Environment officers have taken action against a homeowner who built an embankment without permission.
Natural Resources Wales (NRW) said unpermitted construction work had taken place on the bank of the River Thaw near Cowbridge.
The property owner had built a raised earth embankment around their home to protect it from flooding.
An outfall pipe had also been installed in the riverbank for drainage.
But NRW said there was a risk that the embankment could have diverted floodwater and increased the risk of flooding for neighbouring properties.
The riverbank was swiftly restored to its original state by the homeowner, who complied with a remediation notice from the environmental body.
A specialist team at NRW has investigated over 100 cases of illgeal river works across South Wales since it was formed in 2021.
They advise that people must apply for a permit from NRW if they want to work on or near a main river, a flood or sea defence or in a flood plain.
Tim England, NRW operations manager for flood management, said: "Our enforcement work across South Wales highlights the importance of regulating flood risk activities."
"We aim to educate, advise, and guide offenders while also addressing the impacts of works carried out without permission, using a range of enforcement actions to reduce the risk to people and wildlife."
"This work is an integral part of managing flood risk, helping nature to recover and making our communities more resilient to climate change."
NRW says their approach is to have constructive talks with offenders to provide advice and guidance about responsible practices to reduce the risks involved.
But some cases require interventions, such as enforcement notices, to remediate any harmful effects caused by the unpermitted activity.
Yellow Weather warning issues for Snow later this week
Decision due on wood processing plant
Carbon emissions up by 6% last year
Toddler dies after medical episode
Housing rent set to rise by 4.3%
Power tools stolen in van break-ins
New Community Cinema to launch in Llantwit Major
Three youths arrested after Penarth assault
CCTV appeal after Barry robbery
Barry: three men jailed in shoplifting crackdown
Cardiff Bay connects to heat network
Two boys guilty of Kamran Aman murder
Another successful year for Santa's Cause
Two men questioned after A48 collision
Candlelighting held at Barry chapel
