Geohydrological Monitoring and Assessment (GMA)

Groundwater Resource Assessment Phase II (GRA II) is a model for estimation of groundwater allocation scenarios. It provides an introduction to the world of groundwater quantification on local and regional levels.

GRA II is designed to model a distinct geohydrological or hydro-lithological unit (such as a groundwater flow basin) and to provide a rough, desk-top estimate of the status of the groundwater resource and what volume might be abstracted without damaging local surface aquatic ecosystems over the long-term.

Dimensional (area, X and Y dimension, grid-resolution), geohydrological (aquifer thickness, saturated thickness, hydraulic conductivity, etc.) and recharge data are required as inputs. 2-dimensional grid representations of the area are produced. A series of algorithms quantifies the groundwater potential. This methodology may generate water balance data for each cell, including for any surface-water course cells that can then be compared to surface flow data.

National Groundwater Quality Monitoring Programme

The National Groundwater Quality Monitoring Programme ascertains the influence of rainfall on the groundwater quality and determines the groundwater quality. It also provides information about the Groundwater Quality Monitoring Network, basic information about monitoring parameters and preliminary results.

The spatial distribution of groundwater quality monitoring Geosites and their data is also available.

Current Research & Development Projects and Programmes

• Projects and Programmes - not updated

Water Use License Assessment (WULA)

Sub-Directorate: GRAM is responsible for assessment of water use allocations as regulated under National Water Act (Act 36 of 1998). The assessment also includes the evaluation of any groundwater monitoring network that is required to support management of the resource from which the water is to be abstracted. All the available groundwater assessment information (regulation by current General Authorisations, Harvest Potential data, Exploitation Potential [C Haupt, 2003] information, Groundwater Reserve Determinations per Quaternary Catchment, WARMS data and GRA II information) is applied to perform a local water balance model for each water use license assessment. Future optimisation of this application will use supporting software like GRDM (Groundwater Resource Directed Measures, version 3.1).

>> Related information

• Requirements for Water Use License Application - Groundwater Abstraction [PDF - 158 KB]
• Assessment Tool for Water Use License Assessment - Groundwater Abstraction [PDF - 129 KB]
• Integrated Water Use License Application – Draft Assessment Questionnaire [PDF - 64 KB]

Photo Gallery

• An artesian borehole near Oudtshoorn overflowing at 26 litres per second
• The hydrogeochemical sampling unit servicing the rainfall monitoring station
• Drilling site at Nossob River on South African side, close to Nossob Camp - hazardous drilling circumstances.
• Geosite Logger Housing at Far West Rand
• South African Groundwater Ecological Support
• Irrigation from groundwater
• Rainfall logger – Bulk Sampler
• Groundwater strike event
• Surface water, Rainfall, Groundwater Monitoring site
• Field Water Quality Measuring Instruments (photometric for determination of dissolved solids in groundwater)
• Flow cell with field water quality instruments (Electrical Conductivity (EC), Temperature (T), pH, Dissolved Oxygen Content (DOC)). Water inflow cell comes directly from borehole through pumping system
• The hydrogeochemical sampling unit servicing the groundwater monitoring station
• Flow cell to stabilise the turbulence in water line while measuring Dissolved Oxygen in groundwater
• Close-up of flow cell
• Flow cell with Dissolved Oxygen meter
• Piezometers at the Cape West Coast

For details on our research and development contact Mr. Ramusiya Fhedzisani.