When we think of noise pollution, thoughts usually go first to its impact on humans – frustrations living near busy roads or flight paths, for example.
However as developed land begins to encroach more on space shared with various forms of wildlife, the impact noise can have on them must be considered. Ashley Shepherd, Principal Acoustic Consultant here at Tetra Tech, who specialises in the impact noise can have on water birds, shares his thoughts on the current issues which need consideration.
How is noise pollution affecting ecology and is it getting worse?
The UK is reaching its capacity for new buildings and the search for suitable sites – either for industrial, commercial, or residential use – is pushing developers towards the coast, particularly for industrial or logistics plants which need a large square footage.
These coastal regions are full of wading water bird colonies, which have spent years feeding and nesting there, and any significant changes to their environment can be hugely detrimental.
Whilst many birds can get used to new sounds over time – particularly when they are continuous or regular – however, the sudden and very loud noises made typically during the construction phase of a development is particularly disturbing. And once an industrial site is completed, general operations and HGVs can all cause high levels of disturbance.
In worst case scenarios, noise pollution can cause wading water bird colonies to relocate or cause such disruption that they don’t nest or breed. This can severely disturb the populations of, in some cases, already near threatened species like curlews and black-tailed godwits.
What should clients be aware of with regard to noise pollution?
For successful management of noise pollution, consideration needs to be built into design from the very earliest stages – both to mitigate construction sounds and when the asset is complete.
Noise pollution is measured in decibels, with high levels above 75dB, medium between 55dB and 70dB and low levels below 55dB. We aim to design sites around this lower end of the spectrum, for example using other infrastructure as physical mitigation to reduce noise, planning major works outside of key breeding times, or working with clients to create detailed operational noise management plans ready for when the building is in use.
However, unless acoustic and ecology experts are engaged in a site from the beginning, it can often be too late to factor in changes that will make any real difference. As a multi-disciplinary firm, our team’s advice is often sought on Tetra Tech projects elsewhere in the business, as all our consultants are aware of the need to consider impact on ecology. However, this isn’t necessarily practised industry-wide, and for clients keen to ensure they create the most sustainable assets, it is important to specifically input into the design to prevent disturbance from noise.
Are there any rules or legislations that try to mitigate the effect of noise pollution on ecology?
At the moment, there is no legislation controlling the levels of noise pollution created by new developments, with respect to ecological receptors, only suggestions from Natural England, or guides of best practice, such as the TIDE Waterbird Disturbance & Mitigation Toolkit. These are also only focused on water birds, and there’s even less clarity around how to protect other species who may be similarly affected.
This has got to change. While we can advise as best as possible about the potential disturbance to local ecology – and once aware, many developers do want to do all they can to support wildlife – without sufficient legislation and more research into the effect of noise on other species, this will not become an industry standard. Until this comes into play, there needs to be a concerted effort from all – consultants, clients and contractors – to be aware of the risk of noise pollution on habitats and factor it into design as standard, regardless of legal requirements.