Utilising a Diverse Approach for Continuous Water Quality Monitoring

How has the introduction of Section-82 influenced the technical expectations for Continuous Water Quality Monitoring?

The introduction of Section-82 has significantly increased expectations on water and sewerage companies to monitor the impact of effluents from discharges and outfalls on local water courses. The introduction of Section-82 mandates companies to continuously monitor water quality both upstream and downstream of discharges and outfalls into water courses, providing continuous, near real-time data, highlighting the impacts of discharges on the receiving water course by use of continuous monitoring of key indicator parameters, including pH, Temperature, Turbidity, Dissolved Oxygen and Ammonia*. 

Data from CWQM should then be used for informing and influencing investment strategies, helping to reduce the number of discharges and the impact of these on local watercourses.

*Ammonia levels can be derived from Ammonium, temperature and pH values.

What level of data quality, validation, and governance do you think Section-82 will ultimately demand? 

Data from continuous water quality monitoring needs to be as reliable as possible, as it will be used by Water and Sewerage Companies (WaSC’s) to inform future investment decisions; however, the quality of results obtained from sensors will be reliant on optimal siting of monitoring systems, effective equipment maintenance and reliable calibration of water quality sensors. Data will also need to be verified and validated, as sensor drift between maintenance visits can occur, especially in Ammonium sensors, or if sensors are placed in areas of high turbidity, this can lead to sensor fouling issues, which may also affect readings, leading to unreliable results. Any sensor issues or monitoring downtime should be clearly documented on the data systems.

Water quality data needs to be presented in a format which can be easily interpreted and displayed with other sources of available data, such as that from Event Duration Monitors (EDMs), rainfall data, flow and level data and information around local land use. All of this information will provide WaSC’s with a full picture of what is happening in and around the area of monitoring. As all data from Section-82 CWQM should be made publicly available in near real-time, this data also needs to be presented clearly and concisely to enable easy interpretation.

All data relating to Section-82 monitoring will also need to be stored and managed in accordance with information security and quality management standards.

From a technical standpoint, what are the biggest advantages of continuous monitoring over traditional sampling? 

The biggest advantages of continuous monitoring over traditional spot sampling are that you get a continuous and near real-time picture of water quality, which means you can identify changes to water quality as they occur, identify pollution events and use this data to detect long-term trends.
 
Taking spot samples only gives you a snapshot of water quality at the time of sampling, often missing changes in water quality as they may not occur at the time of sampling. However, spot sampling can also be incredibly useful, especially when carried out in conjunction with CWQM, as many more parameters can be tested for than those that can currently be detected by water quality sensors, such as pesticides or heavy metals.

Continuous monitoring generates vast amounts of data. How important is translating this into operational insights, and how can Tetra Tech help utilities turn raw data into actionable network intelligence? 

The data from continuous water quality monitoring will give valuable insight into the impact of discharges from storm overflows on water courses, and turning those numbers into insightful information will help provide water and sewerage companies with fully verified and reliable data for informing investment decision-making. The data collected will also help inform maintenance planning, enabling a more proactive approach to maintenance and calibration of equipment.

With Tetra Tech’s cloud-based platform- HydroWeb™, we can offer seamless data visualisation and integration with third-party systems, ensuring full data transparency, empowering users to make informed decisions around the maintenance of assets and the impacts of storm overflows on the receiving water courses and therefore prioritise investment where it is most needed.

How do you see AI, machine learning, and predictive analytics shaping water quality management, and what role could Tetra Tech’s digital optimisation tools play in detecting anomalies and forecasting risks? 

AI, ML and predictive analytics will help improve CWQM by automating data analysis, allowing faster detection of anomalies and delivering predictive water quality models, helping to deliver more proactive and cost-effective investment decision-making.

HydroWeb™ is designed to store and visualise data from continuous water quality monitoring installations, EDM, and more. Data can be clearly visualised and easily downloaded for reporting requirements. Alarms and alerts can be set for parameter thresholds, loss of data or transmission issues. Our HyrdoWeb™ user-friendly platform also offers AI optimisation, digital twins and ML insights, helping users to make informed decisions in real-time, helping to reduce the number of pollution events and mitigate the impacts of discharges on receiving watercourses.

How can Section-82 monitoring help water companies prioritise investment and improve environmental performance?

The programmes of work to install, monitor and maintain continuous water quality monitoring systems around the 27,500 storm overflows in England will require significant levels of investment from water and sewerage companies, the data received from each monitor will then help water companies to identify where issues arise and therefore inform investment decisions, prioritising those sites where water courses are most impacted by discharges from sewer overflows. However, we must also remember that many pollution incidents that impact water courses may not solely be caused by WaSC’s, and the continuous water quality monitoring accomplished under Section-82 could also highlight other areas of water course pollution, and therefore, more sectors may also need to work to minimise the impact of their effluents on the local water environment.

What barriers do utilities face when deploying new monitoring solutions at scale, and how could Tetra Tech’s combined engineering, environmental, and technology expertise help overcome these? 

The size, cost and complexity of Section-82 monitoring will be a big challenge for all water and sewerage companies, with around 27,500 overflows to be monitored throughout England. That’s a vast number of installations to plan, install and then maintain throughout AMP8 and AMP9. 

Some of the toughest challenges will be around gaining land access to enable installations of continuous monitoring equipment in the optimal location for ensuring robust water quality results. Aside from this, equipment will need to be thoroughly maintained and regularly calibrated to ensure reliable results from water quality sensors.

As specialists in supporting water utility companies, Tetra Tech has developed tailored solutions for continuous water quality monitoring for each client. We are equipment agnostic, providing plug-and-play systems to meet client requirements. We work to provide detailed solutions for each stage of the Section-82 scope, from planning & access, installations, equipment maintenance, sensor calibration and data visualisation and analytics. We provide complete Section-82 compliance services with turnkey, scalable and adaptable solutions and highly experienced technical support.

With support functions in planning, water quality modelling, flow & level monitoring and water quality sampling & analysis, Tetra Tech can provide complete end-to-end support for all Section-82 requirements.

Aside from Section-82, what other areas of CWQM can Tetra Tech provide help with?

Our teams can also provide the same high standard of end-to-end solutions for other areas where CWQM may be required, such as highways runoff, construction, environmental monitoring and more. We have strong experience in all areas of water quality monitoring including auto sampling, sample analysis, flow and rainfall monitoring and more to help provide companies with a robust water quality monitoring solution ensuring collection of meaningful water quality data which can help to show compliance with discharge consents or inform decision making and investment planning.

With decades of expertise and a principle of leading with science, Tetra Tech is developing unique and innovative solutions that will be instrumental in supporting the industry to reaching its regulatory targets. By collaborating with Tetra Tech, you can navigate rising challenges, and be one step ahead, becoming a leader in the race to create a more sustainable future.