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The paper presents an improved approach for investigating submarine groundwater discharge (SGD) based on radon mapping and radon mass balancing in the coastal sea. While the use of radon as an environmental tracer in SGD studies is well-established, we identified based on our longstanding experience six methodical shortcomings of the conventional approach and suggest corresponding developments. The shortcomings include: (1 and 2) inadequate consideration of both detection equipment response delay and influence of tidal stage; (3 and 4) incorrect quantification of radon losses, due to offshore mixing and degassing resulting in a potentially incorrect radon mass balance; (5) inaccurate determination of the terrestrial groundwater endmember, due to inhomogeneous radon distribution in the coastal aquifer; and (6) difficulties in distinguishing between discharged fresh groundwater and recirculated seawater. The improved approach is practically demonstrated in a step by step manner in a large-scale field study, which was carried out in False Bay (South Africa) and which consisted of two parts, namely (i) qualitative SGD localization along the entire False Bay coastline based on coastal radon distribution patterns and (ii) quantitative SGD investigation within a defined coastal area of interest (AOI) based on a radon mass balance (RMB). The plausibility of the AOI related results was evaluated by a hydrogeological model, used for qualitative SGD localization, and a hydrological model, applied for estimating groundwater recharge within the AOI catchment.

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Groundwater is not being perceived as an important water resource and therefore has been given limited attention in South Africa. This is reflected in general statistics showing that only 13% of the nation's total water supply originates from groundwater. In contrast, most towns in arid areas depend on groundwater either as a sole supply or as an essential supply for drought management. The perception remains that groundwater is not a sustainable resource for bulk domestic supply and cannot be managed properly. Despite this, a growing number of municipalities utilise groundwater on a regular basis, and provide examples of successful management of this resource. Various guidelines for groundwater management in South Africa have been developed. These are valuable sources of information in terms of requirements and steps to protect and manage aquifers. However, an overarching groundwater management framework was still lacking. Hence, the Water Research Commission (WRC) has commissioned a project to develop a Groundwater Management Framework that incorporates all aspects of groundwater management at municipal level. The proposed Groundwater Management Framework aims to improve on the management of groundwater resources by equipping the responsible authorities with the required tools and capacity. This goes beyond data collection and monitoring, and requires human and capital resources. The framework includes a detailed description of the different functions and the relevant responsibilities, the required skills, the optimal position within the municipal structure and required communication lines. Hence, the assigned responsibilities and available tools to achieve sustainable groundwater management reflect the local level of water institutions, i.e. Water Services Authority (WSA), Water Services Provider (WSP) and Water User Associations (WUAs). However, the principles of the framework can be applied at all levels and all scales. It is recommended that this framework be rolled out and promoted at the local government level, in combination with requisite skills development at operational level, and training of municipal officials, as well as providing incentives for successful implementation and integration of groundwater management in municipal planning.

The Department of Water Affairs (DWA) has embarked on a nationwide programme to develop water-reconciliation strategies for all towns across the country. Reconciliation strategies for the major metropolitan areas and systems (e.g. Johannesburg/Pretoria, East London, Cape Town and Durban) were developed next. The implementation of these strategies is monitored by strategy steering committees. The approach has now been extended to all other metropolitan areas as well as all towns and villages or clusters of villages. In order to prepare the actual strategies, regardless of the size of the town, thorough documentation, research and analysis of the available information was required, as well as evaluation of projected growth scenarios to assess water requirements over the next 25 years and identification of potential additional sources to meet this growing requirement. It has emerged that the poor operation and maintenance of water supply, treatment and reticulation infrastructure are resulting in significant losses, which, if corrected, can reverse the current water shortages being experienced. Similarly, the generally poor management of effluent remains a threat to surface water and groundwater quality downstream. It appears that many municipalities perceive groundwater as an unreliable resource; however, in general, the issue of staff and skills shortages to manage the resource effectively is the actual problem. This is an operational issue rather than a groundwater-resource-specific issue. This aspect requires special attention for existing groundwater schemes and proposed groundwater development. In most instances water conservation and water-demand management and the development of local surface and groundwater resources are the most feasible options to meet any current or projected future water-supply shortfalls. Any intervention must be combined with a skills-development programme at the operational level to ensure the sustainability of the proposed supply options. This paper is based on the experience gained in the development of reconciliation strategies for the towns and villages in the DWA Southern Planning Region (i.e. surface water drainage areas in the Eastern Cape and Western Cape Provinces), which was carried out by Umvoto Africa in association with engineering consulting practice Aurecon.Keywords: water supply, water reconciliation, groundwater options, operation and maintenance, water conservation and water demand management All towns reconciliation strategies studyIn 2008 the Department of Water Affairs (DWA) commenced with a nationwide programme to develop water reconciliation strategies for all towns, villages and clusters of villages across the country, following on the good progress with the reconciliation strategies for the metropolitan areas. The overall objective of the studies was to provide first-order water availability and water requirement reconciliation strategies for all towns and villages in South Africa (DWA, 2009b). The large numbers of rural villages that occur in the ea...