Re-setting the Water Supply and Demand Relationship
Water scarcity events – when demand for water is greater than supply – typically occur in B.C. during late summer and early fall. Such events are becoming more common due to increasing human use of water, greater recognition of ecosystem needs, and changes in water supply linked to climate change. Everyone can help prepare for water scarcity, and contribute to watershed security, by reducing water demand and, in some cases, by increasing water supply.
Water Demand Management
Most people in B.C. receive water from a water utility or local water provider. For example, in Prince George, the City supplies, pumps, treats, stores, and distributes an average of 189 million litres of water to residents every day. This water is supplied from 15 reservoirs and 6 wells via a network of more than 550 kilometres of distribution pipes.
These local water providers must have a licence that authorizes them to divert and use a specified amount of water from a stream or aquifer. Some water providers encourage residents to install low flow toilets and shower heads, use drought resistant plants in landscaping, or use water at off-peak times. Water providers can also reduce water loss by fixing leaks throughout the water distribution system.
Many rural residents and businesses obtain their water directly from a stream or aquifer. These persons must also have a water licence unless they use water only for household use.
Different water users will manage demand differently based on their specific needs. Agricultural producers can invest in efficient irrigation systems, build up soil, or switch to drought-resistant crops. Industries can invest in production systems that use less water or reuse the same water in closed loop systems.
Although the Province encourages voluntary water conservation through infrastructure grant programs, policies, guidance, and tools, British Columbians could do much more to reduce their water use.
Water Supply Enhancement
The main options for increasing water supply are storage and re-use. Water storage can be applied at various scales, ranging from individual household storage tanks, to on-farm dugouts, to reservoirs serving a larger region. In many parts of B.C. it is possible to capture winter rainfall and/or some of the water released during the spring freshet and store it for later use.
In some locations it may be possible to divert and store urban stormwater runoff in aquifers and to use this water for irrigation and other purposes following appropriate treatment. Some coastal cities may be able to supplement their freshwater supply by using seawater for toilet flushing and cooling functions. Additionally, while treated wastewater is not widely used in B.C., the Province has guidance on the use of reclaimed water for specified uses. These and other water supply enhancement options are used in many parts of the world and may become increasingly important in B.C.