substandard guardrails along the Blue Ridge Parkway from Milepost 0 in Rockfish Gap to Milepost 356 in Asheville.

Parkway officials said the construction work would take an estimated 600 days.

Crews will be closing one lane of traffic while working and drivers should expect a delay of up to 15 minutes.  Contract work will only be held on weekdays from 8:00 a.m. until 5:00 p.m., with only occasional work on the weekends.

The project is expected to be completed in the spring of 2011.