Hello.
Thank you for giving me the opportunity to speak to you today. I do so as a professor in the earth sciences department at UQAM, but also as president of the Quebec Groundwater Network, whose mission is to share knowledge on the science of groundwater.
Today, I'd like to make three observations about groundwater and suggest three courses of action.
First of all, groundwater is still a relatively unknown resource in Quebec and Canada, and elsewhere in the world. In recent years, however, significant progress has been made in this field. We are more knowledgeable about our resources, particularly in Quebec. I want to point out the investment that the Government of Quebec has made in groundwater mapping since 2009. It has done an exceptional job.
In Canada, groundwater is used for drinking water supply, industry, agriculture and ecosystems. We do not often talk about this, but it is very important. We know that the volumes are significant, but that they are renewed in sometimes very contrasting ways from one region to another, and they are not evenly distributed over the territory.
We also know that groundwater is subject to numerous pressures, such as increased pumping, urban sprawl, agricultural intensification and climate change. These pressures can lead to drops in groundwater levels, the drying up of watercourses and wetlands in summer, and a decline in groundwater quality. We are only just beginning to quantify these impacts and their effects on human uses of groundwater and on ecosystems.
Secondly, groundwater is generally closely connected to rivers, lakes and wetlands. These interactions are generally crucial, not least in sustaining natural environments by creating habitats for many species, but they are rarely taken into account. While it is important to protect the banks of a river or the immediate surroundings of a well, for example, this is often not enough to ensure the sustainability of the resource or habitat, as groundwater often comes from very far away. The areas where groundwater infiltrates—upstream of watersheds, in wetlands, in forest massifs—must also be protected to enable the renewal of the resource, the maintenance of groundwater levels, and the natural attenuation of pollutants.
We still understand relatively little about all these connections and the resulting feedback. There is no doubt, however, that integrated management on the scale of watersheds, for example, increases the resilience of all water resources.
Thirdly, groundwater flows very slowly and can remain underground for periods ranging from a few years to several thousand years. Groundwater pumped today may have infiltrated the soil a very long time ago, and the pressures imposed on these resources now may be felt by several generations. Groundwater has the particularity of being indirectly exposed to anthropogenic pressures and climatic hazards that occur at the surface. For this reason, impacts are often delayed in time. They may occur downstream of pressures and are sometimes difficult to measure in the short term. They may also take decades to subside.
Networks for monitoring groundwater levels and quality are still too sparse and too recent to afford a long-term vision of the resource. Despite all this, development and operating authorizations continue to be based on short-term planning, sometimes for only a few years, which limits our ability to ensure the sustainability of the resource.
These three observations lead us to reflect on the priority areas for groundwater protection.
First, we are not knowledgeable enough about groundwater. It is important to continue developing knowledge to describe the resource, to map it, to quantify current uses and to monitor groundwater quantity and quality.
Second, groundwater management must be integrated with surface water management. It must take account of all interactions and consider time scales ranging from a few years to several decades, or even several centuries.
Third, it is vital to mobilize groundwater knowledge as widely as possible. Groundwater is under our feet, so we don't see it, and it is not part of the general culture to know where it is and how it works. The objective is for all users to have access to new data and understand the issues surrounding the state of the resource and emerging problems.
In conclusion, Quebec and Canada have plenty of groundwater, but the resource is unevenly distributed over the territory and is under pressure in many places. A global vision and concrete actions are needed to maintain available volumes, preserve the quality of the resource and maintain ecosystems for generations to come.
Thank you.