Provision for Cornmill Meadows Hydrological Study

Lee Valley Regional Park Authority invites tenders for an in-depth Hydrological Study at Cornmill Meadows, Waltham Abbey, EN9 2ES. Cornmill Stream and Old River Lea SSSI is designated for its outstanding assemblage of dragonflies and damselflies. A high-level survey of the site in 2022 found that these species are under threat due to falling water levels and highlighted the urgency of an in-depth hydrology survey to assess the causes and plan for remediation. In addition, work currently underway at the neighbouring Royal Gunpowder Mills (RGM) site seeks to address issues with the co-located Waltham Abbey SSSI. The next stage of that project requires monitoring of water flows in the Cornmill Stream and Old River Lea. The results of this study should meet that demand. Our aim is to understand the hydrology of the Cornmill Stream and Old River Lea SSSI, with particular reference to water flows through the site, and to inform future water management requirements, including under extreme conditions which may occur due to climate change.