News RELEASE

Tetra Tech Signs 41,278 SF at Willow Wood Plaza in Fairfax

Fairfax, VA -- November 24, 2003: Tetra Tech, Inc. (Nasdaq: TTEK), has signed a lease amendment for 41,278 sq. ft. at Willow Wood Plaza II in Fairfax, VA. The lease included a five year and 10 month renewal of 35,891 sq. ft. as well as an expansion of their space by 5,387 sq. ft. The two-building, 244,291 sq. ft. office complex is owned and operated by investment advisory firm, KBS Realty Advisors (www.kbsrealty.com) and is currently 81% leased. KBS acquired the property in April 2000.

Tetra Tech, Inc. (www.tetratech.com) is a leading provider of consulting, engineering and technical services supporting commercial and government clients in the areas of resource management and infrastructure.  Founded in 1966 to provide engineering services related to waterways, harbors and coastal areas, this company has substantially increased the size and scope of its business and expanded its service offerings over the past 37 years through a series of strategic acquisitions and internal growth. Tetra Tech now provides environmental services, water/wastewater management, infrastructure services, communications support, and outsourcing services. At the end of fiscal year 2003, Tetra Tech had more than 8,000 employees located in more than 350 offices worldwide. The firm is based in Pasadena, California.  They have several offices in Nothern Virginia.

According to KBS Senior Vice President, Peter Potrykus, this lease was successfully executed because of the outstanding efforts of Tom Cresce and Zach Wade of Trammell Crow (www.trammellcrow.com), who represented KBS on the transaction as well as Ed Clark and Steve Hoffeditz of Transwestern (www.transwestern.net) who represented the tenant.

Headquartered in Newport Beach, CA, KBS Realty Advisors is a premier investment management firm specializing in real estate investments on behalf of select private and public pension fund, endowment and foundation partners. Founded in 1992, KBS has invested in excess of $4.5 billion on behalf of its clients. KBS specializes in purchasing and repositioning under-performing real estate and real-estate related assets in the United States.