Voters in unincorporated King County could be asked to increase a levy lid to help fund roads amid a decline in revenues.

If approved by voters, the levy lid could be raised to $2.25 per $1,000 of assessed property value, which is the maximum the county is allowed to collect. Currently, the collection rate is about $1.81 per $1,000 of assessed property value. In total, the levy could generate around $164 million over eight years, or some $22 million annually. While significant, it’s far less than what is needed to fully fund the county’s roads department.

“Even if we did get $22 million it would help, but it would not solve the problem,” said King County Councilmember Kathy Lambert at an Oct. 28 meeting of the Local Services committee.

The committee directed staff to begin drafting an ordinance that could appear on the ballot during the August or November elections in 2020. Even if it passes, further funding mechanisms will have to be found.

Currently only about 11 percent of residents in the county are paying to maintain infrastructure like roads and bridges in unincorporated areas. Many areas — and their respective tax bases — already have been annexed into cities. King County Councilmember Claudia Balducci said cities would likely have to chip in to support the infrastructure in the future.

“The fix to adequate county road funding is going to be a countywide fix. There’s just no way to support the level of infrastructure need that we have entirely out of revenue from unincorporated King County,” Balducci said.

The county is projected to run out of capital funding for roads and bridges by 2025. About 80 percent of the county’s roads budget comes from property taxes from the roads levy. As the county’s tax base shrinks, property value has also risen faster than the 1 percent, which the county is allowed to raise property taxes annually.

When the county runs out of capital funding, it won’t have money for new construction and will essentially be “managing the decline,” as Lambert puts it.

Roads and bridges in unincorporated King County see an average of 1 million vehicle trips a day. Maintenance for the infrastructure is only paid for by the roughly 250,000 residents in unincorporated parts of the county. Additionally, there’s not much commercial activity outside of cities, so the county doesn’t get much sales tax.

On top of the levy, the county could ask voters to approve a taxing district, which could raise between $5 million and $10 million annually. A previous district was repealed in 2014.

However, even those wouldn’t bridge the budget gap the county is facing. To maintain and improve roads, the county needs at least an additional $250 million. If that amount isn’t found, the county could start closing rural bridges and letting roads return to gravel.

By 2040, the county predicts some 35 bridges will be either closed or have weight restrictions placed on them.