Air quality monitoring for wastewater treatment plants
Wastewater treatment processes can generate variable odour-related conditions and gaseous emissions across treatment, sludge handling and storage areas.
Aernode provides continuous monitoring around relevant process zones and site boundaries, helping operators detect changing conditions, relate events to plant activity and meteorology, investigate complaints and maintain structured environmental records for day-to-day management.
Continuous insight for proactive odour management
Conditions around wastewater treatment plants can change rapidly with process loads, sludge handling, storage activities and meteorological conditions. Continuous monitoring provides a persistent record of relevant environmental parameters, helping operators identify recurring patterns and review changing conditions around process areas, including periods associated with reported odour episodes.
With monitoring nodes positioned around relevant process areas, site boundaries and sensitive receptors, operators can relate changing conditions to plant activity and local meteorology, investigate reported odour events and identify recurring patterns. The resulting data provides a continuous environmental evidence base for operational review, mitigation actions and communication with external stakeholders.
Operational value of continuous wastewater plant monitoring
Continuous environmental data gives operators additional context to review changing conditions, investigate reported events and support day-to-day environmental management around the plant.
Continuous environmental oversight
A distributed network provides an ongoing record of selected environmental parameters around process areas and site boundaries, helping operators identify recurring patterns and variations that periodic measurements may not capture.
Better context for reported odour events
Historical measurements can be reviewed alongside plant activity and meteorological conditions to provide additional context when odour episodes are reported and support a more informed assessment of the circumstances surrounding the event.
Active monitoring with configurable alerts
Configurable thresholds can highlight changes in monitored parameters, giving operators an additional signal to review process conditions, meteorology or activities taking place in relevant areas of the plant.
Identify recurring conditions and patterns
Comparing measurements across process areas, operating periods and meteorological conditions can help reveal recurring environmental patterns and support more targeted investigation of activities or locations requiring attention.
Structured data for reporting and communication
Consistent time-series records support internal environmental reviews, documented follow-up of reported events and evidence-based communication with municipalities, neighbouring communities and other stakeholders.
A monitoring network designed around treatment processes and receptors
Each deployment is configured around relevant process areas, site boundaries, prevailing winds and nearby receptors, so measurements provide useful context for day-to-day environmental management and the review of reported events.
Define the monitoring objectives
Identify the process areas, site boundaries and nearby receptors that are most relevant to the monitoring programme, and define the environmental conditions or reported events the network should help operators review.
Configure and position the network
Select the relevant environmental parameters and position monitoring nodes around treatment, sludge handling or storage areas, taking prevailing winds, site boundaries and sensitive receptors into account.
Establish the operational workflow
Connect measurements with dashboards, configurable alerts, meteorological data and reporting outputs so operators can review changing conditions, investigate reported events and maintain a structured environmental record over time.
Parameters commonly monitored around wastewater treatment plants
| Parameter | Why it matters at wastewater treatment plants |
|---|---|
|
H₂S
Hydrogen sulphide
|
Hydrogen sulphide can be associated with anaerobic conditions in wastewater conveyance, treatment and sludge-management processes. Continuous measurements can help review concentration trends and variations around relevant areas and provide additional context when odour episodes are reported. |
|
NH₃
Ammonia
|
Ammonia may be relevant around selected treatment stages, sludge handling and storage areas. Monitoring can provide additional information on changing conditions and support comparison between operating periods or process activities. |
|
VOCs
Volatile organic compounds
|
Volatile compounds can vary with influent composition, industrial discharges, treatment processes and sludge handling. VOC monitoring can provide a broad indicator of changing volatile emissions and useful context for the investigation of recurring or reported events. |
|
PM₂.₅ / PM₁₀
Particulate matter
|
Particulate matter can be relevant where sludge handling or drying, material movements, unpaved surfaces and internal traffic contribute to local dust conditions. PM monitoring also provides a broader view of ambient air quality across the site and at its boundary. |
|
Wind
Speed and direction
|
Wind speed and direction provide essential context for interpreting measurements across the plant and its boundary, particularly when reviewing whether changing conditions may be associated with specific process areas or nearby receptors. |
Monitoring configurations are project-specific; H₂S, NH₃, VOC indicators, particulate matter and meteorological parameters are selected according to treatment processes, site characteristics and monitoring objectives.
Explore the Aernode Components
Aernode Monitors
Configurable outdoor stations for continuous measurement of particulate matter, gaseous pollutants and environmental conditions across distributed monitoring networks.
- Site-specific pollutant configurations
- Continuous outdoor data acquisition
- Designed for single-site and multi-node networks
Aernode Cloud
A central environment for device supervision, data storage, post-processing and secure access to current and historical monitoring information.
- Remote network and device management
- Historical records and data continuity
- Authenticated integration through APIs
Sensor Kits
Preconfigured sensing assemblies that simplify pollutant selection, field servicing and configuration updates throughout the operating life of the network.
- Modular pollutant combinations
- Efficient field replacement
- Configuration tailored to project requirements
Reporting Tools
Digital environments for current conditions, historical analysis, automated outputs and communication with internal teams or external stakeholders.
- Real-time and historical dashboards
- Threshold alerts and scheduled reports
- Private and stakeholder-facing environments
Accessories
Power, meteorological, mounting and connectivity options for fixed-site, perimeter and off-grid monitoring configurations.
- Weather stations and anemometers
- Solar power and autonomous deployment options
- Mounting and connectivity accessories
Frequently asked
questions
Practical answers on wastewater odour-related conditions, H₂S monitoring, network design, complaint investigation and continuous environmental monitoring around treatment plants.
What causes odour at wastewater treatment plants?
Odour at wastewater treatment plants can arise when volatile or reduced compounds are generated or released during wastewater conveyance, treatment and sludge-management activities.
Hydrogen sulphide is one of the most common odour-related compounds, but ammonia, volatile organic compounds and other reduced sulphur compounds can also contribute depending on the influent and treatment process.
Conditions can change with wastewater load, septicity, temperature, retention time, sludge handling, maintenance activities and process upsets. For this reason, odour management is usually approached as a site- and process-specific problem rather than being associated with one pollutant or one treatment stage.
Which gases are commonly monitored for wastewater treatment plant odour?
Hydrogen sulphide (H₂S) is commonly monitored because it is strongly associated with anaerobic or septic conditions and is frequently relevant to odour episodes at wastewater facilities.
Ammonia (NH₃) and VOC indicators can provide additional context where sludge treatment, industrial influent or other process conditions may produce a broader mixture of volatile compounds.
Wind speed and direction are also important because they help relate concentration changes to process areas, site boundaries and nearby receptors. Aernode Sensor Kits can be configured with different combinations of gas and environmental sensors according to the treatment process, expected concentration range and monitoring objective.
Is hydrogen sulphide monitoring alone enough to understand wastewater odour events?
Not always. H₂S is an important indicator at many wastewater treatment plants, but an odour episode can involve a mixture of compounds and the perceived odour impact cannot be represented by a single gas concentration in every situation.
Combining H₂S with other relevant indicators such as NH₃ or VOC measurements, meteorological data and plant operating records provides a more complete basis for investigating changing conditions.
Chemical sensor measurements should therefore be treated as environmental evidence and process indicators rather than as a direct measurement of human odour perception.
Where should air quality monitors be positioned at a wastewater treatment plant?
Monitoring locations should be selected according to the process areas most likely to generate relevant emissions, the site boundary, prevailing and variable wind directions, and the location of nearby sensitive receptors.
Depending on the plant, relevant areas can include the inlet or pretreatment stage, primary treatment, sludge thickening and dewatering, storage areas, digestion-related processes and odour-control systems.
A distributed network can combine process-area nodes with boundary or receptor-oriented locations so operators can compare conditions across the site. Placement should follow the monitoring objective and the source-pathway-receptor relationship rather than simply spacing instruments evenly around the plant.
Aernode Accessories include meteorological and deployment options that can support network design and interpretation.
How can continuous monitoring help investigate odour complaints from nearby communities?
Continuous monitoring creates a time-resolved record that can be reviewed when an odour complaint is received.
Operators can compare the reported time and location with H₂S or other monitored parameters, wind direction, measurements from different nodes and relevant plant activities.
This does not by itself prove the source of an odour, but it can provide substantially more context than a measurement taken after the event has passed.
Aernode Cloud can preserve current and historical monitoring data, while Reporting Tools can support event review, recurring-pattern analysis and structured records for internal follow-up or stakeholder communication.
How can continuous monitoring support an Odour Management Plan?
An Odour Management Plan typically relies on a combination of process controls, operating records, complaint management, site inspections, weather information and monitoring where appropriate. Continuous environmental measurements can add an objective time-series record to this workflow.
The data can help document recurring conditions, review events against process activity and meteorology, configure operational alerts and maintain evidence of follow-up actions over time.
The monitoring network should be configured around the site-specific odour sources, pathways and sensitive receptors identified in the management plan.
Aernode Reporting Tools can support historical analysis, configurable outputs and structured reporting workflows.
Can continuous sensor monitoring replace olfactometry or formal odour assessment?
No. Continuous gas and environmental monitoring provides chemical-indicator and contextual data, but it does not directly measure odour concentration as perceived by people.
It should therefore not be presented as a substitute for dilution olfactometry, formal odour surveys or other assessment methods required by permits or applicable regulation.
Aernode air quality monitors are intended for continuous indicative and supplementary environmental monitoring. Their role is to provide persistent data that can complement formal assessment methods, support operational investigation and help determine when more targeted sampling or specialist odour assessment may be appropriate.
LEARN MORE
Explore technical resources
Plan a monitoring network for your wastewater treatment plant
Define the right environmental parameters, node placement, connectivity and reporting workflow for continuous monitoring across process areas, site boundaries and nearby receptors.