The intensive cultivation of land within the ALR makes Metro Vancouver one of the most important agricultural areas in the province of British Columbia. The region’s productivity and profitability is dependent on access to water for irrigation.
Combined, climate variability, increasing competition for water at the urban fringe and increased dependence on irrigation have the potential to cause both increases in demand and reductions in water availability. However poor regulation and monitoring of groundwater and surface water use results in uncertainty regarding future water availability and presents risk for the future vitality of the agricultural sector.
Improving our understanding of the irrigation demand for agricultural production is a crucial step toward strategically managing the water resources upon which the agricultural industry depends. By using the AWDM as a comparative tool, total irrigation demand in the region can be estimated with respect to important factors including crop type, irrigation system and soil texture;
- Total irrigation demand in Metro Van for the selected crops and municipalities is estimated as 30M m^3 per year.
- The crops with relatively high irrigation demand include cranberries (4,576 m^3/ha) and forage (4,185 m^3/ha). Blueberries (2,403 m^3/ha) and vegetables (2,436 m^3/ha) have relatively low per hectare irrigation demand.
- In dry year for the overall region (2003), Metro Vancouver is estimated to require 30% more irrigation water relative to an average year (2010) and 65% more irrigation water relative to an overall wet year in the region (2003).
- There is potential to reduce vegetable irrigation demand by 24% by transitioning vegetables from travelling gun and sprinkler systems to drip irrigation systems. This represents an overall reduction in Metro Vancouver irrigation demand of 4.2%.
- A complete expansion of vegetable or blueberry crops into potentially irrigated ALR land is estimated to increase Metro Vancouver’s irrigation demand to 65M-86M m^3 per year, depending on selected irrigation system. In contrast, a complete conversion of potentially irrigated land in the ALR to forage is estimated to require a total irrigation demand of 120 M m^3.
Under the updated regulations of the Water Sustainability Act, water resource managers can facilitate the reservation of water for agriculture. However, before these policies are developed there is a need to improve our understanding of irrigation demand for agricultural production: An important step toward strategically managing the water resources upon which the agricultural industry depends and establishing security within the sector.
Photo credit: Flickr See-ming Lee