Building more sustainable: Environmental monitoring in construction in New Zealand

Environmental monitoring in construction is crucial for addressing issues related to noise, dust, and vibrations generated in the construction industry. In the past, measuring these parameters was done manually and infrequently, if at all.

The primary goal of environmental monitoring in construction is to ensure safe and healthy conditions for workers and residents at the worksites, while also having real-time data to manage complaints and support internal compliance.

Dempsey Wood Civil, a construction company based in New Zealand, operates primarily in the Auckland, Waikato, and Northland regions. They pride themselves on offering a wide range of activities, such as roads, dams, infrastructure, landfills, among others. They have highly skilled professionals and machinery, but above all, they are committed to the environment and the well-being of the neighbors affected by their projects. In collaboration with Adroit, a Libelium distributor in New Zealand, they have implemented an IoT environmental monitoring solution, resulting in construction sites that mitigate any disruption in the environment that may arise.

Thanks to this, Dempsey Wood Civil has managed to obtain and maintain the three most prestigious ISO quality certifications:

• ISO 45001 – Occupational Health and Safety Management
• ISO 9001 – Quality Management System
• ISO 14001 – Environmental Management System

“Adroit is one of our best distributors. They are the kind of companies that push us to go further, that push our products to their limits, and help improve our technology,” comments Daniel Sanz, Sales Area Manager at Libelium. “With such a spectacular yet challenging natural environment in New Zealand, along with the high environmental requirements of the New Zealand government, we know that if our technology can meet the end customer’s needs there, it can do it anywhere.”

Behind the change: Monitoring the environmental impact of construction

Dempsey Wood is a family-owned civil construction company that carries out various infrastructure and land development projects in the North Island of New Zealand. Their projects are often large-scale and require the use of heavy machinery at worksites located in busy residential areas. These projects are subject to strict consent limits regarding dust emissions, noise monitoring, and construction vibrations.

Maintaining a good relationship with nearby residents is crucial, as local complaints can lead to construction suspensions while issues are investigated. Wil Killip, Innovation Engineer at Dempsey Wood, emphasizes the importance of taking complaints seriously. Previously, when a complaint was received, a contractor would be called in to take measurements and produce a report. However, this process took several days and did not always satisfy both parties, as conditions could change during that time. Therefore, the shift to a real-time reporting system is very appealing to the Dempsey Wood team. “I proposed using IoT devices with sensors for dust, vibration, and noise for an initial installation. Later, we had permit issues on two other sites, so we replicated Adroit’s solution for dust, noise, and vibration in those two locations,” explains Wil Killip.

The implementation

IoT environmental monitoring solution in construction is site-specific and can be customized. It is modular, cost-effective, and scalable. The IoT solution is also portable, so Dempsey Wood can move the hardware to any site of the works to monitor specific areas. The sensors, tested in the construction industry, monitor environmental parameters such as noise, vibration, and dust. The solution can be powered by AC or solar energy. Furthermore, it is modular, allowing for easy addition of more sensors to measure other parameters such as sediment in runoff water and weather conditions.

Sensor data is transferred to the Adroit platform via the Cat-M1 network. This platform enables visualization of data through graphs, downloading .csv files, and receiving email alerts and notifications. This way, Dempsey Wood Civil can take action before construction-related disturbances escalate.

For noise pollution

To facilitate on-site compliance management, noise data can be generated as LAeq and Lmax values, which represent the average and maximum sound levels at the site. Excessive noise can cause hearing, stress and heart problems.

For Dust Monitoring

Dust sensors measure three particle sizes and thresholds can be set with alerts to the management team in the event of a violation. Its monitoring is essential to avoid respiratory health problems for workers and neighbors.

For Vibrations

Identifying the sources of vibration makes it possible to prevent possible serious damage to adjacent structures. The measurement in mm/s of the vibrations allows to calculate the level of vibration that could affect a property.

Beyond the challenge: Anticipating and mitigating environmental impact

Dempsey Wood currently has three sites utilizing Adroit’s environmental IoT solution. Wil Killip comments, “Land development is a significant part of our work. On some days, there are dry land conditions, wind, and moving machinery, so we use methods like water sprayers to control it.”

“We have received complaints from neighbors in the past, but now, thanks to the dust level control, we receive early warnings that enable us to take quick measures, such as irrigating the soil with water to mitigate it. That’s how we see the benefits of this technology,” he adds. Killip mentions that shortly after the first installation, they received a dust complaint, and the Adroit system accurately recorded it, verifying that Dempsey Wood’s site was within acceptable limits. This was possible because the noise data collected by the sensors can also generate values such as LAeq and Lmax to represent average and maximum sound levels experienced on-site. “After collaborating with us, Adroit understood that, due to the size of the projects, it was necessary to be able to move the noise sensor,” comments Killip. “When you work in a place and the wind blows in a certain direction, you want to move the sensor in that direction.”

Adroit worked with Dempsey Wood to configure the control panel according to the limits set in the project’s Resource Consent, providing an overview for staff to know when they might be nearing a threshold. Killip highlights that the control panel of the Adroit platform is “simple and easy” to use as it displays all data on a single screen, with widgets representing particles, temperature, noise, and other factors. The panel can be customized, and Adroit provided training to make the most of the dashboards.

Results

Although Dempsey Wood’s installations are recent, the reported data already provides increased confidence to the team in their operations and systems. “At this moment, I can see that our dustiest site is showing a PM10 reading of 9.16 micrograms per cubic meter, which is very low and below the maximum acceptable limit,” states Killip. “The data is quite comprehensive. It operates 24 hours a day, 7 days a week, so I have confidence that our control methods are in place to mitigate dust, and we can respond to any issues with real data. This is much better than acting blindly and simply claiming that we are not emitting anything when there is no evidence,” concludes Killip.

“The population in urban environments is growing rapidly, and this will require the construction of more services, more roads, more buildings. These constructions cause inconvenience to neighbors, so solutions like these that help prevent and mitigate these disturbances will assist regulators and administration in finding a way to grow a city without compromising the quality of life of its current inhabitants while maintaining a healthy environment,” concludes Daniel Sanz.