Eight months after the Washington Street bridge reopened, contractors for Kansas City Southern Railway are back working on the tunnel area, performing what some city officials believe might be the first of many periodic maintenance visits to the railroad property, and one lane for vehicular traffic is blocked.

KCS spokesman Kevin Mcintosh said workers are improving the drainage around the tunnel, using grout to fill in voids around the tunnel and correcting erosion problems caused by Tropical Storm Isaac. KCS is paying for the work.

He would not say when the project would be completed, answering in an email, “There is no specific time line for completion.”

He would not identify the contractors working on the project, but employees for Hurk Underground Technologies Inc. of Altoona, Iowa, a company specializing in subsurface and railroad drainage projects, and Key Construction of Wichita, Kan., were working at the site Tuesday.

In the eight months since South Washington reopened in February, traffic on the street from Lee Street south to Ameristar Casino has been unrestricted for about 24 days. Traffic was limited to one lane for about seven months, from Feb. 27 to Oct. 3, while a section of the street south of the tunnel was repaired.

Interim Public Works Director Garnet Van Norman said the KCS project should solve the drainage problem, but added, “I believe they’re going to keep watching it and doing maintenance because of the steep slopes. They can’t afford to have that tunnel closed.”

Van Norman said the city had no erosion problems from Isaac in the South Washington Street area.

“Whatever they did over there for drainage didn’t work,” he said. “The surface water from the rain that fell on the tunnel’s east and south sides caused problems along the railroad tracks. Now they’ve got to go in and get it fixed.”

He said the city has no control over the tunnel area. “That’s railroad property and we can’t go on it,” he said. “They’re responsible for everything, including cutting the grass.”

Washington Street was closed for three years, from 2009 to Feb. 13, after erosion threatened to collapse the then-83-year-old Washington Street bridge, which was demolished to make way for the tunnel. Erosion continued to be a problem while the tunnel was being built, forcing Kanza Construction Co., the project subcontractor, and KCS to ask the Board of Mayor and Aldermen for more time to complete the project.

Two weeks after Washington Street reopened, city officials blocked one lane of traffic south of the bridge and rerouted 18-wheelers and other heavy trucks and buses after city workers repairing a water line saw problems with a retaining wall caused by unstable soil. The problem also damaged a section of the street.

“South Washington Street sits on a ridge,” said North Ward Alderman Michael Mayfield. “We’ve had problems with soil sloughing off for years. I think Kansas City Southern will continue to look at that area and will be doing maintenance from time to time.”

He added the city will also have to continue to watch the area.

Mayor Paul Winfield agreed.

“We’ll have to constantly monitor it,” he said.