City to city learning and knowledge exchange for climate resilience in southern Africa

responsible for energy supply and regulation of rates in Harare and Zimbabwe from the main grid. South Africa is ranked 114th out of 115 nations in its readiness for an energy transition away from fossil fuels [70], and yet addressing climate issues and associated problems in the region is closely related to tackling southern Africa’s dependence on coal. Climate change poses a looming power threat to hydropower, with changing rainfall, temperature and evapo- ration in watersheds such as the Zambezi (where countries such as Zimbabwe, Zambia and other southern African countries and subsequent cities draw hydropower from) have potential impacts on hydropower production. Power rationing programs have been implemented across the region, including in South African and Zimbabwean cities. Lusaka and Harare have a com- mon energy production and supply resource having a 45:55% power sharing between Zambia and Zimbabwe respectively from Kariba hydropower stations that are along the Zambezi River, but Zambia also draws hydropower along the Kafue River. Water governance. The CoW provides an admirable example of how partnerships—in this case, a public-private-partnership (PPP) has worked in favour of the city. Windhoek is the only city among the four, which reclaims domestic wastewater to potable drinking water stan- dards at the Goreangab Water Reclamation plant, which was one of the sites visited under the city exchanges. The reclamation process began operations in 1968, when the plant was built by the CoW to reclaim waste directly from domestic sewage effluent [71]. The new Goreangab

Water Reclamation plant was built in 2002 and has been based on extensive experience, local research, and input from international experts to assure compliance to the strictest water qual- ity guidelines applied internationally [72]. The Resilience City Planning Framework (RCPF) is a complex phenomenon, non-deterministic, dynamic in structure, and uncertain in nature [73]. This context poses new opportunities for collaboration among public, private, civil insti- tutions and organizations on all levels. In addition, artificial recharge of aquifers implemented in the CoW provides another important lesson in groundwater abstraction and water management. The city supplies groundwater abstracted from municipal production boreholes, which is different from Harare, where water management is under the control of public entities, and water treatment and sup- ply is the sole mandate of the city council. In Lusaka on the other hand, water is managed by a commercial utility, which is a private company wholly owned by the local authority [74]. Sur- face and groundwater resources in Harare and Lusaka are dwindling due to increase in demand and unregulated abstraction. In Harare, drilling a borehole requires a permit from the country’s raw water regulators, the Zimbabwe National Water Authority (ZINWA) but they are poor regulators and enforcers of this piece of legislation. As such individuals across Harare have drilled boreholes in their residences, in a similar way to Lusaka. In Lusaka, borehole dril- ling has only recently been regulated by the Water Resources Management Agency

(WARMA), which issues permits for abstraction. The Water Resources Management Act Number 21 of 2011 requires all borehole owners to register their boreholes at a fee. This is being done in order to take stock of the number of boreholes and to monitor the abstraction levels of groundwater, which is at risk of contamination and depletion in Lusaka. In contrast, in Windhoek, permission for borehole abstraction is granted by the Ministry of Agriculture, Water and Forestry (MAWF), and the city has created an efficient groundwater abstraction and recharge system where water can be artificially recharged into city aquifers for storage pur- poses, since the evaporation rates are very high. The same water is treated to potable water standards before it is pumped into permissible boreholes in a scheme known as the Windhoek Managed Aquifer Recharge Scheme, providing a centralized borehole system which is easier to monitor and maintain; which again provides a good case of water management that other cit- ies can learn from. City learning in southern Africa PLOS ONE | https://doi.org/10.1371/journal.pone.0227915 January 24, 2020 15 / 25