Leaky dams

"Leaky dams" helping reduce flood risk in Harrop Brook and River Dean

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"Leaky dams" at Pott Shrigley in Cheshire have been working well during Storm Barra over the past couple of days, helping to slow down the flow of flood water in Harrop Brook and the River Dean. 

Leaky by name, leaky by nature, even during high flows, "leaky dams" are built in small streams from natural materials - they will only let a certain amount of water through, slowly draining the trapped water to reduce the flood peak.  They are part of Natural Flood Management measures being implemented by a range of public sector and third sector organisations across the Mersey catchment to help reduce flood risk.

Funded by the Environment Agency, Mersey Rivers Trust installed the leaky dams at Pott Shrigley in March 2021, working in partnership with local farmers and landowners. Monitoring by Mersey Rivers Trust staff today (9 December) has shown that these new leaky dams have been able to hold back water in the headwaters of Harrop Brook and slowing down the flow of water into the downstream River Dean. 

Over the coming months, Mersey Rivers Trust will also be planting new trees at Pott Shrigley to complement the leaky dams.  Once established, the new trees will help take up water and allow more water to soak into the ground during flood conditions, further slowing the flow of water into the downstream river system.

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