Waste management in the age of climate change

The odour problems of landfills, composting sites, transfer stations and biogas plants have long been a known operational challenge. In recent years, however, the rules of the game have changed.

Longer heatwaves, periods of drought and sudden heavy downpours alternate and affect every stage of waste management, so it is especially important that waste management facilities do not merely react to complaints once they arise, but prepare in advance for periods of increased odour load.

Why is waste management one of the most sensitive areas?

The odour of waste containing organic matter is essentially a product of microbial decomposition. This process intensifies further at higher temperatures.

Decomposition speeds up, so the same quantity of waste releases odour faster and with greater intensity.

Oxygen-free (anaerobic) zones form more quickly in piles, deposited layers and storage units, and these produce the most unpleasant compounds (hydrogen sulphide, mercaptans, volatile fatty acids, amines).

Leachate and sewage sludge also ferment sooner, so volatile components escape into the air more easily.

During a heatwave, therefore, the usual process can cause several times the odour load of an average spring day.

The effects of climate change at individual points of waste management

Transfer stations, collection areas, refuse collection vehicles

In summer heat, organic waste starts to ferment within days or even hours. Any extension of storage time (for example a short shutdown or a transport disruption) means an odour peak.

Composting

Composting is a heat-generating process to begin with, and in a heatwave the system is easily thrown off balance. Drying piles require more frequent watering, but over-watered or compacted areas become oxygen-deficient. Sudden heavy rain also intensifies the odour of open composting areas, and the leachate has to be treated.

Landfills

Landfill gas (methane, carbon dioxide and trace gases) generation increases in warm weather, and summer changes in air pressure and temperature affect how the gas reaches the surface. Extreme rainfall also increases cracking of the cover layer and the load on the leachate network.

Biogas plants and facilities receiving organic waste

The reception area, the handling of solid and liquid feedstocks and the storage of digestate are particularly odour-intensive points in hot weather.

The surroundings react differently too

The situation worsens not only at the odour source but also on the receiving side:

Open windows, time spent outdoors: in a heatwave people spend more time outside and air their homes, so the same odour load reaches more people.

Stagnant, windless weather: at night and early in the morning the odour does not dilute but stays close to the ground and can travel further. Persistent weather patterns, which are becoming more frequent, favour this.

Extreme rainfall: heavy rain falling suddenly after a drought can cause an immediate odour peak in storage units, leachate collectors and the sewer network.

Problems to address in waste management

A source of odours and greenhouse gases

The decomposition of organic waste produces not only odour but also methane, which in the short term is a far more potent greenhouse gas than carbon dioxide. Whatever reduces one emission - such as faster covering, efficient gas collection, proper aeration or shorter storage time - often reduces the other as well. Odour management can therefore also contribute to climate protection goals.

Seasonal and more concentrated complaints

The most severe problems may appear in the summer peak, but peak periods may well occur several times a year. Odour management must prepare in good time for the worst-case scenario too, as tensions caused by odour complaints can quickly turn into a matter for the authorities.

Declining tolerance among residents

Residential areas are expanding, environmental awareness is growing, and public sentiment around waste management facilities is particularly sensitive.

Tightening regulatory and social expectations

Expectations regarding the treatment of organic waste, the management of landfill gas and the reduction of emissions are likely to become even stricter.

Those who prepare in advance can make better decisions, use suitable and well-functioning technologies and do not have to rush into a quick fix under pressure that requires a larger investment.

What can a waste management facility do?

Prepare for the summer peak in good time! The odour control system must perform on the busiest, hottest days too, not just in average periods.

Shorten storage time! Organic waste should be processed or covered as soon as possible, especially in a heatwave.

Covering, enclosed spaces, air treatment. Enclosing and extracting reception halls, storage units and digestate stores, and treating the exhaust air, is the most targeted intervention.

Measure, do not estimate! Olfactometric measurement shows not only the odour concentration but also the character of the odour. It is worth measuring in different seasons and under different load conditions.

Address the character of the odour too! It is not only odour concentration that matters: if a foul, heavy odour is transformed into a milder, less disturbing one, residents' perception improves as well. This is what odour-neutralising technologies, such as osmogenic barrier systems, are designed for.

Take care of maintenance! Equipment is also under increased strain in the heat, so regular inspection is essential.

Be open towards the local community! Rapid handling of complaints, transparent data and regular dialogue can prevent conflicts.

Deliberate preparation for climate change

In the waste management of the future, effective odour management is not an afterthought but an important element of environmentally conscious operation that is prepared for climate change. By combining prevention, measurement and targeted technological solutions, odour load can be reduced permanently and verifiably.

Climate change does not create new types of waste, but it amplifies existing odour sources and makes the surroundings more sensitive. For waste management facilities, odour management is therefore no longer a negligible task but an important part of an operating strategy adapted to the current climate situation.

Those who gain the most are the ones who, based on measurement and taking the worst-case scenario into account, plan their odour management strategy for the long term.