Plans to shore up vulnerable bridges against a massive Cascadia Subduction Zone earthquake may sound like a fairy tale, but the threat is real, and any work that can be done before the quake hits will be better than coping with the aftermath if the work isn't done.

One project in particular is the Nevada Street bridge, which has been controversial but could play a vital role in the aftermath of a big quake.

When — not if — it happens, the quake is likely to disrupt the lives of everyone in the Pacific Northwest, collapsing bridges and buckling roads, not to mention taking many lives and interrupting supplies of food, water and electricity.

State and city officials are trying to determine where work should be concentrated to preserve essential travel routes in and out of Ashland as well as statewide.

Key routes in Ashland include Main Street-Siskiyou Boulevard-Lithia Way, Ashland Street, Oak Street-Eagle Mill Road and Mountain Avenue-Hersey Street.

Mountain Meadows residents are concerned about being cut off if the Mountain Avenue overpass across Interstate 5 fails. State officials say it likely would fail in a quake, but isn't on the list for a seismic upgrade. That means building the controversial Nevada Street bridge may be the best solution, which won't please opponents.

No matter what projects make the final list, replacing and retrofitting existing bridges and roads will be very expensive and take decades to complete. But not doing the work risks making an already colossal disaster even worse.