A novel framework for Low Impact Development (LID) planning and runoff control in urban watersheds

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Evaluation of aquifer vulnerability using PCA technique and various clustering methods

One of the significant challenges in applying vulnerability methods is their dependence on the same weights and ranks for each parameter. Therefore, to modify these methods, a clustering technique independent of ranks and weights and based only on the nature of data was used in the first step in this study for vulnerability mapping. Moreover, Principal Component Analysis (PCA) was employed to consider all parameters and select the effective ones. After reviewing the literature on different vulnerability assessment methods, 14 parameters involved in determining the vulnerability of the Varamin Aquifer in Iran were selected. The principal component analysis revealed that seven of them were the major ones. In the next step, the vulnerability map of the aquifer was prepared by using the C-Means, the K-Medoids, and the K-Means clustering methods. It was found that the fuzzy C-Means clustering method outperformed others with a CI of 260

Multi-parameter risk mapping of Qazvin aquifer by classic and fuzzy clustering techniques

This study proposes a new approach to establish a multi-parameter risk mapping method by employing the K-Means clustering technique. Accordingly, spatial assessment of arsenic (As), nitrate (NO3) and total dissolved solids (TDS) were carried out based on the type of land use to estimate contamination potential in an aquifer. Since risk mapping is always associated with the occurrence probability of a phenomenon, pollution occurrence probability was then obtained using the fuzzy C-means clustering. The results reveal that NO3 and As contamination levels increase from the first cluster (C1), covers 22.3% of the aquifer, to C5 encompassing 35.1% of the aquifer devoted to extensive industrial and agricultural activities. Fuzzy clustering results show that the pollution occurrence probability in each aquifer cell varied from less than 30 to more than 90%. Moreover, the results show, industrial and agricultural land uses cover about 70% of the areas with high risk of contamination

Introduction of Life Cycle Techniques in Evaluating Water Distribution Systems

Our generation is facing the daunting challenges of climate change and growing pressure on the environment; Challenges caused by human activities. Considering these environmental conditions and their relationship with social and economic challenges, to achieve the United Nations sustainable development goals, comprehensive and strong tools are required to make decisions to identify the solutions supporting sustainable development in the best way. Decisions should have a systematic perspective, and consider the life cycle and all its related impacts. Life cycle assessment (LCA) is a tool possessing these characteristics. In this study, the life cycle assessment method is introduced first and then, several applications of this method in water distribution systems are examined using some articles. The review of previous studies showed that replacing the gravity transfer of water by pumping can reduce greenhouse gas emissions by 64-81%. Also, choosing the right type and diameter for the pipes of the water distribution network - which will reduce leakage from the network - will increase the life of the network and save up to 75% of costs. Finally, recycling the network after its useful life has significant positive environmental effects and can reduce the potential of human poisoning and pollution of natural resources by 60-88%

Groundwater Extraction Reduction within an Irrigation District by Enhancing the Surface Water Distribution

Today, in developing countries, the low surface water distribution efficiency and the lack of supplying water needs of farmers by surface water resources are compensated by excessive aquifer water withdrawal. This mismanagement has caused a sharp drop in the groundwater level in many countries. On the other hand, climate change and drought have intensified the pressure on water resources. This study aims to evaluate novel strategies for developing surface water distribution systems for stress reduction of the Najafabad aquifer in Isfahan, central plateau of Iran. The performance of several strategies for agricultural water distribution and delivery, such as hydro-mechanical operating system, manual-based operating system, and centralized automatic operating system, was evaluated in this study. In the first step, two indices, i.e., water distribution adequacy and dependability, were obtained using a flow hydraulic simulation model. Then, the water distribution adequacy map and amount of reduction in the water withdrawal of existing wells were determined for each strategy. Finally, using the MODFLOW groundwater simulation model, the changes in groundwater levels due to the normal and drought scenarios (15 and 30%) were extracted during five years for each strategy. The findings for the normal scenario showed that the centralized automatic operating system strategy had the most significant impact on agricultural water management in the surface water distribution system with a 30% increase in agricultural water distribution adequacy index compared to the current situation. This strategy increased the groundwater level by 11.6 m and closed 35% of the groundwater wells. In this scenario, the hydro-mechanical operating system strategy had the weakest performance by increasing the aquifer level by only 1.31 m. In the 15% and 30% drought scenarios, the centralized automatic operating system strategy exerted the best performance among other strategies by increasing the aquifer water level by 10.18 and 9.4 m, respectively, compared to the current situation. Finally, the results showed that the spatial segmentation of the aquifer exerted better efficiency and better monitoring in the more susceptible regions