Conserving water and providing for the future generation is one of the most important principals established on the agenda concerning sustainable development goals. The aim of the paper is to evaluate the sustainability of the quantity and quality of water sources for Erbil City, as well as their safety and security based on the standard limitations. Therefore, the study computed the adapted scale of measuring water quantity and the demand of water and then evaluated the collected data from the water directorates related to both surface water and groundwater for the studied area. The study focused on the management of water supply and main factors that affected the lack of the sustainability. The next step was the planning of appropriate solution for those problems, such as avoiding drilling of illegal groundwater wells and managing water sector that made the poor water management as well. The use of additional surface water accomplished with the construction of extra water treatment plants was seen as an alternative to consuming groundwater. Reusing of processed sewage for various consumption and recharging of groundwater was considered as sustainable strategy and management for the water field in Erbil City.

Concrete is one of the most reliable, durable, and desired construction materials. It became the second most used material after water in the world. Many studies and investigations reported that the amount of CO2 released into the atmosphere is nearly 1 ton in the production of 1 ton of cement, which contributes to 5-7 % of total CO2 emissions worldwide. Geopolymer concrete (GPC) is a new development in the world of concrete, which does not need to use cement. The most used materials in geopolymer are by-products such as fly ash, ground granulated blast furnace slag, silica fume, etc. Industrial waste materials are a great problem for human health, environment, and scarcity of land, therefore, reusing them in GPC manufacturing can be seen as a great advantage. Fortunately, most of the recent research concludes that most by-products exhibit similar or better durability, mechanical and physical properties when compared to ordinary concrete. Therefore, GPC became a good sustainable engineering material with many advantages over conventional concrete, such as high early strength, excellent resistance to chemical attacks and steel reinforcement corrosion, elimination of water curing, low cost, etc. This paper reviews the process of geopolymer concrete, constituents, types, properties, durability, and particular applications.

The research presents an overview on sludge types, characteristics, and methods of treatment. Additionally, using the sludge as an energy source for future plans was studied as well. The paper focused mainly on analyzing different sludge characteristics based on the previous studies. Wastewater sludge produced from the primary, secondary, and tertiary treatment processes was analyzed. It was mainly composed of many organic and inorganic materials. Some of the materials were removed by physical and other required chemical or biological processes. Most of the sludge was solid, semi-solid, and muddy with the harmful substances such as proteins, phenols, and hazardous materials. The study explained different methods of energy production as well. At the end, it was concluded that every type of sludge could provide energy and be a basic financial product for the selected area, and keep environment safely and healthy as well. The calculated quantity of dry sludge for 1,000,000 inhabitants in Erbil City, Kurdistan Region-Iraq, was 50,000 kg/d, which produced calorific value of 9.5 · 107 K. cal./day. Furthermore, the essential area for under drain sand bed area was 5,100 m2 .