Hach Company - Flow Products and Services, including our legacy brands Sigma and Marsh-McBirney, has a proven track record of creating industry-leading innovations with unwavering product accuracy in the open-channel flow measurement world. Empowering you with true and timely flow data for your analysis, we dramatically reduce your risk and enable you to make critical wastewater flow decisions with absolute confidence. And smart decisions mean you're proactively managing your flow, rather than reactively dealing with problems. From state-of-the-art wireless flow loggers and industry-pioneering non-contact flow sensors, as well as our revolutionary Hach Data Delivery Services (DDS), Hach Flow is committed to providing flexible solutions for all of your flow monitoring challenges.