EVALUATING THE EFFICIENCY OF A CONSTRUCTED WETLAND SYSTEM FOR INDUSTRIAL AND DOMESTIC WASTEWATER TREATMENT IN SOUTHERN PUNJAB, PAKISTAN

Abstract

Water scarcity has become an increasingly urgent global issue, fueled by rapid population growth, industrialization, and inefficient water management. The World Water Assessment Programme predicts that nearly two-thirds of the world’s population could face severe water shortages by 2025, with almost half affected by 2030. In Pakistan, per capita water availability has plummeted from 5000 m³ year⁻¹ in 1951 to roughly 1100 m³ year⁻¹, placing the country under critical water stress.

Constructed wetlands (CWs) have emerged as cost-effective, nature-based solutions for wastewater treatment, particularly in areas challenged by pollution and freshwater scarcity. This study was conducted at C-Block, MNS-University of Agriculture, Multan, where a surface flow constructed wetland system was established to treat wastewater from the Wali Muhammad Distributary—a canal contaminated with untreated domestic and industrial effluents. The wetland consisted of a series of vegetated ponds designed to promote natural filtration processes. Wastewater samples were collected weekly over a three-week period and analyzed for key physico-chemical parameters. Statistical analyses were performed using R software, with significance assessed via t-test at p < 0.05.

The system achieved substantial reductions in various parameters: pH (16%), electrical conductivity (93.30%), carbonate (82%), bicarbonate (66%), total dissolved solids (75%), total solids (84.43%), total suspended solids (75%), biological oxygen demand (84.23%), chemical oxygen demand (39%), potassium (53%), sodium (75%), and calcium (68%). These findings underscore the high pollutant removal efficiency of constructed wetlands and highlight their potential as a sustainable strategy for wastewater treatment and water resource management.