Landowners in Wales are being urged to seek expert guidance before carrying out any work in rivers or streams to avoid costly mistakes, accidental damage, and environmental harm that can be difficult to reverse.

Natural Resources Wales (NRW) has issued a warning that poorly planned activities – such as removing gravel, reshaping banks, or straightening channels – can create new problems, including increased erosion, higher flood risk, and harm to fish, plants, and other wildlife. Such work can also affect neighbouring land and structures, potentially leading to legal liability and expensive repairs.

NRW says many of these issues could be avoided if landowners checked with them before starting any work. Proper planning and professional advice can help landowners understand the permissions required, ensure the work is carried out legally, and protect both the environment and their property.

Francesca Sanchez, Specialist Advisor for Freshwater Habitats and Species at NRW, said: “We’re asking landowners to get in touch with us before they start any work in a river or stream. It’s genuinely in their best interest to do so. Far too often, we hear about these activities only after something has gone wrong, and by that point landowners could face stop notices, costly restoration and enforcement action. A simple call at the start could prevent all of that.

She continued: “We want to help landowners do things properly – in a way that protects their land, avoids damage to wildlife and doesn’t create problems for their neighbours. Getting it right first time is always easier and cheaper than putting it right afterwards.”

Natural features such as gravel shoals have already declined by more than half in Wales over the last century. These features are vital habitats for fish, invertebrates, and other wildlife, and they play an important role in maintaining the stability and health of rivers and streams. Removing or disturbing them can have long-term consequences, including destabilising the surrounding environment for years, reducing biodiversity, and altering the natural flow of water. In some cases, poorly planned work can also lead to enforcement action against the landowner.

Most work in the channel or beside a river or stream needs permission from NRW or the local authority, and carrying out work without a permit or consent could be an offence. NRW officers are on hand to provide expert guidance on what permissions are required and advise landowners on the most appropriate and sustainable way to proceed.

Ms Sanchez added: “It’s always better to check what permissions you need before you carry out any work in a river or stream. It’s better for nature and for the landowner.”

“We can guide you through what’s needed and help you avoid accidental damage and enforcement action,” she said.

Landowners who are planning any work in a river or stream are encouraged to contact NRW)for advice before starting. Advice can be obtained by calling the number 0300 065 3000 or by emailing [email protected]

Suspected illegal activity in rivers can be reported to the same number.