Appraisal of Groundwater Status Applying the CCME WQI Model

¹ Ph.D Researcher at the National University of Uzbekistan Named after Mirzo Ulugbek, Tashkent 100174, Uzbekistan, ORCID: 0009-0007-3394-3661, Email: ni.rajabova@nuu.uz
² National Water Research Center, Drainage Research Institute, Delta Barrage, Kaliobia 13621, Egypt, ORCID: 0000-0001-7999-4172, E-mail: Alaafg@gmail.com
³ State Establishment Institute of Hydrogeology and Engineering Geology, Uzbekistan, ORCID: 0000-0001-6379-6112, Email: shahriyortoshev@mail.ru
⁴ Ph.D Researcher at University of Benin Benin City, Nigeria, ORCID: 0009-0000-2542-7105, E-mail: graceobasuyi80@gmail.com

^* Corresponding author: ni.rajabova@nuu.uz, (Phones: +998 93 203 75 32 or +998 50 120 75 32)

Abstract

Both natural and human-induced factors increasingly threaten groundwater quality in arid regions. This study evaluates the quality of shallow natural groundwater (10–25 meters deep) in the Amudarya province, Republic of Karakalpakstan, Uzbekistan. The objective was to determine whether the groundwater in this region is safe or poses potential health risks. Water samples were collected from eight different sites and analyzed for nine physicochemical parameters, including total hardness (TH), chloride (Cl^-), sulfate (SO ^2-), total dissolved solids (TDS), fluoride (F^-), iron (Fe²⁺), nitrate (NO₃^-), copper (Cu²⁺), and pH. Standard laboratory techniques were employed for testing, and the Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI) model was applied for integrated assessment. The results revealed that several parameters — particularly TH, TDS, Cl^-, and SO₄^2- — exceeded World Health Organization guidelines. The overall water quality was rated as ‘Marginal,’ indicating restricted usability and potential health risks. Furthermore, a comparative analysis of ten international studies reveals that Amudarya’s marginal WQI values fall within the lower-middle category globally, primarily due to salinization in semi-arid agroecological settings. This contrasts with regions affected by toxic metal contamination, highlighting distinct geographical and ecological drivers of water quality degradation.