 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 fourth quarter and fiscal 2021 results and conference call. On Wednesday, November 17, 2021, after market close, Tetra Tech intends to announce its fourth quarter and fiscal 2021 results. On Thursday, November 18, 2021, at 8:00 a.m. Pacific Time, Tetra Tech plans to host a conference call to present and discuss the Comp 