DIG-ging Deeper: Soil selection drives hydraulic performance in highway rain gardens

This repository contains the datasets supporting the study “DIG-ging Deeper: Soil selection drives hydraulic performance in highway rain gardens”. The data describe the performance of four instrumented highway rain gardens installed in Broadway, Grimsby, UK, as part of the Doncaster, Immingham and Grimsby Surface Water Resilience Project. Each rain garden used the same hybrid attenuation crate design but contained a different soil medium: recycled local soil, standard engineered Soil A, standard engineered Soil B, or a premium engineered soil mix. The repository includes monitoring data from the 2024 to 2025 hydrological year, covering rainfall, soil moisture, outfall water depth and electrical conductivity. Soil moisture was recorded using vertical and lateral Sentek TriSCAN probes, while outfall chambers were monitored using CTD probes. These data allow comparison of vertical infiltration, lateral wetting, runoff attenuation, outfall response and indicative solute transport between soil types under operational highway runoff conditions. The dataset also supports comparison between rain garden soil behaviour and natural soil conditions at the nearby monitoring site. It is intended to enable transparent reuse of the data, support independent analysis of rain garden performance, and contribute to the evidence base for soil selection in sustainable drainage systems and nature based solutions.