Search

The potential impacts resulting from climate change will cause significant global problems, particularly in underdeveloped nations where the effects are felt the most. Techniques for harvesting water such as small dams provide an alternative supply of water and are adaptive solutions to deal with water scarcity in the context of future climate change. However, it is difficult to determine how rainwater harvesting (dams) may be impacted by climate change since general circulation models (GCMs), widely utilized for predicting potential future climate change scenarios, work on an extremely large scale. The primary aim of this research was to quantify the effect of climate change on water availability at the catchment scale by statistically downscaling temperature and rainfall from the GCMs. Then, using a water harvesting model, the performance of the Abila Dam in Iraq's western desert was evaluated in both the current climate (1990–2020) and various future climate change scenarios (2020–2100). Precipitation generally decreases as the annual temperature increases. To simulate future water availability, these changes in meteorological factors were incorporated into the water harvesting model. In total, 15% or less of net storage might fulfil the whole storage capacity during the baseline period, whereas it is 10% in RCP 2.6 in 2011–2040 for future scenarios. In contrast, RCP 8.5 will be able to meet water needs at a pace of 6% in 2011–2040. The findings of this study proved that the Al Abila dam will be unable to supply the necessary water for the area surrounding the Al Abila dam in the future scenarios. [ABSTRACT FROM AUTHOR]

Rainwater Catchment System Reliability (RCSR) is the chance that a system will deliver the required water for an interval of time. Rainwater Harvesting (RWH) is gaining popularity as a potential alternative water source for household or agricultural use. The reliability of the Al Abila dam in the western desert of Iraq was analyzed using a water budget simulation model and two explanations of reliability, time-based reliability, and volumetric reliability. To evaluate rainwater harvesting system performance, comprehensive software utilizing a method for everyday water balance using data from 20 years of daily rainfall. According to the findings, volumetric reliability, and for the three climate scenarios (wet, average, and dry year), increased as the storage volume increased until a threshold accrued on the storage capacity of 11.7 × 105 m3. While time-based reliability shows an increase up to a storage volume of 10.2 × 105 m3. Volumetric reliability of roughly 34–75% may be achieved, while only 14–28% time-based reliability may be achieved. Water saving efficiency decreases with increasing demand fraction, while the runoff coefficient has no significant influence on water effectiveness. While growing storage fraction value increases the effectiveness of water conservation and the value of the runoff coefficient influences the water saving efficiency. For both cases, water saving efficiency for the dam does not reach 50%. Using daily rainfall data, the technique given in this paper might be applied to predict water savings and the RWH systems' reliability in different arid and semi-arid areas. [ABSTRACT FROM AUTHOR]

Groundwater is one of the most important water resources in Iraq, so efficient management of storage, recharge, and consumption rates is required, for maintaining the sustainability of groundwater supplies. Some of the most valuable methods for ensuring the long-term sustainability of groundwater aquifers are those that provide artificial recharge. This study was conducted to determine the effect of artificial recharge on groundwater levels and quality in Iraq's Dibdibba unconfined aquifer, utilizing groundwater modeling system software (GMS). Reclaimed water (tertiary treatment) from Kerbala's central wastewater treatment plant (WWTP) was used as raw water to recharge the aquifer. The effects of this artificial recharge were determined using built-up groundwater flow (MODFLOW) and dissolved transport (MT3DMS) simulation models. Model calibration and validation were implemented based on groundwater monitoring data from 2016 to 2017. The model matched observed elevations at R2 = 0.96 for steady state and R2 = 0.92 in transient state simulations. After the 3D numerical model was calibrated and validated, two scenarios were explored based on the daily production of 5000 and 10,000 m3/d from Karbala's WWTP. The results indicated that the pumping of the treated wastewater through the pond would increase water levels by more than 20 cm for more than 78.2 and 110 km2 for pumping rates of 5000 and 10,000 m3/day, respectively. More than 40 km2 would be added (reclaimed) to the agricultural areas in the region as a result of the use of artificial recharge using a pond. Groundwater quality was also improved, as the TDS decreased by more than 55%, down to 1900 ppm, and the EC decreased by more than 68%, down to 1500 µ.S/cm. The findings of this study can assist decision-makers in developing strategies to reduce water scarcity and adapt to climate change. [ABSTRACT FROM AUTHOR]

The objective of this study is to produce suitability maps for potential rainwater harvesting techniques (RWHT) in the West Bank (WB), Palestine. These techniques aim to reduce water scarcity, which is a major problem for the conservation of water resources in the area. Based on literature reviews and expert recommendations, seven RWHts were selected (runoff basin system, contour ridges, cisterns, eyebrow terrace, check dam, on-farm pond, and bench terraces). Analysis methods performed in the Arc GIS environment include spatial analysis and data reclassification. Other calculations include multi-criteria analysis for assigning suitability. Five criteria (rainfall, runoff, land use, slope, and soil texture) for RWHt were analyzed to produce a suitability map for each technique. The results show that runoff basin systems in the northeast and southwest of WB are the most suitable, with about 50% of the area of WB moderately suitable for this technique, while 70% of the area of WB is very suitable for the contour ridge technique. Furthermore, this analysis shows that almost 50% of the WB is very suitable for cisterns. Sixty percent of the area is very suitable for on-farm puddling, especially in the north and southwest of WB. The areas with high suitability for the different techniques comprehensively cover the WB, as shown in the RWHt suitability maps and the integrated map. Nevertheless, this approach can help decision makers in making an initial selection of RWH techniques suitable for their region. [ABSTRACT FROM AUTHOR]

Arid and semi-arid regions around the world face water scarcity problems due to lack of precipitation and unpredictable rainfall patterns. For thousands of years, rainwater harvesting (RWH) techniques have been applied to cope with water scarcity. Researchers have used many different methodologies for determining suitable sites and techniques for RWH. However, limited attention has been given to the evaluation of RWH structure performance. The aim of this research was to design a scientifically-based, generally applicable methodology to better evaluate the performance of existing RWH techniques in (semi-) arid regions. The methodology integrates engineering, biophysical and socio-economic criteria using the Analytical Hierarchy Process (AHP) supported by the Geographic Information System (GIS). Jessour/Tabias are the most traditional RWH techniques in the Oum Zessar watershed in south-eastern Tunisia, which were used to test this evaluation tool. Fifty-eight RWH locations (14 jessr and 44 tabia) in three main sub-catchments of the watershed were assessed and evaluated. Based on the criteria selected, more than 95% of the assessed sites received low or moderate suitability scores, with only two sites receiving high suitability scores. This integrated methodology, which is highly flexible, saves time and costs, is easy to adapt to different regions and can support designers and decision makers aiming to improve the performance of existing and new RWH sites. [ABSTRACT FROM AUTHOR]

Water scarcity is a major problem in the arid climate of Iraq's Western Desert and people struggle to manage the precarious water supply. Harvesting rainwater is one sustainable method that can be used to increase the supply of water. Rainwater harvesting systems (RWH) are considered to be sustainable "if they can continue collecting, utilising, and consuming natural water resources for maximum livelihood development". This study assessed the sustainably of the Al- Abila dam in Iraq's Western Desert by determining its level of functionality in harvesting water and using it effectively. The reliability of the water supply and its potential productivity and water use efficiency were investigated as well. The balancing storage at the end of each runoff shows that dam storage of this magnitude is insufficient to fulfil the water demand. This research highlighted constraints that have affected system functioning or sustainability and provided suggestions and recommendations for risk-managed rainwater harvesting system installation methods and designs. The water conveyance factor and adequacy of the system were low, with 60% conveyance losses. This research helps policymakers to conduct large-scale, high-level assessments and answer basic problems about small earth dam development and management in Anbar's Western Desert. [ABSTRACT FROM AUTHOR]

Water resource management and the investigation of the quality and quantity of groundwater and surface water is important in the Kurdistan Region of Iraq. The growing population, as well as agricultural and industrial projects, consume huge amounts of water, especially groundwater. A total of 572 ground and surface water samples were collected for physicochemical analysis to determine the availability and quality of the water in the Kurdistan region. The physicochemical parameters such as pH, electrical conductivity, and total dissolved solids were analyzed to evaluate the suitability of the water for different purposes like livestock, irrigation, and agriculture. GIS-based multi-criteria decision analysis (MCDA) was used to determine the suitability map of water for irrigation purposes. Most of the groundwater samples were suitable for irrigation except for some samples from Erbil City, especially those taken in the Makhmur district, and samples from some small areas in the cities of Sulaymania and Duhok. All groundwater samples were acceptable for all types of agricultural crops, except for 15 well samples that were determined not to be usable for fruit crops. However, this water was acceptable for livestock and poultry. Most of the water wells provided freshwater except for 36 deep wells, which supplied slightly brackish to brackish water. Water samples were found to have low to medium salinity levels except for 26 well samples and one spring sample that had high salinity levels, and 2 well samples with very high salinity levels. Most of the samples had an excellent to good water classification except for 85 samples classified as permissible, 8 classified as doubtful, and 4 classified as unsuitable for irrigation according to the Todd classification. According to the Rhoades classification, all water samples were non-saline to slightly saline except for 11 samples that were moderately saline. [ABSTRACT FROM AUTHOR]