The main challenges in these programs generally revolve around the remoteness of the monitoring sites and the harsh conditions that the monitoring equipment are installed in. Some sites are a more than 2-hour drive from the WQI’s nearest regional sampling contractor. Other sites are regularly cut off by flood waters for days at a time.
In these circumstances, there is no practical way for manual sampling (a.k.a. bottle and pole sampling) to be able to accurately capture a run-off/flood event. This necessitates the use of automated sampling systems.
Because of the on-site conditions, any automatically collected samples also need to be preserved on site (as well as is possible), to ensure their integrity.
Ambient air temperatures can be more than 40 ◦C (104 ◦F), and up to 55 ◦C (131 ◦F) inside the monitoring huts (typically a 2×2 m, cyclone rated shed). Humidity also can be extremely high.
Samples that are not refrigerated in these circumstances are not considered to be representative of the waterway, and typically are not analysed.
The primary concern with the equipment is the environment they are installed in. The monitoring huts are ventilated to allow airflow. This means that dust and small animals can find ways into the huts as well. The risk of snakes means that care must be taken when working in the huts.
The high humidity often results in the refrigerated samplers generating large amounts of condensation, on both the inside and the outside of the refrigeration unit.
This means that the plug in the base of the sampler has to be removed permanently. Otherwise, the sampler fridge can start to fill with condensation.
The samplers themselves are kept on a slatted bench, or elevated slightly off the ground, to ensure good drainage of water.