River water quality monitoring
Stream or river water quality monitoring programs may also involve observing and measuring water quality. In these cases, a multi-parameter water quality probe is recommended.
Multiparameter probes vary by make and model, but they share some common characteristics. As expected, multiparameter sondes typically have a range of ports for the connection of conductivity, temperature, depth, pH, dissolved oxygen, turbidity and liquid level sensors and probes. Ideally, these sensors should be replaceable in the field for immediate maintenance and system modifications. Some detectors will be equipped with built-in sensors, leaving more sensor ports for additional measurements. Most detectors contain an internal battery and memory so they can be deployed for long periods of time without regular attendance. Data loggers and external power connections allow for longer deployments, especially when the data can be accessed in real time via wireless telemetry.
Typical river water quality monitoring system
Many hydrological and water quality parameters can be measured in a stream or river, but the needs of one monitoring program can be very different from another. The number of monitoring stations, their location, and the instrumentation used at each station vary from project to project, but a general solution is based on at least one flowmeter station and associated instrumentation.
To be effective, measurement data should be provided in real time. The easiest and most effective method is to install flow measuring stations on river banks or vertical structures such as piers or bridge supports. Flow meters built around the absorber well can contain other instruments such as multiparameter sondes equipped with sensor arrays, as well as data loggers and telemetry systems. A variety of telemetry options are available, and continuous real-time data is available from any computer. This ensures that projects run smoothly and that any control measures can be immediately implemented if parameter limits are exceeded.
Jingjing
Typical river water quality monitoring systems Stilling wells are isolated reservoirs that allow river water to flow in and out, and are usually equipped with submersible pressure transducers, bubblers, or shaft encoders to measure water levels. Dissipating wells can be installed on river banks or fixed to vertical structures and can be fitted with data loggers and telemetry systems.
Integrated data logging system
The integrated data logging system is a real-time monitoring station consisting of a data logger, telemetry module and power/charging power supply. Since it is often cost-prohibitive to provide AC power to the monitored location, an integrated solar panel is used to continuously charge the 12VDC battery for autonomous operation.
Installation Precautions
1.Ensure data logging and telemetry equipment is installed sufficiently above the high water mark to prevent it from being flooded or damaged by high water.
2.Install the sensor according to the minimum expected stage. Also consider whether it will freeze in winter. If so, try to mount the sensor below the freeze line.
3.Consider the sediment problem and try to use a vertical damper if possible.
4.The sensor mounting tube should be securely attached to the stream or river bank using bottom pins so that the sensor is always re-deployed in the same location.
5.Any potentially exposed sensor cables close to the ground should be connected to the data logger box via conduit to keep animals out.