3.1 The Need for Artificial Recharge – Setting the Scene
The town of Atlantis is approximately 50 km north of the City of Cape Town, South Africa, forming part of the Cape Town metropolitan area. Atlantis experiences a Mediterranean climate with most of its 450 mm mean annual rainfall occurring in winter, between April and September. Up to 30 percent of the rainfall recharges the underlying groundwater system, particularly through unvegetated dune areas. The town was established as an industrial town, based on the “new town concept”, being far enough from the center of Cape Town to be self-contained, where everyone living would be employed in the town, Tredoux and Cave (2002). A summary of the Atlantis water supply is provided in Table 2.
Table 2 – Atlantis Water Supply Scheme.
Name of scheme | Atlantis Water Supply Scheme |
Location | Atlantis Aquifer, Cape Town, South Africa |
Mean annual rainfall | 450 mm/year |
Source of water | Storm water and secondary treated wastewater |
Type of aquifer | Primary aquifer, predominantly sand, some calcrete and peat |
End use of water | Industrial and domestic use |
Type of managed aquifer recharge | Large infiltration basins |
Current average volume of water recharged | 7500 m3/d storm water and treated waste water |
Volume of water recovered | 2.7 Mm3/year |
Year commenced | 1979 |
Owner/management of scheme | City of Cape Town |
Unique attributes of this MAR scheme | Water re-use, both wastewater and stormwater, good example of integrated water resource management |
The initial groundwater supply planned for Atlantis was insufficient to support the population and growing industry within the area, Tredoux (1987). The closest alternative water source was the Berg River, which is 70 km away and piping water to Atlantis would be too costly, Tredoux and Cave (2002). Thus, groundwater resources were further explored and the Witzand and Silwerstroom wellfields were developed (Figure 8). Stormwater detention basins were constructed and much of the water infiltrated into the sandy soils, inadvertently recharging the groundwater.
The shift to intentionally, artificially recharging the aquifer came as a result of a change in national legislation, which introduced a strict permitting system for wastewater discharge and a stringent monitoring protocol. Until the 1970s, marine discharge of treated wastewater was common practice in South Africa. The costs associated with adhering to the new pollution control measures became prohibitive for Atlantis. Based on the results of successful pilot studies in Cape Flats (1973-1979) to investigate alternative applications of wastewater, recharging the local aquifer with treated wastewater was initiated in Atlantis in 1979 (DWAF, 2010; Quayle, 2012). Figure 8 shows the town, industrial area, and all the major components of the water management system.

Figure 8 – Town of Atlantis along the west coast of South Africa (Bugan et al., 2016).