Catchment Significant Pressures and Issues Description: The significant issues identified for the Lingaun_010 were phosphate and sediment with forestry identified as a significant pressure for the third cycle.
This waterbody deteriorated to moderate status in 2013-2018. EPA biological assessment at the monitoring point in 2020 recorded a Q Value of 3-4* (* siltation impact). As the waterbody has a high status objective, it is very sensitive to low levels of inputs, and therefore all risks to water quality will be referred where identified.
This protect referral is being issued to highlight issues around felling that may be needed in future to minimise risk of sediment loss to the river.
Referral Significant Issue (s) Description
SSIS was undertaken at EPA operational station: Br u/s Whitehall Br (RS16L010050) in July 2023. The site was found to be Probably not Significantly Impacted with a score of 8. However, tolerant taxa were present in excessive numbers and the site was not considered to be meeting high status requirements. Moderate to high levels of interstitial sediment were also noted. Chemistry sampling in August 2023 and January 2024 did not show any exceedances of the EQS thresholds.
A catchment walk was undertaken in August 2023 in the clearfelled area 2 km upstream from Br u/s Whitehall Br. It was found that buffers had been maintained in some areas but absent in other areas with clearfelling occurring right up to the river bank. In-drain sediment screens were in use in the clearfelled area but some were operating more effectively than others. Some were found to have disintegrated while others were likely to be bypassed in high flow situations. One sediment screen had been erected in a tributary of the waterbody.
While LCA undertaken within this waterbody demonstrates impact and biology not considered to meet certain high status criteria, it is important to mention that this forestry protect referral relates to observations on the ground showing enhanced risk from the failure of sediment screens in forestry drains and clear felling on the river bank.
Recommendation: protection measures will be required around future clearfelling to ensure that silt trapping measures are effective (ensure proper maintenance during and after clearfelling activities). There is also a need to establish proper setbacks (restructuring of the forest) for future planting activities. It is important to highlight the high status objective and therefore high sensitivity of this waterbody within future clearfelling applications.