What device is used for checking water flow to consumers?

The water meter is the device used for checking water flow to consumers. It measures the volume of water that passes through it in a given time period and provides data that utility companies use to bill customers based on their actual water usage. This measurement is crucial for managing and monitoring water consumption, ensuring accurate billing, and planning for future water supply needs. Additionally, water meters can help in detecting leaks or unusual consumption patterns in the distribution system, which is important for maintaining efficiency and sustainability in water resource management.

Other devices mentioned in the choices serve different functions, such as analyzing water quality or measuring specific parameters like pressure, but they do not measure the amount of water flowing to consumers.