Ali Abbasi

Rising demand for urban water consumption, especially for household uses, has led to a water crisis in various cities around the world. The amount of household water consumption, as the most important part of urban water use, is significantly affected by the consumers’ behaviours and water saving equipment used. Therefore, it is necessary to mitigate the household water demand by applying effective strategies such as promoting the water conservation culture and installing water saving appliances. For this purpose, consumers’ behaviours should be evaluated and various types of household water consumptions should be ranked. In this research, by distributing questionnaires among the citizens of Mashhad city, the consumer behaviours were evaluated. Confirmatory factor analysis (CFA) was applied to examine the similarity of people's consumption behaviours in various household uses. The results showed that people's consumption behaviours are different. By defining the impact coefficient index and the average impact coefficient index, various types of household water consumptions were ranked using Friedman and Wilcoxon statistical tests. Based on the results, changing consumption behaviours in bathing has the highest efficiencies on reducing water consumption. Dishwashing, using the washing machine and sanitation (toilet) were jointly ranked second. Car washing and tooth brushing were both equally important and ranked third.

Rainwater harvesting (RWH) has been recognized as one of the most reliable and efficient methods for water supply, especially in arid and semi-arid regions (ASARs) facing freshwater scarcity. Nevertheless, due to the inherent uncertainty of input data and subjectivity involved in the selection of influential parameters, the identification of RWH potential areas is a challenging procedure. In this study, two approaches for locating potential RWH sites were implemented. In the first approach, a frequently-used method of the multi-criteria decision analysis and geographic information system (MCDA-GIS) was utilized, while, in the second approach, a novel strategy of integrating the soil and water assessment tool (SWAT) model as a hydrology model into an MCDA-GIS method was proposed to evaluate its performance in locating potential RWH sites. The Mashhad Plain Basin (MPB) was selected as a case study area. The developed potential RWH maps of the two approaches indicated similar patterns for potential RWH areas; in addition, the correlation coefficient (CC) between the two obtained maps were relatively high (i.e., CC = 0.914) revealing that integration of SWAT as a comprehensive hydrologic model does not necessarily result in very different outputs from the conventional method of MCDA-GIS for RWH evaluation. The overlap of developed maps of the two approaches indicated that 3394 km² of the study area, mainly located in the northern parts, was identified as high-potential RWH areas. The performed sensitivity analysis indicated that rainfall and slope criteria, with weights of 0.329 and 0.243, respectively, had the greatest sensitivity on the model in the first approach while in the second approach, the criterion of runoff coefficient (with weights of 0.358) had the highest impact. Based on results from the identification of the potential locations for conventional RWH techniques, pond and pan techniques are the most proper options, covering high-potential areas of RWH more effectively than other techniques over MPB.

In recent years, in addition to water resources’ quantity, their quality has also received much attention. In this study, the quality of the urban water distribution network in northwestern Iran was evaluated using the water quality index (WQI) method. Then, some important trace elements were investigated, and finally, the health risk assessment was evaluated for both carcinogenic elements (Ni, Cd, Cr, Pb, and As) and non-carcinogenic elements (Ca, Mg, Na, K, F, NO₃, and Cu) using carcinogenic risk (CR) and hazard quotient (HQ), respectively. In the present study, the WQI was calculated based on both World Health Organization (WHO) and Iranian drinking water standards. Comparing the results of these standards revealed that the WQI based on the Iranian standard was slightly higher. Regarding the calculated WQI for the study region, the status of water quality for drinking consumption is in the good water quality class (25 < WQI < 50). It was observed that Cu and Cd have the highest and lowest concentrations in all sampling points, respectively. Hazard Index (HI) results showed that the non-carcinogenic substances studied had a low risk for both adults and children (<1.0). However, the CR results showed that Ni, Cd, and As were above the desired level for both children and adults. The results of this study can be applied for efficient water management and human health protection programs in the study area.

The growth of Iran’s agricultural sector in the past few decades has exerted enormous pressure on its aquifers. There is a strong disparity between economic development and natural resource endowments, which threatens water and food security. In this paper, we used a multiregional input–output (MRIO) framework to assess the virtual water flows in Iran. We also estimate the internal and external water footprint of regions compared to their water availability. The results show that the northern part of the country, with no water scarcity, imported virtual water through the trade of goods and services, while severely water-scarce regions were net virtual water exporters. Iran had a net export of 1811 Mm³ per annum. While blue water resources (surface and groundwater) accounted for 92.2% of the national water footprint, 89.1% of total exports were related to the agriculture sector, contributing to only 10.5% of the national income. The results suggest that policy-makers should reconsider the current trade policy regarding food production liberalization in order to make Iran’s limited water resources available for producing industrial goods, which can contribute more to the economy.

The strong desire for achieving self-sufficiency in developing and mostly water-scarce regions has endangered socioeconomic and environmental sustainability. South Khorasan is particularly exposed to such insecurities, largely due to its limited water resource endowments and its comparatively intensive agriculture. In this paper, we apply the water footprint accounting method (WFA) along with a regional input–output (IO) model to analyze the efficiency of the total (direct + indirect) water consumption in different economic sectors and water footprint of the region in 2011. Results show that agriculture is responsible for more than 95% of water consumption in the area, while it accounts for just 27% of value-added. Additionally, this sector has the largest contribution to water footprint composition (92%) when compared to other sectors. Three water-saving scenarios are simulated by the use of IO economic model and water footprint accounting method. Applying the proper cropping pattern has the greatest impact on water conservation with 348.46 Mm³ per year. A 10% increase in water productivity contributes nearly twice as much as reducing the exports and increasing the imports of agricultural crops by 10% in saving water with 115.23 and 65.49 Mm³, respectively. The most significant contribution in each water-saving strategy comes from the agriculture sector since it has the largest direct and indirect water-use coefficient. The results of this study can help local policymakers take appropriate measures to improve the efficiency of water resource utilization, taking into consideration social, economic, and environmental sustainability.

Increasing water demands, especially in arid and semi-arid regions, continuously exacerbate groundwater resources as the only reliable water resources in these regions. Groundwater numerical modeling can be considered as an effective tool for sustainable management of limited available groundwater. This study aims to model the Birjand aquifer using GMS: MODFLOW groundwater flow modeling software to monitor the groundwater status in the Birjand region. Due to the lack of the reliable required data to run the model, the obtained data from the Regional Water Company of South Khorasan (RWCSK) are controlled using some published reports. To get practical results, the aquifer boundary conditions are improved in the established conceptual method by applying real/field conditions. To calibrate the model parameters, including the hydraulic conductivity, a semi-transient approach is applied by using the observed data of seven years. For model performance evaluation, mean error (ME), mean absolute error (MAE), and root mean square error (RMSE) are calculated. The results of the model are in good agreement with the observed data and therefore, the model can be used for studying the water level changes in the aquifer. In addition, the results can assist water authorities for more accurate and sustainable planning and management of groundwater resources in the Birjand region.