Water quality and blue-green infrastructure in shallow urban groundwater: a case study in the Cape Flats, South Africa - Data Set
This is groundwater and stormwater quality and groundwater level data from a stormwater infiltration site in Mitchel's Plain, Cape Town, South Africa collected between June 2021 and August 2023. The study site, a stormwater detention pond owned by the City of Cape Town was retrofitted to enhance stormwater infiltration, as part of the project "Pathways to water resilient South African cities".
Paper Abstract
Cape Town, South Africa, is a water scarce city which is diversifying its water supply in line with its commitment to becoming a water sensitive city (WSC). Blue-green infrastructure (BGI) comprise multifunctional spaces which incorporate surface water and vegetation: the key infrastructure of a WSC. Over 200 stormwater detention ponds overlie the Cape Flats Aquifer (CFA) and offer potential to be transformed into BGI. The study site (a detention pond retrofitted with an infiltration swale and with vegetation that is allowed to grow without complete mowing) provides BGI at the stormwater-groundwater interface. This study investigated the impact of stormwater infiltration on the groundwater chemistry. Mean contaminant removal during infiltration ranged from 83% to 92% on a concentration basis after accounting for dilution effects. Furthermore, a significant decrease in the groundwater nitrate concentration was found below the BGI compared to background groundwater suggesting a net benefit for water quality.
Description of the data file
- The data consists of one file with three tabs.
- Water Chemistry Results: Column headers included the sample point, sample date and water quality parameters.
- Water Levels: Column headers include the data and the ID of each groundwater monitoring well.
- Sample Points: Column headers include a description of each of the sample points, coordinates of the monitoring wells, elevation of monitoring wells and depths of monitoring wells.
