Between 1996 and 2005, natural catastrophic events had an estimated cost of US$575.2 billion world-wide. In particular, it has been observed that developing countries are relatively more affected by such events, since its gross domestic product (GDP) have showed sharper declines than developed countries' ratios. On August 15, 2007, an earthquake measuring 7.9 on the Richter scale shook the southern part of the central coast of Peru, with devastating consequences. Given the magnitude of the damage caused, one wonders how much less the cost of rehabilitating water and sanitation systems might have been if public investment projects and management of urban utilities (companies in charge of the water and sanitation provision), had incorporated disaster risk reduction measures. For this reason, and because this is a key public sector service for the wellbeing of population, the World Bank's water and sanitation program commissioned Apoyo Consultoria S.A.C. to conduct a research on the water and sanitation sector in order to attend the following inquiry: how much unpreparedness cost to the sector providing water and sanitation services? In other words, in economic terms, what will have been the gain to society or the reconstruction savings if risk prevention measures had been included in the management of services in the sector proposed for the analysis?

The hyper-arid conditions prevailing in Agua Verde aquifer in northern Chile make this system the most important water source for nearby towns and mining industries. Due to the growing demand for water in this region, recharge is investigated along with the impact of intense pumping activity in this aquifer. A conceptual model of the hydrogeological system is developed and implemented into a two-dimensional groundwater-flow numerical model. To assess the impact of climate change and groundwater extraction, several scenarios are simulated considering variations in both aquifer recharge and withdrawals. The estimated average groundwater lateral recharge from Precordillera (pre-mountain range) is about 4,482 m³/day. The scenarios that consider an increase of water withdrawal show a non-sustainable groundwater consumption leading to an over-exploitation of the resource, because the outflows surpasses inflows, causing storage depletion. The greater the depletion, the larger the impact of recharge reduction caused by the considered future climate change. This result indicates that the combined effects of such factors may have a severe impact on groundwater availability as found in other groundwater-dependent regions located in arid environments. Furthermore, the scenarios that consider a reduction of the extraction flow rate show that it may be possible to partially alleviate the damage already caused to the aquifer by the continuous extractions since 1974, and it can partially counteract climate change impacts on future groundwater availability caused by a decrease in precipitation (and so in recharge), if the desalination plant in Taltal increases its capacity.

The groundwater resources potential of Ethiopia is estimated to be about 40 billion cubic meters. Groundwater has been used as the main source of water supply since the 1970s for the main cities, towns and dispersed rural communities across the country, where provision of reticulated surface-water schemes is often expensive because of initial project construction costs and poor water quality. The exponential growth of the urban population and agriculture-led industrial development have resulted in greater attention to groundwater as the potentially cost-effective water supply source. As part of the growing focus on the use of groundwater, the Ethiopian government is currently implementing irrigation projects. One plan involves nine irrigation projects covering an estimated area of 8,000 ha, being developed on a pilot scale, with 9,000 test wells, 28,000 monitoring wells and 14,657 spring improvements. If this unprecedented Ethiopian groundwater-centred development plan is implemented successfully at such a scale, it is highly likely that its success will persuade other Sub-Saharan developing nations to put in place the necessary policies, regulations and investment for infrastructure and capacity development for exploring, exploiting and managing their groundwater resources.

Based on a five-town case-study cohort in Kenya, a conceptual framework has been developed to enable the formulation of holistic and effective strategies that encompass the national aspirations and regional to global sustainability agendas, and which can be used to monitor progress in achieving set objectives. The approach is flexible, scalable and transferrable, so that it can be applied in different contexts and using different indicators, based upon the same construct. Insufficient technical knowledge of urban aquifers and their interplay with the wider social-ecological system constrains the development of holistic, effective and robust management systems to ensure their sustainability for intended uses. The objective was to consider governance and management solutions that could promote water security for urban towns in Kenya through the sustainable use of groundwater in the context of its complex hydrogeology, water access disparities, competing uses and future risks. The in force national and county water policies, strategies, and plans for the case study areas were critically reviewed. The status of aquifer knowledge, water access disparities, competing uses, and risks was evaluated from critical literature reviews and data compilation, fieldwork, and analysis of indicator datasets from the Kenya 2009 census. Key aquifers need urgent characterisation to reverse the current situation whereby development proceeds with insufficient aquifer knowledge. Private sector and public participation in management should be enhanced through decentralised management approaches. Water infrastructure and technologies should be fit-for-purpose in application and scale, and the pro-poor focus should be underpinned by appropriately focused management regimes.