Munir A. Hanjra’s research while affiliated with Africa Institute of South Africa and other places

Throughout history, the first and foremost role of urban water management has been the protection of human health and the local aquatic environment. To this end, the practice of (waste-)water treatment has maintained a central focus on the removal of pollutants through dissipative pathways. Approaches like – in the case of wastewater treatment – the activated sludge process, which makes ‘hazardous things’ disappear, have benefitted our society tremendously by safeguarding human and environmental health. While conventional (waste-)water treatment is regarded as one of the greatest engineering achievements of the 20th century, these dissipative approaches will not suffice in the 21st century as we enter the era of the circular economy. A key challenge for the future of urban water management is the need to re-envision the role of water infrastructure, still holding paramount the safeguard of human and environmental health while also becoming a more proactive force for sustainable development through the recovery of resources embedded in urban water. This book aims (i) to explain the basic principles governing resource recovery from water (how much is there, really); (ii) to provide a comprehensive overview and critical assessment of the established and emerging technologies for resource recovery from water; and (iii) to put resource recovery from water in a legal, economic (including the economy of scale of recovered products), social (consumer's point of view), and environmental sustainability framework. This book serves as a powerful teaching tool at the graduate entry master level with an aim to help develop the next generation of engineers and experts and is also highly relevant for seasoned water professionals and practicing engineers. ISBN: 9781789060317 (Paperback) ISBN: 9781780409566 (eBook)

Investments in irrigation contribute to poverty reduction and enhance food security. This paper considers irrigation investments more broadly in the context of rural–urban linkages and thus examines rural irrigation schemes and peri-urban and urban agriculture using freshwater, groundwater and wastewater. We present case studies from East, West and Southern Africa, while focusing on the imperative of smallholders and of food security and nutrition. Evidence from Big Data and telecoupling show that, amid global change and sustainability issues, irrigation development strengthens connections between humans and nature with notable benefits to food security. Transforming investments to feed the future generation require priority investments in irrigation, solar energy for groundwater pumping, groundwater development policy, and integration of peri-urban and urban agriculture into food systems. Equally important will be no-regret interventions in wastewater reuse, water storage and groundwater buffer, micro-irrigation, and wholesale reconfiguration of farming systems, through anticipatory investments, to safeguard food security and sustainability into the distant future.

Investments in agricultural technologies, capacity building and policy harmonization are needed to support sustainable development across Africa. Regional development projects can facilitate the adoption of agricultural technologies and innovations across nation‐state borders and generate benefits for shared prosperity. This paper uses panel data from 1,160 smallholder households including beneficiaries and non‐beneficiaries from five countries in East Africa ‐ Burundi, Kenya, Rwanda, Tanzania, and Uganda. From a pool of over 90 projects implemented over a span of 15 years, 23 regional projects are included in this study. The major economic benefits to smallholder participants are higher crop productivity and income, access to adaptable technologies, access to markets, higher livestock and milk production, gender equality, enhanced food security, resilience and capacity building for uptake and scaling up of future innovation platforms. For example, the adoption of low‐cost tissue culture banana by the beneficiaries increased their incomes by 15% in Rwanda while the adoption of appropriate land and water management technologies increased the potato yields from 2.8 tons (USD 2,840/ha) to over 7.5 tons (USD 7,410/ha) in Kenya. The beneficiaries ensured value added to commodities like bananas (for export) and orange‐fleshed sweet potatoes (a nutrition‐sensitive intervention for enhancing domestic intake of vitamin A) in Burundi, Kenya, Rwanda and Uganda. Additionally, milk production increased from 6 to 11 L per cow per day in Uganda and from 6 to 8 L per cow per day in Tanzania, with increases in sales generating USD 115 per cow per month above the non‐beneficiaries. These results are supported by previous studies on technology adoption, investments in agriculture and well‐being outcomes. Our findings with the higher farm income Difference‐in‐Differences (DiD) estimator for the female beneficiaries compared to male beneficiaries might have important implications for investing in regional development projects that will close the gender gap in agricultural productivity in Africa. Regional projects can also support post‐conflict development efforts for food security and peace in fragile contexts such as in Burundi. Our findings might serve as an input to the African Union's Comprehensive Africa Agriculture Development Programme, localization of the United Nations Sustainable Development Goals related to food security and agriculture in Africa and an input to monitoring, evaluation and learning.

In low- and middle-income countries, the management of fecal sludge from on-site sanitation systems has received little attention over many decades, resulting in insufficient or missing regulations to guide investments and management options. To address this gap, this report examines existing and emerging guidelines and regulations for fecal sludge management (FSM) along the sanitation service chain (user interface, containment, emptying, transport, treatment, valorization, reuse or disposal). It also draws empirical examples from guidelines across the globe to support policy-makers, planners, and sanitation and health officers, as well as consultants in low- and middle-income countries in the development and design of local and national FSM guidelines and regulations.

The study examines possible water savings by replacing alfalfa with winter wheat in the Fergana Valley, located upstream of the Syrdarya River in Central Asia. Agricultural reforms since the 1990s have promoted this change in cropping patterns in the Central Asian states to enhance food security and social benefits. The water use of alfalfa, winter wheat/fallow, and winter wheat/green gram (double cropping) systems is compared for high-deficit, low-deficit, and full irrigation scenarios using hydrological modeling with the HYDRUS-1D software package. Modeling results indicate that replacing alfalfa with winter wheat in the Fergana Valley released significant water resources, mainly by reducing productive crop transpiration when abandoning alfalfa in favor of alternative cropping systems. However, the winter wheat/fallow cropping system caused high evaporation losses from fallow land after harvesting of winter wheat. Double cropping (i.e., the cultivation of green gram as a short duration summer crop after winter wheat harvesting) reduced evaporation losses, enhanced crop output and hence food security, while generating water savings that make more water available for other productive uses. Beyond water savings, this paper also discusses the economic and social gains that double cropping produces for the public within a broader developmental context.

Underground taming of floods for irrigation (UTFI) is a new approach for mitigating flood impacts through targeted floodwater storage in depleted aquifers for irrigating crops in the dry season. UTFI not only fosters the much desired conjunctive use and management of water resources but also provides the environmental services that are of high socioeconomic value. UTFI interventions are individually established at the local scale (e.g. village pond, check dam) but to achieve more substantial positive benefits at the scale of meso watersheds (10 s of km2) or sub-basins (100–1,000 s of km2) in the flood-prone river basins requires area-based implementation. Given the nature and scale required, UTFI needs to be managed at the community level with the help of appropriate insti- tutional arrangements taking into account both the upstream and downstream locations. This paper reviews the existing institutional approaches and proposes an institutional framework that can help to mainstream UTFI man- agement in the context of South Asia. The proposed model is centred on the existing formal institutions and also integrates non-market (participatory) and market (payment for ecosystem services) instruments that can provide win–win strategies for water resource management to downstream and upstream communities.

Recovering nutrients, water and energy from domestic waste streams, including wastewater and faecal sludge, is slowly gaining momentum in low-income countries. Resource recovery and reuse (RRR) offers value beyond environmental benefits through cost recovery. An expected game changer in sanitation service provision is a business model where benefits accrued via RRR can support upstream sanitation services despite the multitude of private and public stakeholders involved from waste collection to treatment. This paper shows options of how resource recovery and reuse can be an incentive for the sustainable sanitation service chain, by recovering costs where revenue can feed back internally or using generated revenues from reuse to fill financial gaps across the service chain to complement other supporting mechanisms for making waste management more attractive.

Phosphorus (P) is a critical, geographically concentrated, nonrenewable resource necessary to support global food production. In excess (e.g., due to runoff or wastewater discharges), P is also a primary cause of eutrophication. To reconcile the simultaneous shortage and overabundance of P, lost P flows must be recovered and reused, alongside improvements in P-use efficiency. While this motivation is increasingly being recognized, little P recovery is practiced today, as recovered P generally cannot compete with the relatively low cost of mined P. Therefore, P is often captured to prevent its release into the environment without beneficial recovery and reuse. However, additional incentives for P recovery emerge when accounting for the total value of P recovery. This article provides a comprehensive overview of the range of benefits of recovering P from waste streams, i.e., the total value of recovering P. This approach accounts for P products, as well as other assets that are associated with P and can be recovered in parallel, such as energy, nitrogen, metals and minerals, and water. Additionally, P recovery provides valuable services to society and the environment by protecting and improving environmental quality, enhancing efficiency of waste treatment facilities, and improving food security and social equity. The needs to make P recovery a reality are also discussed, including business models, bottlenecks, and policy and education strategies.