For this project, along the River Test and its tributary the River Dun, habitat enhancements were made, and angler accessibility was improved. This channel enhancement project was carried out as part of the Flow Resilient Sustainable Habitat (FReSH) Water Programme.
Migrating salmon have been observed in the River Test despite spawning habitat being limited. The remnants of a historic rock weir were removed, which improved flow speed and reinstated natural sediment transport, improving the quality of the existing spawning habitat. Upstream of the weir, localised, in-channel redistribution of sediment build-up was carried out, creating variation in the water flow. To provide additional salmonid spawning habitat, and improve conditions for favourable chalk stream aquatic plants, three gravel riffles were installed using locally sourced angler gravel.
A series of seven brushwood berms were installed on the River Test, and three on the River Dun, to improve marginal habitat, locally narrow the channel, and improve flow diversity. Since their installation, silt that has been deposited within the structure has helped the marginal plants to establish and cover over the berm almost completely.
On the River Dun, three angler-accessible berms were built using onsite hardcore material. These berms are solid underfoot and continue seamlessly from the existing bank. Like the woody berms, the angler berms locally narrow the channel and therefore increase the flow speed of the river.
The River Test carrier stream was densely wooded, and therefore heavily shaded, on the true left-hand bank, limiting the growth of favourable chalk stream macrophytes. To allow more light onto the river channel, coppicing, pollarding, and felling of selected trees and tree limbs was carried out.
The completion of this project has successfully allowed for marginal habitat creation, salmonid spawning habitat improvement, the reinstatement of natural sediment transport, and improved angler access.
