City of Cape Town, Western Cape Province, South Africa – Operating groundwater augmentation using stormwater and recycled water
Atlantis is located 50 km north of the City of Cape Town along the semi-arid west coast of South Africa, with a population of over 76,000 people.
Water scheme overview and configuration
The Atlantis Managed Aquifer Recharge scheme was initially developed in the 1970s by the National Department of Water and Sanitation to supply water to the satellite hub of Atlantis, Pella and Mamre. Although it is a single aquifer, the Atlantis Scheme has two distinct nodes, the Witzands and Silwerstroom nodes.
The Managed Aquifer Recharge component includes the infiltration of both conditioned stormwater and treated recycled water into strategic zones of the aquifer, to ensure sustainability of the aquifer biome over the long term. The scheme is currently permitted for 13 million litres (3.4 million gallons) per day.
Under normal operating circumstances, all higher quality treated effluent from the domestic stream at the Westfleur Wastewater Treatment Works is used to recharge the aquifer. The lower quality treated effluent from the industrial stream at the Westfleur Wastewater Treatment Works is directed to the infiltration ponds situated closer to the coastline. Similarly, stormwater is selectively directed to the aquifer recharge ponds and the coastal infiltration ponds.
There is a project underway to revitalise the aging scheme, and to expand the capacity and capability of the Wellfield to 35 million litres (9.2 million gallons) per day. The wellfield supplies water to the municipal supply system, for customers.
The Atlantis Supply system will also be expanded to include areas that are traditionally supplied from the Voelvlei Water Treatment works during drought.
Atlantis aquifer under the Cape Town Water Strategy
The Atlantis Aquifer Scheme New Water Project comprises the following initiatives:
Revitalisation / renewal – adds 10 million litres (2.6 million gallons) per day)
- Upgrade of the Witsands and Silwerstroom Wellfields
- Upgrade of the Witsands Water Treatment Works
- Upgrade of the Silwerstroom Water Treatment Works and Supply System
- Upgrade of the stormwater recharge system
Expansion – adds 10 million litres (2.6 million gallons per day)
- Development of new wellfield
- Development of new treatment plant
Resources