Constructed Hybrid Wetlands
Restoration of Eco-hydrology at the premises of PCRWR
Why Constructed Wetlands
To address the water scarcity challenges under changing climate, it is essential to utilize the non-conventional water resources to address the increased demand in clean freshwater. Therefore, the application of treated wastewater for horticultural and agricultural irrigation has much potential for plant production. Among the current treatment technologies applied in urban wastewater reuse for irrigation, wetlands are evaluated to be the one of the most suitable ones in terms of pollutant removal, lower maintenance costs and energy requirement.
in terms of pollutant removal, lower maintenance costs and energy requirement.
Wastewater treatment efficiency of the constructed wetland depends on their macrophyte composition, substrate, hydrology, surface loading rate, influent feeding mode, microorganism availability, and temperature. Most of the centralized wastewater treatment systems in Pakistan are non-functional, whereas, untreated wastewater is causing environmental and public health hazards. Thus, following the Pakistan’s National Water Policy to address water scarcity and quality challenges, PCRWR has developed a model of constructed wetlands to demonstrate 3R principles (Reduce, Recycle and Reuse), ensure environmental friendly water conservation, water quality improvement and biomass production. PCRWR wetlands constructed on area of 700 sq.ft and as nature based solution was aimed to provide ecosystem services reusing treated water for horticulture/agriculture; contribute in maintaining a healthy environment and provide a recreational site.
How Wastewater is treated?
The wastewater from three building blocks of PCRWR is transported to the hybrid constructed wetlands, where it flows across layers of media and roots of submerged plants which adsorb the contaminants and reduce the pollution level in compliance to the National Environmental Quality Standards of Pakistan. This treated water is used for lawn and horticultural irrigation (using sprinkler and drip irrigation) and land flushing.
Impacts on Eco-Hydrology
PCRWR constructed wetland approach is evaluated and found to be very effective in removing organics, nitrogen and suspended solids as evident from PCRWR laboratory findings.
Waste to Green Opportunity
A good dual interaction between treated wastewater and biomass production is developed (fruits & a nursery) which is reducing hazardous impacts on the ecosystems. As a result a recreational site is developed to reuse treated water to enhance aquatic resilience and has regulated pollutants and nutrient dynamics in PCRWR catchment.