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Gravity dam is one of the biggest structures built on the Earth. It is known as a life line structure, as it serves the purpose of irrigation, hydro-electric power generation, flood control, domestic and industrial water supply etc., which are important for human existence. This makes dam as a reliable structure. For this reason, dam should always be designed for highest safety. Dam is one of the hydraulic structures constructed to serve particular functions. It is a water control feature to impound water supply, to divert water from a water course, or to raise the elevation for water body. In supplying the water to the consumers, a dam holds it from flowing into the pipe, tunnel and conduit. Earth fill dams are a good alternative to dugouts where larger volumes of water must be stored at a reasonable cost and suitable site conditions exist. Proper design and construction is essential for dams; otherwise they will fail from washouts or seepage losses. If water quantity is your main priority, then a dam could be the best option. If better water quality is the important factor, a dugout is probably a better option. Take the time to properly plan, construct, inspect and maintain your dam, and it will be a valuable water resource for your farm for many years to come. However, poor management of dams can cause problems and disasters in terms of safety of dam and how it affects the people and the environment. This study focuses for conducts how the design, operator and maintenance of dam to be ensure it is safety.

The concept of a green economy has gained currency in recent years as a paradigm for promoting economic growth and increased well-being while protecting the environment and contributing to poverty alleviation. There is no common definition of green economy, but the term clearly emphasizes the economic dimension of sustainability. Not only do the environmental (stewardship) and economic (growth) dimensions coexist in the green economy, but they are also complementary and mutually reinforcing strategies to achieve development. Water scarcity, pollution, and other water related environmental and ecological problems have been increasing rapidly in many areas of the world. Water demand management or making better use of the water we have as opposed to augmenting supply is increasingly proposed as a way of mitigating water scarcity problems. Although the achievements of irrigation in ensuring food security and improving rural welfare have been impressive, past experience also indicates problems and failures of irrigated agriculture. In addition to large water use and low efficiency, environmental concerns are usually considered the most significant problem of the irrigation sector. Environmental problems include excessive water depletion, water quality reduction, water logging and salinization. In some basins (water resources), excessive diversion of river water for irrigation (and other uses) has brought environmental and ecological disasters to downstream areas, and groundwater pumping at unsustainable rates has contributed to the lowering of groundwater tables and to salt water intrusion in some coastal areas. Many water quality problems have also been created or aggravated by changes in stream flows associated with agriculture’s consumptive uses. Moving water away from agriculture to uses with higher economic value is one of the main measures widely seen as desirable. This apparent misallocation is often attributed to the failure of government to allocate water rationally. This paper focuses on achieving a sustainable balance between irrigation management and sustainable development and water investments.

Plant nutrition balance plays a major role in the universal need to increase food production to meet the demands of the growing world population. Fertilizer application resulted in marked crop yield increases, which for most crops were more than hundred. The extent to which fertilizers are used still differs considerably between various regions of the world. Soil nutrient status is widely constrained by the limited use of inorganic and organic fertilizers and by nutrient loss mainly due to erosion and leaching. Many small holder farmers do not have access to synthetic fertilizer because of high price of fertilizers, lack of credit facilities, poor distribution, and other socio-economic factors. Consequently, crop yields are low, in fact decreasing in many areas, and the sustainability of the current farming system is at risk. Therefore, the aim of this review was to review the role of integrated Plant nutrition balance management for improving crop yield and enhancing soil fertility under small holder farmers in dry areas, and recommend the appropriate approaches for enhancing soil fertility and increasing crop yield for small holder farmers in dry and semi-dry areas. These are the key challenges of adoption in the scaling up of such alternative soil fertility management practices to millions of small-scale farmers. There is a need, therefore, for research and extension to sort out issues of adoption and scaling up of the available options. In order to address soil fertility problems, potential synergies can be gained by combining technical options with farmers’ knowledge as well as training of farmers and development agent on new soil fertility management approaches. So, the results of this review showed that, the integrated application of organic and inorganic fertilizers improve productivity of crops as well as the fertility status of the soil. The reasons for this are many, which include access or availability of inputs, use of organic resources for other purposes in place of soil fertility, nutrient balancing, collecting, transporting and management of organic inputs and economic returns of investments.

Integrated water management means putting all the pieces together. Social, environmental, and technical aspects must be taken into consideration. Issues of concern include: providing forums; Reshaping planning processes; Coordination of land and water resources management; Identify the links between water sources and water quality; Develop protocols for integrated watershed management; Addressing institutional challenges; Protecting and restoring natural systems; Reformulation of existing projects; Knowing the views of society; Clarify education and communication risks; Technology standardization and policy; Form partnerships and emphasize preventive measures. The highest priority for water resource management is to increase the demand for water with limited water resources. Water resources are the foundation for sustainable development, so a sustainable approach must be based on the use and management of water resources. In the twenty-first century, the world faces a major water crisis. The problems stem from errors in the management of water resources. Consequently, the sustainable use of water resources is crucial for humanity. Sustainable development is defined as the goals of supply and today's needs without jeopardizing the goals and requirements of future generations. Long-term goals should be considered instead of short-term goals in assessing water resources. This approach forms the idea of integrated water resource management for horticultural crops. This paper describes the evolution of water use in relation to productivity, how irrigation systems have developed and managed, and a strategy to explore challenges and opportunities for water conservation in horticulture crops.