RAND WATER ANNUAL REPORT 2023

Project Name

Groundwater Exploration Using Digitally Enhanced Technologies

Objectives

• To illustrate the capabilities of modern digital technology to rapidly scan large tracts of land and determine high-confidence groundwater reserves. • To confirm and compare groundwater exploration and groundwater digitally enhanced technology with traditional methods to establish its viability as a business case study for applications in Rand Water operations towards achieving its other strategic objectives. • Successfully piloted the use of hyperspectral satellite technology and image analysis to identify groundwater aquifers. Nano-spectra remote sensing employs sensors, fixed on satellites, which measured the radiation emitted off the Earth’s surface. Nano-spectra raw measurements were de-convolved into > 200 discrete wavelength bands within each pixel or instantaneous field of view. • The area investigated using digital technology exhibited nano-spectra responses consistent with the presence of potable water. The drilling and pumping tests resulted in good flow rates that can be exploited in future.

Results

Value created

• The geophysical investigation demonstrated the detection capability of the two (2) methods.

• The fast EM method where data can be acquired at a slow walking speed is preferred compared to the much slower seismic refraction method.

Project Name

Monitoring of Cyanobacteria Blooms in the Vaal Dam using Satellite Remote Sensing

Objectives

• To perform a high-level investigation into the application value of satellite imaging in Rand Water based on a trial period as supported by the Water Research Commission. • To determine correlations between real-time satellite images and results generated from in situ samples and analyses based on an additional 6-month in-depth investigation. • To determine the usefulness of the satellite imaging service in monitoring water quality and possible integration into the Rand Water ‘Water Quality Monitoring Programme. • The Cyanolakes website can be accessed continuously for results from the Sentinel 2 satellite monitoring cyanobacteria and chlorophyll-a in the Vaal Dam. These results provide the satellite imaging on average for the whole dam. From these results, the increasing and decreasing trends can easily be detected by satellite imaging and modelled results.

Results

Value created

• Reduce the consumption of disinfection chemicals.

•

Reduced cost of chemicals growth.

142