GMDA plans to install ultrasonic flow meters at STPs along with CCTV cameras to monitor flow of raw sewage December 1, 2023 | Key Segments, Municipal Wastewater, News & Developments, Tech Focus, Wastewater Gurugram Metropolitan Development Authority (GMDA) is planning to install ultrasonic flow meters at sewage treatment plants along with CCTV cameras for monitoring flow of raw sewage. This content is restricted.