Executive Summary

At Rhos Cefn Bryn, a Wildlife Trust reserve in Carmarthenshire, we were commissioned to transform a section of existing ditch into a functioning pond that would hold water year-round and provide a clean drinking source for conservation grazing cattle. The project required sensitive excavation, natural clay lining, and the installation of an overflow system to ensure long-term stability and ecological value while protecting the surrounding bog and SSSI habitat.

About the Client

The Wildlife Trust of South and West Wales manages Rhos Cefn Bryn, a nature reserve located south of Llwyn-teg Farm near Llannon. The site consists of unimproved, damp grassland and rhos pasture with drainage ditches and hedgerows. Much of the ground remains wet for most of the year and forms part of a wider bog complex that supports a variety of species. The Trust manages the reserve through controlled cattle grazing to maintain habitat diversity and structure.

The Challenge

The area identified for the pond was an existing drainage ditch within a boggy, semi-improved grassland that sits adjacent to an SSSI. The Wildlife Trust wanted to convert part of this ditch into a shallow pond that would provide a reliable drinking source for grazing cattle while also enhancing the wetland habitat for wildlife.

The main challenges were the saturated ground conditions, limited access, and the need to prevent rutting or soil compaction in such a sensitive environment. The pond also needed to be robust enough to withstand the weight and movement of cattle without damage. Careful planning was required to balance habitat protection with the practicalities of creating a durable, functional pond.

The Solution

We began by clearing vegetation around the working area under the watchful eye of our in-house ecologist, who supervised all clearance by hand due to the time of year. This ensured no nesting birds or protected species were disturbed and that surrounding habitats remained intact. Once the footprint was prepared, we reshaped the existing ditch into a natural basin with gentle gradients to allow livestock and wildlife to enter and exit safely.

We imported and placed locally sourced clay, which was puddled and compacted in layers to form a watertight liner. This method provided a durable, self-sealing base that blended naturally with the surrounding soil and could tolerate light poaching by cattle. To control water levels, we installed an overflow pipe that directed excess water into the adjacent ditch system, preventing flooding and erosion. We also constructed a small culvert crossing to maintain access between the two fields for ongoing grazing and management.

The Implementation

Because the site lies within a bog and includes areas of sensitive rhos habitat, we used low ground pressure machinery throughout the works to avoid soil disturbance and rutting. Our operators worked from designated routes and ground protection mats to limit vehicle movements.

All excavation, lining, and installation were completed efficiently within a short programme, despite the constraints of the site. We maintained constant communication with the Wildlife Trust’s reserves team to ensure that our methods met both ecological and operational standards.

Additional Challenges and Adaptations

During construction, we faced a period of unusually hot weather that caused the clay to dry and crack before the pond could be filled. With no water source on site, we needed to keep the clay moist until completion. To solve this, we covered the pond with damp hessian sheeting, which retained moisture and prevented further drying until rainfall replenished the site. This simple but effective measure preserved the integrity of the clay liner and ensured a watertight finish once the pond filled naturally.

The Results

The completed pond now provides a permanent, reliable water source for conservation grazing cattle and has already begun supporting amphibians, dragonflies, and wetland plants. The overflow system maintains a consistent water level, and the surrounding vegetation has regenerated quickly. The Wildlife Trust has since noted the positive impact on both grazing efficiency and biodiversity across the reserve.

Client Feedback

The Wildlife Trust team were extremely pleased with the outcome and commended the care taken to protect the sensitive bog habitat. They noted that the new pond blended seamlessly into the landscape and functioned well both ecologically and practically.

Lessons Learned

This project highlighted the importance of understanding soil and hydrology when working on bog and SSSI sites. By using low ground pressure equipment and adapting our approach to the site conditions, we achieved a durable and environmentally sensitive outcome. Our experience reinforced the need for flexibility when working with natural materials, particularly in challenging weather conditions.

Next Steps / Future Plans

Following the success of this project, we are exploring opportunities with the Wildlife Trust to deliver similar pond and wetland restoration projects on other reserves across Carmarthenshire and Pembrokeshire, building on the methods developed here.

Call to Action

We design and deliver practical, ecologically sound pond restoration projects across Wales. To discuss your next habitat enhancement project, contact Enviroculture to arrange a consultation.