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CHICAGO-The West Loop's proximity near the Ogilvie Transportation Center and Union Station, furnished space and "an extremely aggressive economic package" were enough to lure Tetra Tech, Inc. from the Aon Center to 1 S. Wacker Dr. The Pasadena, CA-based engineering and technical service firm signed a lease for 26,362 sf on the 37th floor of Teachers Insurance Annuity Association's 40-story building.

The building, about two blocks from Metra's two busiest rail terminals, was a better fit for the Tetra Tech employees who commute, suggests Connor Kerr of CB Richard Ellis, who represented the company along with Lisa Konieczka. Mike Curran and Steve Smith of Jones Lang LaSalle, which has its US headquarters in Aon Center, represented TIAA. Although terms were not disclosed, recent published net lease rates at 1 S. Wacker Dr. start at $12 per sf.

Both the West Loop and East Loop have seen vacancy rates increase this year, although the 46-million-sf West Loop submarket continues to be healthier by a wider margin. Vacancy with sublease space was 16.7% in the West Loop to start the third quarter, according to Delta Associates, while the rate in the East Loop is 17.9%. While the West Loop saw 466,000 sf of positive absorption in the first half of the year, the 28-million-sf East Loop submarket was in the red by 244,000 sf, worst Downtown.