Environment Agency: Hydroecology Modelling Tool (HEM) development to inform environmental assessment in water company drought planning.

Tender description

Water companies are required to monitor, assess and, where possible, mitigate for the environmental impact of their supply side drought management actions. This includes setting out environmental assessment, monitoring plans and mitigation measures as part of the drought planning process. However, in our role as statutory consultee and advisor to Government on water company drought plans (WCDPs) we have identified that completing environmental assessment to understand the impact of supply side drought management actions (including drought permits/orders) is a significant challenge for many water companies. Some of the key challenges include: limited time series of baseline environmental datasets to enable understanding of the environment under 'non-drought' and previous drought conditions; assessing the sensitivity of the environment to flow changes due to supply side drought management actions; predicting the likely effect on the environment of flow changes due to supply side drought management actions; ascribing a level of confidence/certainty. Developing improved hydroecological modelling tools is essential in helping water companies to address these challenges and thus improve environmental assessment in the drought planning process. This project will develop/refine an existing Environment Agency prototype tool (DRIED-UP - written in R code with a shiny app user interface) into a Hydroecological Modelling (HEM) tool for water companies to use to inform their environmental assessments in the next round of statutory drought plans. The key functionality that will be developed as part of this project is: 1) quantifying ecological (macro-invertebrate) sensitivity to flow alteration (due to supply side drought management actions); 2) understand uncertainty associated with the environmental assessment/modelling results; 3) allow predictions of ecological (macro-invertebrate) response to alternative flow alteration scenarios due to implementation of different supply side drought management actions. We expect that the development/refinement of this tool through this project will result in an improved functionality and usability through development of options/features and improved graphical displays. Delivery of this hydroecological modelling tool will help water companies improve their environmental assessments whilst also having the potential to allow them to use their results to better inform choices around their drought management options.