How Efficient Would Demand-Based Water Strategies Be for Qatar?

Abstract

Qatar is a water scarce country that heavily relies on seawater desalination. Multiple studies have concluded the need for a more resilient water planning through efficient "demand control" strategies. This study is among the very few attempts to "quantify" the actual impact of such solutions on the water sector. The purpose of this work is to generate "indicative" water usage figures to inform the (non-technical) decision makers and prove the benefits of shifting toward demand-based water strategies. A scenario-based approach was adopted, considering: maintaining status quo (scenario 1), improving the water pricing system (scenario 2), and regulating greywater reuse (scenario 3). Scenario 2 estimates the impact of water tariff increase based on Price Elasticity of Demand in neighbouring countries. Scenario 3 considers imposing on-site greywater reuse as part of the permitting process (for new constructions only). The study forecasted, up to year 2100, the impacts of demand control measures on: (1) domestic water consumption, (2) volume of desalinated water, (3) year by which additional desalination capacity is needed, and (4) year by which wastewater treatment facilities need expansion. It was shown that, by improving the water tariff system, the total domestic water consumption is reduced by up to 27% (equivalent to 16-19% reduction in total demand for desalinated water). As a result, the need to expand the water desalination facilities and the wastewater treatment infrastructure is delayed substantially: 15-20 years and 15-30 years, respectively. Also, regulating greywater reuse may reduce domestic water consumption by up to 6%.