WET Hydrology & Hydrogeology

CRD conducts research to support water efficiency programs. These resources enable residents and businesses to access the best advice from local and international experts in water efficiency and conservation. The CRD monitors water use trends in Greater Victoria and participates in product and technology research in partnership with other utilities. This research is used to ensure that our conservation programs provide excellent value to the community.

THE Capital Regional District, like many other jurisdictions in Canada, is facing drought and increasing competition for access to water. This presentation provides information on a water conservation project undertaken in the early part of this century.

Climate change and varying rainfall patterns are forcing municipalities in semi-arid regions such as the Okanagan to investigate more resilient ways to retain and use stormwater. With this in mind, a team of UBC Okanagan researchers used the campus itself to examine and evaluate the lifecycle of low-impact developments (LIDs) that are intentionally created to help control and retain rainwater.

The issue of water scarcity has been discussed for a long time, and there are many possible solutions offered by scholars and scientists, one of which is rainwater harvesting. Collected rainwater could be a useful water resource for non-potable water needs, instead of treated water. It could be used directly on-site, and it could reduce the cost of supplying water since it doesn’t need to be treated. Conventional rainwater harvesting is
collecting rainwater by existing surfaces without knowing if those surfaces are enough for needed water. As a result, the collected rainwater could exceed or be deficient for the need. This paper developed a framework to determine the size of impervious surfaces needed for a certain water use allocation. It also helps to estimate the right budget for collecting a certain amount of water. The UBC Farm located at the University
of British Columbia, Vancouver campus, served as the case study. Based on the irrigation need of UBC farm, a model was developed to calculate how large an impervious surface is required. The model has the potential to be adapted for other applications that do not require potable water. The benefits and disadvantages of rainwater harvesting were assessed and although there are disadvantages, the advantages of rainwater harvesting are greater than the disadvantages. Thus, rainwater harvesting is a valuable tool which can be used to alleviate water scarcity and reduce the cost of unnecessary centralized water treatment.

The Residential Rainwater Harvesting Design and Installation Guidebook has been produced by the Regional District of Nanaimo (RDN) to encourage the responsible use of rainwater as a safe, sustainable water source for private residences. It has been developed to inform and assist interested homeowners (as well as professionals such as engineers, designers, plumbers, and builders) about methods to capture rainwater as an alternate water source for potable and non-potable use. This Guidebook addresses best practices and is a guide for design, installation and maintenance of residential rainwater harvesting (RWH) systems. The 2007 RDN Drinking Water and Watershed Protection Plan and the subsequent RDN Watershed Snapshot Report 2010 emphasize the need for promotion of rainwater harvesting within the region, citing increased population, dropping groundwater levels in certain areas, and stressed ecosystems as reasons for the urgency. Many areas within the RDN are characterized by rock and soil conditions that possess limited ability to store surface and groundwater, while the climate follows an annual cycle of rainy winters and long periods of summer drought. By harvesting and storing the rain that falls during wet winters (when up to 80 per cent of rainwater runs off to the ocean), we reduce the volume of groundwater drawn from aquifers during dry summer months. By maintaining higher groundwater levels, we help to sustain a critical base flow in streams, and therefore protect fish and aquatic health. Reduced groundwater extraction also helps to prevent saltwater intrusion in wells located in coastal areas.