 HOUSTON, April 21, 2021 PRNewswire -- Select Energy Services, Inc. NYSE: WTTR today announced that it will release first quarter 2021 financial results on Tuesday, May 4, 2021 after the market closes. In conjunction with the release, the Company has scheduled a conference call, which will also be broadcast live over the Internet, on Wednesday, May 5, 2021 at 11:00 a.m. 