YAKIMA, Wash. -- Yakima County plans to spend at least $700,000 over the next two years planning a major new road through north Terrace Heights and a bridge across the Yakima River.

The route would offer an alternative to increasingly heavy traffic on Terrace Heights Drive and dovetails with city plans to develop the former Boise Cascade mill property.

Eventually, the road could stretch from North 57th Street in Terrace Heights through the city to Highway 12 in northwest Yakima.

Cost of the overall project is unknown.

The route has been talked about for years, but it has never moved beyond the conceptual stage.

Now the county plans to develop plans for a part of the project, specifically the section between the Yakima River and North 33rd Street.

Yakima County Engineer Gary Ekstedt said actually building the new street and bridge depends on funding and could be up to 20 years away.

The more immediate work will focus on identifying a right of way and the environmental impacts, he said.

"There will be a big public involvement component to this," he said.

The county already has right of way dedicated for the section from 33rd Street to North 57th Street.

At the same time, the city of Yakima expects to start developing plans for the south 30 acres of the former mill's 224-acre site, said Michael Morales, the city's deputy community and economic development director.

"We plan to kick around some options for construction and location of facilities," Morales said.

The century-old mill property is considered a prime area for a mix of retail, commercial, residential and light industrial development.

The mill closed in 2006, and owners are using the property to chip wood.

County Commissioner Mike Leita said the streets and development opportunities at the old mill pose a complicated mix of transportation and environmental issues that will be resolved over time.

"We want to be very deliberate and thorough in our process here," he said. "But we anticipate being successful in getting this project completed."

* David Lester can be reached at 509-577-7674 or dlester@yakimaherald.com.