The long delayed and hugely expensive Highway 99 tunnel underneath the Seattle waterfront won't open until early 2019, according to a news release today from the Washington State Department of Transportation (WSDOT).

WSDOT said in January of this year the tunnel would open in the fall, but now that deadline has been pushed back to early next year. This delay, unlike earlier setbacks, is not Bertha the tunneling machine's fault. WSDOT just doesn't want to upset holiday traffic.

Before the new tunnel can open, crews must first completely close Highway 99 for three weeks as surface streets are realigned and new tunnel entrances are paved. WSDOT calls that closure "the longest major highway closure to ever hit the Puget Sound Region."

The state didn't want bring gridlock to downtown and the surrounding region during the holiday's heavy travel season, so the closure won't begin until Jan. 11, 2019.

That means the tunnel is now a full three years late on its original opening date of December 2015. The tunnel has faced numerous delays after its "Bertha" boring machine overheated, broke its bearings, and caused a sinkhole, which has added up to over $600 million in cost overruns.

Bertha started boring at the south end of the tunnel in July of 2013 and finally broke through the tunnel's North entrance in the shadow of the Space Needle in April of 2017.