The wonder of wetlands: Nature’s helping hand in reducing pollution

Water – it’s one of our most basic needs, vital to the survival of every living creature.

But in the face of both climate and nature emergencies, and under the demands of modern society, the pressure on our most precious resource is becoming more and more evident. 

As levels of industrial pollution have decreased, water quality in our rivers has improved. But still only 40% are meeting good or excellent quality status.

There has never been such strong support for our rivers, and across Wales businesses, industries and communities are all pulling together to seek solutions to further reduce pollution sources.

And while significant investment in infrastructure and technology will no doubt be an important driver for change, businesses are also looking to nature-based solutions to help achieve the clean waters we want.

Wetlands – more than just a pretty sight

Wetlands to remove pollution, particularly nutrients, from wastewater have been trialled as far back as the 1950s. Evidence shows that they can be effective at reducing levels of phosphorus, nitrates and ammonia – all of which can harm the health of a river.

Offering a more sustainable alternative to traditional infrastructure, water companies and other industries are now looking to trial wetlands as part of their treatment systems.

We refer to these engineered eco-systems as ‘constructed wetlands.’ The wetland’s plant, microbe and substrate systems naturally treat wastewater, removing pollutants and allowing the cleaner water to be returned to a river, stream or estuary.

A constructed wetland providing wastewater treatment can also provide other benefits to the environment and our communities.

They can create much-needed habitat for biodiversity, act at a carbon sink and control the surface water flows.

Constructed wetlands can be built for biodiversity, flow control or treatment. In addition to the purpose they are designed for, they will offer the other benefits if designed correctly.

Depending on their location and purpose, they can also provide calm and tranquil spaces for people to get close to nature.

The right solution, in the right place

Going forward, using nature’s helping hand to deal with pollution will be an important shift in dealing with the problem, but not the silver bullet.

This was reinforced by the First Minister in the first River Pollution Summit held last year, which brought leaders from all sectors together to pledge to take action to reduce river pollution.

As Wales’s environmental regulator, we are currently considering what permissions and controls will need to be put in place to protect the environment, as more businesses and industries seek out sustainable solutions to wastewater treatment.

We are considering how to regulate such systems to ensure they operate effectively to treat wastewater and achieve clear environmental benefits without any higher level of risk than traditional treatment methods.

Of course not every location and effluent will be suitable for a constructed wetland. Consideration needs to be given to the type of pollutant and all available treatment options, before concluding that a constructed wetland for treatment is a feasible solution. It will need to provide the right levels of environmental controls and have any permissions required to prevent harm to the environment or human health.

Assurances will be needed that constructed wetlands are maintained and managed effectively by those responsible, to ensure they do no alleviate one problem, only to cause another.

Industry experts are preparing to reconvene for a second River Pollution Summit, where progress against actions will be mapped and best practice shared. Nature-based solutions will once again be brought to the fore as leaders come together to work towards a shared ambition to restore our rivers for wildlife, for our communities and future generations.

You can find out more about how NRW is tackling river pollution through the Wales Better River Quality Taskforce on the Welsh Government website.