Groundwater is a strategic water resource in rural Limpopo and accounts for almost 70% of rural domestic water supply. Groundwater is available throughout the province, but in varying quantities and qualities depending upon the hydrogeological characteristics of the underlying aquifer. Surface water resources contributes largely to the urban and industrial supplies and in many areas of the Province it is fully utilized, further to this it is difficult to economically develop surface water in rural areas often developed as dispersive clusters of villages over large areas associated with poor infrastructure and challenging geographical conditions. As a result groundwater is fast becoming the only option left for further development of bulk water resources.
As a result of the intrinsic low primary permeability and porosity of the underlying geology it is not an easy task to develop bulk groundwater resources. The occurrence of groundwater is related to secondary hydrogeological properties developed from the process of weathering, faulting, fracturing and the influence of intrusive units. As a result the drilling of successful water supply boreholes will always be a challenge and needs a scientific approach. Within the Province this is often not the rule, with Water Service Authorities developing new boreholes randomly with limited scientific input, ranging from not enough geophysical support to not testing boreholes correctly. In most cases no attention is given to existing borehole information or the Limpopo GRIP dataset consisting of over 4000 constant pumping tests and over 7000 recommended abstraction rates, while 5900 are recommended for a 24 hr duty cycle. Information derived from the Groundwater Resource Information Project (GRIP) indicates that an estimated 576 000 m3/day (210 Mm3/annum) have been recommended for abstraction from boreholes in approximately 2500 villages situated all over the Province. However, less than half of these boreholes are equipped. As a result more than 3000 boreholes are unequipped with a combined recommended abstraction rate based on a 24 hr duty cycle of 109 Mm3/a.
Poor drilling results, poor water quality and the common failure of boreholes have led to the perception amongst water users that groundwater resources are not an option as a bulk water resource. Adding to this is the fact that effective groundwater management within in South Africa is not yet fully understood. Rural communities with no other sources of water view abstraction from boreholes as a substandard resource suited for poor communities which cannot afford piped surface water. As a result groundwater resources are underutilised and underdeveloped and it remains difficult to successfully develop groundwater as a bulk water resource.
Glen Alpine Regional Water Scheme
There was a water shortage in the Glen Alpine area. The project was on the table to raise the level of the dam at high cost to the government and the local community. The water was not even chemically class zero water (class zero is required for drinking water). If the dam was raised there would have had to be a purification plant built as well. This would have added substantial cost to an already expensive project.
Groundwater was considered, but the available data at that time was inconclusive at best and negative at worst. A group of consultants, many of which are now part of the GRIP initiative, embarked on a complete survey of groundwater in the area. These GRIP consultants wanted to prove that groundwater was a good, clean and much cheaper option than surface water.
Based on the conclusion of their group effort and survey data the very expensive damn extension project was scrapped and the groundwater option was implemented.
Because of the Glen Alpine project, the consultants realised they had to share data constantly. The GRIP initiative was born.
Middle Letaba dam
If the GRIP data were available during during the drought of 1992 to 1996, 70% of the water crisis could have been solved without having to spend any money. Because the GRIP database was not available engineers had to be sent far and wide at great expense to check the water situation and find alternative ground water sources to supplement surface water sources.