Proposing a Wetland-Based Economic Approach for Wastewater Treatment in Arid Regions as an Alternative Irrigation Water Source

Abstract

Point and nonpoint wastewater sources have a detrimental, negative effect on agriculture, soil, surface, and groundwater supplies. In this research, a wastewater treatment system made up of a sedimentation tank, a horizontal subsurface flow constructed wetland (HSSF-CW), a vertical subsurface flow constructed wetland (VF-CW), and a storage tank was proposed, designed, and cost estimated. Small populations in underdeveloped nations with dry and semi-arid climates can use the treatment system as an affordable construction, maintenance, and operational solution for wastewater treatment. The system will protect agricultural lands and groundwater from pollution. The system can service 6000 capita and has a wastewater discharge of 780 m3/d in the developing arid region in El-Moghra Oasis western desert of Egypt, where the 1.5 million acres used for the land reclamation project based on groundwater irrigation. The relaxed tanks in a series model based on the areal loading rates and background pollutants concentrations (P-K-C*) was utilized to size the HSSF and VF-CWs. The results indicated that the HSSF-CW design treatment surface area was 2375 m2, and the hydraulic surface loading (q) and hydraulic retention time (RT) were 0.33 m/d and 0.55 d, respectively, and utilizing Phragmites australis and Papyrus for the biological treatment. The expected overall cumulative removal efficiencies were 96.7, 70, and 100% for the biological oxygen demand (BOD), total phosphors (TP), and fecal coliforms (FC), respectively. The VF-CW indicates that there was a 2193 m2 design treatment surface area, q = 0.36 m/d, and RT of 0.63 d. The expected BOD, TP, and FC removal efficiencies were 75, 33.3, and 92.7%, respectively. In order to simplify the design stages and the cost estimation, design and investment cost curves were established for a population range from 500 to 9000. The total monthly water loss due to evapotranspiration for the HSSF and VF-CWs indicates a range from 3.7 to 8.5%, respectively. The total investment cost analysis for the proposed system corresponding to 780 m3/d wastewater discharge of indicates a total investment cost of EUR 146,804 and EUR 24.46/per-capita equivalent (P.E). This approach can be used by decision makers in the Mediterranean region and Middle Eastern countries to improve the water quality using social and economic criteria, leading to the effective implementation of ecological restoration projects as a low-cost treatment system and adding a nonconventional water source that can be used in irrigation.

A Critical Review of Green Approach on Wastewater Treatment Strategies

“…Anaerobic digestion is a biological process that converts organic matter in wastewater into biogas and nutrient-rich sludge. The biogas can be used as a renewable energy source, while the sludge can be used as a fertilizer (Oscar, and Caren, 2021;Gabr et al, 2023). In recent decades, a great deal of thorough research has been done on a novel technology called bioremediation of different waste waters.…”

“…Maintenance requirements: Constructed wetlands require ongoing maintenance to ensure that they are functioning properly. Maintenance can be timeconsuming and costly (Gabr et al, 2023).…”

Determination of the Canal Discharge Capacity Ratio and Roughness to Assess Its Maintenance Status: Application in Egypt

“…Additionally, it has meteorological characteristics such as significant daily temperature swings between the lowest and highest temperatures. The temperature varies greatly between summer and winter, with an average yearly temperature of roughly 22 • C [42][43][44]. Additionally, 33.3 mm of rainfall precipitates on average throughout the winter months [41].…”

Assessment of Stormwater Quality in the Context of Traffic Congestion: A Case Study in Egypt

“…According to the Falkenmark Index [8], the nation was already functioning below the level of water scarcity; the total renewable water resource per person was 628 m 3 /year, a quantity that is currently under tremendous strain due to a growing population that has been expanding at a rate of over 1.8 to 2.1% annually since 1989 [1]. Therefore, to address this issue, Egypt should think about using natural and unconventional water resources, such as deep groundwater extraction, seawater desalination, and wastewater treatment [9][10][11][12]. One alternative is rain harvesting.…”