 PASADENA, Calif.--BUSINESS WIRE--Tetra Tech, Inc. NASDAQ: TTEK, a leading provider of high-end consulting and engineering services, announced today the planned dates for its third quarter 2021 results and conference call. On Wednesday, July 28, 2021, after market close, Tetra Tech intends to announce its third quarter 2021 results. On Thursday, July 29, 2021, at 8:00 a.m. Pacific Time, Tetra Tech plans to host a conference call to present and discuss the Companys financial results and forw 