Spatial Analysis of Groundwater Quality by Analytical Hierarchy in Shoob، Azal and Al-safia Districts in the Capital Sana'a

Abstract

The study aimed to determine the spatial variation of groundwater quality using the hierarchical analysis method and weighted matching in the (ArcGIS) program. To achieve the objectives of the study، the quantitative analytical approach was used to perform spatial and statistical analyzes of field study data and laboratory analyses. This study relied on collecting samples from (75) wells for biological examinations and (51) wells for physical and chemical examinations; To analyze the physical، chemical and biological properties in the laboratory، and the results of the laboratory analysis were used to produce digital maps showing the quality of groundwater in the study area. The study concluded that the water of hazardous and very low quality is concentrated the west of the study area in each of Al-Saadi neighborhood Al-Safia district and the neighborhood of Misik and Bani Qushayb Shu’ub district. ، fluoride، nitrates، total hardness، calcium، dissolved salts)، and the low water quality occupied (24.9%) of the total area of ​​the study area، and appears largely the west of the study area in the following neighborhoods: (Horrible House، Chicken Village، Al-Sufi House، Bab Al-Salam، Taiz Street، Al-Tadamon Al-Shamaliya، and Al-Fatah Al-Shamalia)،As well as the north of the Directorate of Shu’ub the Raslan neighborhood and the north-east of the district the Sa’wan neighborhood and the villages of Al-Gharza، Al-Asha and Al-Tawather. This water is considered unfit for drinking، due to the concentration of elements (total and fecal coliforms، color، turbidity، total alkalinity، total hardness). As for the rest of the study area، the water quality ranged from excellent to good، and it is water suitable for various human uses. Groundwater of excellent quality constituted (27%) of the total area of ​​the study area، and it is found the south and southeast of the study area and other parts As for the areas with good quality of groundwater، they cover the largest percentage، reaching (43.2%) of the total area of ​​the study area. They are generally concentrated in the northern half of the study area the Directorate of Shaub and parts of the middle of the districts of Azal and Al-Safia. The study recommended conducting periodic laboratory analyzes of well water to identify areas of low quality and conducting appropriate treatments to raise the efficiency of groundwater quality، and reduce pollution sources.