The City of Sumner’s plans to turn its now defunct golf course west of East Valley Highway into a major warehouse site have drawn it and Auburn’s leaders into effecting a likely readjustment to a small part of their mutual city limits.

Pablo Para, a traffic engineer for the City of Auburn, said this week that that would make sense because part of the development plan calls for changes to the access at Stewart Road to improve circulation and safety for the warehousing site.

Also, Para said, most of the development that is to be served by that section of the revamped Stewart Road project is entirely within the city of Sumner.

“And it would help to create a better delineation in terms of maintenance responsibility and emergency response for the cities to modify the boundaries in that area,” Para said.

City engineers expect the interlocal agreement and the boundary adjustment to come before the Auburn City Council for a vote within a month, possibly as early as next Monday’s regular meeting.

“Sumner does have a tight timeline for trying to close on the property for the Sumner Golf Course, so we are trying to help them reach that goal,” said Ingrid Gaub, assistant director of engineering for the City of Auburn.

For more than a year, staff members of both cities have been coordinating with the site developer to review the proposal and, Para said, to “offer recommendations for a safe and efficient corridor.”

According to the proposed agreement, the City of Auburn would not be responsible — or liable for — any of the roadway infrastructure west of the Lake Tapps Parkway bridge, or for a new traffic signal to serve the proposed warehouse site.

As for the City of Sumner, it would provide access easements and an improved materials storage site to the City of Auburn for snow and ice response to the Lake Tapps Parkway.

Auburn Council members discussed the boundary adjustment Monday evening in a study session at City Hall.

Councilman Wayne Osborne wanted to know whether a transportation impact study had been done, spelling out the potential impact the warehouse site would have on transportation.

“We have done a traffic analysis of that corridor with the development of the golf course and that corridor will go into service level F, and we’re looking at putting another bridge in at 24th Street on the south side of the golf course to relieve some of that. We’re working very hard on replacing that bridge that connects to a two-lane bridge over the river. We have design money and right of way money for that project,” said Mike Dahlem, City engineer for Sumner.

Service Level F means that every vehicle moves in lockstep with the vehicle in front of it, requiring frequent slowing.

“We’re also working with the City of Pacific to widen the rail crossing,” Dalham said. “Right now, we’re replacing the signal and rebuilding Valentine Road, so that signal will be a lot more efficient. Pacific is also widening its stretch between State Route 167 and Valentine. The state is adding an HOV lane all the way down to 8th Street, so that should relieve some congestion there.”