If you're heading north from SODO, take note that as of today, construction to SR 99 ramps start today.

Since the Alaskan Way Viaduct opened in 1953 drivers have used the ramps at First Avenue S. to get on and off the double deck highway. That will change forever over the course of the next two weekends as WSDOT takes two giant steps toward replacing the viaduct.

A new ways to get on and off SR 99 to be expected in the coming weeks.

Here’s what to expect:

Friday, Feb. 11 to Monday, Feb. 14: First on the docket is the southbound off-ramp. This Friday at 7 p.m. crews will close the ramp and re-route it from First Avenue S. to the intersection of S. Royal Brougham Way and a new street called East Frontage Road S. The re-routed off-ramp and the new East Frontage Road S. will open by 5 a.m., Monday, Feb. 14.

Friday, Feb. 18 to Tuesday, Feb. 22: Even bigger things are happening to the northbound on-ramp. Starting at 7 p.m. on Friday, Feb. 18 crews will close the northbound on-ramp, the southbound off-ramp and all lanes of First Avenue S. between S. King Street and S. Royal Brougham Way. During the extended closure crews will demolish a section of the northbound on-ramp. First Avenue S. and the off-ramp will reopen by 5 a.m. Tuesday, Feb. 22, but the on-ramp will stay closed while crews rebuild the ramp and connect it to the intersection of S. Royal Brougham Way and East Frontage Road S. All of this work will be complete before the Seattle Mariners home opener.

Visit the project website for more information.