Water, water everywhere... It is a common perception that B.C. has an abundance of water and rain.
Drought is a recurrent feature of climate involving a deficiency of percipitation over an extended period of time, resulting in a water shortage.
On the mainland drought can affect the growth of agricultural crops and limit the amount of water available for irrigation. Low stream flows and little rain impacts the groundwater level. Lower stream flows can also cause warmer river temperatures which impacts fish and marine life.
On the Gulf Islands, drought season coincides with the summer tourist season and the associated increase on the demand for water. Reduced water availability during the summer can have a significant impact on the aquifers as there may not be enough water to allow for the refilling of them.
Gabriola Island is approximately 53 square kilometres of low altitude terrain. Overall, precipitation is low because it lies in the rain shadow of Vancouver Island and it's mountain ranges. Our ecosystem is unique. The aquifer system is complex and delicate. Our groundwater is derived solely from rainwater. The ground water is stored in small aquifers in the shale or sandstone in the ground solely by rain. The only real natural water storage is underground in the cracks, fractures and open spaces in the rocks. There are no other large deposits of water-bearing sand or gravel as there are in other aquifers on this continent. Winter snow is seldom seen here. There are no rivers and there are just a few small ponds/swamps/dugouts which are filled with the excess runoff in the rainy season from October to March. The soil is rarely thick enough to retain significant amounts of groundwater.
As precipitation declines in the summer months, the water tables become lower, resulting in wells being intruded by saltwater or drying up.
Being prepared to respond to droughts when they occur will help protect our water in the future. Managing and preparing for future drought is needed as there can be a decrease in our available potable water. If our ground wells are used too much it could result in a change of water quality as salt water intrusion into the coastal aquifers is possible.
The BC government is providing incentives to be water efficient by giving grants for the purchase of tanks for rain harvesting. We will need new approaches to water management as climate changes and continues to impact our water and aquatic ecosystems.
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