Water Quality Monitoring: From Crisis to Control

But, even the best crisis response plan can be impaired if the right technologies are not in place. That's where remote water quality monitoring comes in: it is the key to mitigating the risk of contaminated water reaching consumers.

Remote water quality monitoring provides 24/7 insight into the quality of water flowing into plants and through the distribution system. If contaminants are detected, the utility is alerted instantly. When combined with analytics and trend monitoring software, utilities can go beyond detecting known contaminants for a comprehensive understanding of how their water composition changes. When it exceeds normal parameters, the utility is notified.

Water Quality Risks From Source to Tap

The quality of source water can be affected by many different types of threats. These can be naturally occurring, such as high levels of nitrates from stormwater runoff or a toxic algal bloom triggered by unseasonal weather; or they can be manmade, such as a chemical spill or illegal dumping of waste or industrial effluent.

Contamination events can occur within the distribution system as well. Typically, these are the unintended results of human intervention. Maintenance activity—such as flushing or pipe repair, or the sudden increase in pressure and flow from firefighting activities—can disrupt the biofilm in the pipe network. Operator errors, such as leaving a valve open, can allow untreated water to enter the system.

Lastly, water utilities must be aware of the potential for malicious attacks. Although rare, the intentional disruption of critical water infrastructure by bad actors is something water utilities must be prepared for.

Monitoring in the Moment

The first step in responding to a crisis is knowing that something is wrong. While random grab samples can provide this information, it can take hours or even days to get results, which delays the water utility's response.

With real-time water quality monitoring and reporting, utilities receive updates on water composition at regular intervals. By placing monitoring stations in strategic locations throughout the network, operators can be alerted when parameters shift or certain contaminants are detected.

Recent advancements in water quality monitoring provide distinct advantages. Reagent-free systems, for example, offer reduced costs and maintenance, since they don't rely on testing agents that run out or expire. Reagent-free systems can also test for far more substances—even those outside of a fixed set of parameters. For example, spectral analyzers can take a fingerprint of the water by measuring UV light between 190 nm and 760 nm. This can then be compared to historical results to detect changes that may not be noticeable when monitoring for standard parameters, including a wide range of industrial substances and uncommon pollutants.

Fingerprint analysis can even be leveraged for trend monitoring, allowing water utilities to detect patterns in changing water composition over time. Even when such changes are not a public health concern, they can be used to adjust water treatment parameters and provide more consistent water quality year-round.

Planning for Action

A robust water quality monitoring program is an essential first step to effective crisis response and a key component of a comprehensive action plan. Such plans should include the following steps:

1. Validate the alarm.
   

   Utility managers must determine whether the alert indicates a true event or a false alarm. This may require going to the sensor’s location and pulling a grab sample for lab testing.

2. Assess the impact.
   

   If the alarm is validated, utility managers must evaluate the scope of the impact and whether it is localized within the distribution system or widespread.

3. Communicate with stakeholders.
   

   Affected customers must be notified, as well as regulatory agencies and other relevant stakeholders. The utility must provide information regarding the situation, potential health risks and any necessary precautions.

4. Take corrective action.
   

   The utility must develop a remediation plan to address the contamination and/or its source. This includes identifying the root cause and, if possible, measures to prevent recurrence.

Through a comprehensive crisis response plan and remote water quality monitoring, water utilities can strengthen their ability to mitigate contamination events, safeguard public health and uphold the integrity of the water supply system.