SEATTLE — Washington would need to spend nearly $15 billion over the coming decade just to get its transportation system of roads, bridges and ferries to a “minimally acceptable condition,” according to a state report.

The Seattle Times reported that’s twice the current spending on preservation, which the Washington State Department of Transportation defines as planned repairs that extend the life of an asset, as opposed to stopgap jobs like pothole filling.

“While WSDOT has been deferring this work to try and keep the entire state highway system operational, it can no longer be ignored without dire consequences,” the state report says.

Preservation funds would grow in all four versions of the multiyear transportation packages lawmakers have proposed this legislative session, ranging from $10 billion to $22 billion, using mainly higher fuel taxes or carbon fees.

WSDOT might also receive more federal money if Congress passes President Biden’s $2.3 trillion American Jobs Plan, which includes a promise to modernize 10,000 bridges and 20,000 miles of roadways.

Regardless of whether those plans materialize, Gov. Jay Inslee recommends a $429 million spending increase on preservation for the regular 2021-23 state transportation budget.

Olympia’s hands have been tied by $16.5 billion in existing and planned debt — more than half of the state’s share of gasoline tax — to build massive projects like the Highway 99 tunnel, Highway 520 bridge replacement and future extensions of Highways 509 and 167 around SeaTac, Puyallup, Fife and Tacoma.

Billions more must be spent to replace fish-blocking road culverts, as required by a federal court ruling.

About 72 percent of Washington’s highways are rated in acceptable condition. That’s worse than the national average of 80 percent smooth pavement. WSDOT’s annual report, using looser criteria, shows 93 percent rated “fair” or better.