ST. LOUIS COUNTY, Mo.—Officials closed a south St. Louis County bridge already partially under construction Monday, citing rapidly deteriorating pavement in recent weeks.

For several months, crews have been working on the Bayless Avenue bridge over Gravois Creek. The hope was that a lane of traffic could stay open for the structure, while the other half was demolished and rebuilt. The bridge sees roughly 15,000 vehicles on it on weekdays 

"The driving surface of that half of the bridge that remained open to traffic significantly deteriorated in recent weeks,” said Stephanie Leon Streeter, director of Transportation and Public Works in a news release. “Patching did little to stabilize the increasingly degraded pavement. We’ve reached the point where a full closure is unavoidable.”

Work to finish the entire bridge should be done by sometime this summer.

Detours are marked in the area of Lemay Ferry Road, Reavis Barracks Road and Union Road.

Spectrum News witnessed multiple vehicles approach the closure and turn around, but also saw one motorized bike cross over the bridge