 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 first quarter 2021 results and conference call. On Wednesday, January 27, 2021, after market close, Tetra Tech intends to announce its first quarter 2021 results. On Thursday, January 28, 2021, at 8:00 a.m. Pacific Time, Tetra Tech plans to host a conference call to present and discuss the Companys financial results an 