Beyond Day Zero: Helping secure South Africa’s water supply

Day Zero. The day when Cape Town’s water supplies were expected to run dry. South Africa’s second-largest city has plenty of groundwater sources, but its population mainly relies on surface water, which can be impacted in times of natural emergencies.

That’s what happened in 2018 following a multi-year drought that severely depleted water levels in the city’s reservoirs. Although Cape Town avoided Day Zero through strict water savings measures, the city has not yet resolved the underlying problems in its water supply and is still at high risk of water shortages.

Denmark’s approach to mapping groundwater and providing clean water straight from the tap has proven inspirational to countries that use surface water for their water supply. That’s why South Africa recently began collaborating with Denmark on the Strategic Water Sector Cooperation programme to ensure access to safe and clean water.

Ramboll was recently hired as a consultant on the programme, tasked with demonstrating opportunities for use of groundwater as a water source to make South Africa less dependent on surface water.

“Extreme drought is likely to occur more frequently as greenhouse gas emissions from human activity continue to rise and warm our planet. South Africa and regions with similar climates need to put plans in place now to secure urban water supplies and avert scenarios like Day Zero system,” says Anker Lajer Højberg, Chief Consultant for Water Resources at Ramboll. “With decades-long experience of implementing the Danish Groundwater Mapping Programme, helping bring safe and clean drinking water to millions of people, Ramboll is well-placed to help improve water security and sustainability in South Africa,” he adds.

As part of the programme, Ramboll will work on the SAGMAA project that compares groundwater mapping and assessment in Denmark and South Africa to determine which Danish water solutions are transferrable to South Africa. The objective is to highlight opportunities for use of groundwater, and of Danish water technologies and approaches, in a South African context.

Ramboll will also implement a pilot project in the water scarce Saldanha Bay area north of Cape Town to establish a wellfield management system for the current water-supply structure that is based on surface water and groundwater. The project will, among others develop operational rules for use of ground and surface water; and develop software that integrates the operational rules to collect water data from multiple points both manually and in real time.

“The system is designed to allow for future extensions and conditions where managed aquifer recharge and desalination are expected to be included in the water mix. It could demonstrate how the Saldanha Bay area manages water resources in a secure and sustainable way,” says Anker Lajer Højberg.

• A wellfield is the area surrounding a permitted well from which potable water is pumped out.
• Managed aquifer recharge (MAR) is the intentional recharge of water to aquifers using natural water or treated waste and urban water for subsequent use or environmental benefit.
• SAGMAA (Development of a South African Groundwater Mapping and Assessment Approach) includes water resource experts from Ramboll, researchers from the University of the Free State in South Africa, and legal experts from the law firm ENSafrica.
• The Strategic Water Sector Cooperation programme is funded by Denmark’s Ministry of Foreign Affairs.