UBC Theses and Dissertations

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UBC Theses and Dissertations

Modelling urban development trends and outdoor residential water demand in the Okanagan Basin, British Columbia Maurer, Nathalie


The Okanagan Basin, the most arid watershed in Canada per capita, has been undergoing rapid population growth in the past 30 years. The results of this research show the varying residential water demand in the major communities in the Okanagan Basin. The outdoor water use was determined on a lot size basis for 2006 and projections were made to the year 2026 using a projected population increase and three urban development scenarios. The outdoor residential water demand varied from 30% to 60% of the annual domestic water demand depending on lot size. Two extreme urban growth cases: urban sprawl and densification, and an in-between scenario were developed using GIS for four case study communities: Vernon, Kelowna, Penticton and Osoyoos, which represent the diversity in climate and population trends in the Basin. The results showed that currently 47% of the domestic water is used for outdoor watering for the case studies. The business as usual growth scenario (urban sprawl), includes climate change and results in 7.3 Mm3 of additional water needed for outdoor residential water demand, a 55% increase from existing conditions. However, with densification, 5.7 Mm3 of outdoor residential water savings can be made. Additional water savings can be made if the existing outdoor residential water demand is reduced through more aggressive conservation practices such as effective marketing, reduced grassed area through xeriscape and mandatory watering restrictions. Using current growth projection to 2026 it is possible to significantly reduce outdoor residential water demand by more than 50% from existing conditions if densification and aggressive conservation practices are put in place. The methods and results of this research have been incorporated into the Okanagan Basin Water Supply and Demand Project, which is in the final phases of completion.

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Attribution-NonCommercial-NoDerivatives 4.0 International