Liza Beck is a very erosive and fast-flowing lakeland stream. A significant barrier ( a weir with 0.8m of hanging water) is formed by the concrete cap over the drinking water main from Cornhow Water Treatment Works. In partnership with both the Rivers Trust & United Utilities (water company) the eel pas and fish easement were constructed. In the autumn, following construction, two pairs of salmon were found spawning up-stream the obstruction.