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Water Resource Management

Water Resource Management. Major Topics for this Week Nature and significance of water security at national and local scales The role of water allocation systems in minimizing conflict over use of water resources

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Water Resource Management

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  1. Water Resource Management Major Topics for this Week • Nature and significance of water security at national and local scales • The role of water allocation systems in minimizing conflict over use of water resources • The role of multiple levels of government, and of governance, in addressing local water quality problems • Resolving disputes related to water quality and quantity • Challenges over water governance

  2. What is Water Security? • Means different things .. usually refers to threats to water use from overuse and contamination • Global Water Partnership 2000 definition: Water security means access to adequate quantities of water, of acceptable quality, for human and environmental uses • Involves issues of scale (global, international, national, regional, local), types of water uses, threats to wateravailability, transboundary conflict and uncertainty and variability in supply

  3. Canada’s Water Resource Base • Immense and variable, like the size and diversity of Canada’s physical landscape • 600 mm (millimeters) annually in precipitation • 330 mm of this runs into rivers, streams, wetlands and groundwater = 105,000 cubic meters per second of discharge (which is 7 per cent of Earth’s total renewable water resource) • About 24 per cent of Canada’s land area is covered in freshwater • Canada has one-fifth (20 per cent) of the Earth’s total freshwater supply • So, we’ve got lots of water and we never have to worry about water security, right? …

  4. Myth of Canadian Freshwater Abundance • The numbers are deceiving, leading us to believe Canada has plenty of water to spare • For example, only a tiny portion of the vast water supply of the Great Lakes—approximately 1 per cent—is renewed on an annual basis, the rest is left over from glaciation • Further, aggregate runoff and annual average data mask important spatial and temporal variability in water supplies: • 3500 mm of annual precipitation on Pacific coast • Only 500 mm on Prairies and in North) • Water is threatened by a wide range of human stresses such as overuse, pollution, and climate change

  5. Water Use Distinguish between in-stream, withdrawal and consumption uses of water Canadians use 329 litres per day (among the highest in the world) Water intake varies across regions and by sector:

  6. Water Abuse • Which is point source and which is non-point source? • Municipal sewage • Phosphorous in agricultural runoff • Industrial discharges, heavy metals and PCBs • Nitrogen from fertilizers and pesticides • Water-born diseases can be eliminated through modern water treatments techniques… Yet, deadly outbreaks still occur (like Walkerton (Ont.) in 2000; boil-water advisories are common) • Leaky underground storage tanks, chemical spills, and land use practices, impacts from intensive livestock operations • Climate change impacts on water quantity and quality…

  7. Water Allocation Deciding who get to use scarce water resources has been a challenge for millennia But now, with population growth, industrialization, climate change and the need to protect ecosystem functions—the challenges are even greater Unfortunately, many water allocation systems were established during a time when demands were less severe than, or quite different from, what they are now. Updating those systems to reflect modern circumstances and needs can be challenging Allocation laws within jurisdictions vs between jurisdictions

  8. Water & the Canada–US Border • 8,900kmCanada–US border,numeroussharedwaterbodies • Boundary Waters Treaty (1909) began with the Milk River allocation conflict, established the International Joint Commission (IJC) to investigate boundary waters issues • In 2005, Ontario, Quebec and 8 Great Lakes states sign an agreement to protect and conserve the waters of the GL basin • NAFTA agreement and bulk water exports: contentious issue? • Is water a tradable good (like automobiles and lumber)? • Bottled water is a tradable good, and what about water in its natural state? (NAFTA is not clear on this topic) • In 2000, IJC deemed NAFTA cannot force Canada to allow bulk water exports • In 2001 an act to amend the BWT was passed (in Canada)

  9. What about International Trade in ‘Virtual’ Water? • Refers to the volume of water required to produce a commodity—that is, the water ‘embedded’ in the commodity. Examples: • 200 millilitres of milk has a virtual water content of 200 litres (How so?) • Cotton T-shirts contain 2000 litres of virtual water • Estimated international virtual water flows from 1997 to 2001 were 1,625 billion m3/year (Chapagain and Hoekstra 2008) • In the context of limited water resources, uncertainty around climate change impact, and intense competition for water, ‘virtual water exports’ in livestock exports using water-intensive irrigated feed may become a concern in future

  10. Water Quality Management • Water quality is a function of physical, chemical and biological properties • Water quality is naturally variable, and human impacts are significant, measurable, preventable • What is ‘good’ water quality? Depends on the intended use, and acceptable level of risk to humans and aquatic systems • Boatable • Swimmable • Drinkable • Management of water quality involves all levels of government (national, provincial, municipal): complex & piecemeal laws across several jurisdictions

  11. Toward Water Security • Integration is essential… water management is integratedwhen important links and relationships are acknowledged in the decisions that resource managers make about water • How surface and groundwater interact • How land and water interact • Maintaining purity of water, rather than only focusing on cleaning it • Governance matters… Governance refers to the processes by which societies make decisions—in this case, decisions about water (laws, policies, organizations, citizen actions, etc.) • E.g. Bi-national Great Lakes Water Quality Management • Long history of agreements • 360 chemicals (11 critical toxicants) found in Great Lakes • Refining ecosystem approach, pathways, aquatic health

  12. Columbia River Treaty (Revisited) • Originally signed by Canada and USA in 1964 • Provided for building a number of dams for power and flood control • Treaty can be terminated as of 2024 with 10 yrs advance notice • Options for management are: • Continue the Treaty with the automatic change to “called upon” flood control • Terminate the treaty, or • Negotiate changes to the treaty that modify flood control and power obligations and/or create new provisions for other benefits, especially environmental objectives. • Final result ???

  13. Owen’s Valley, California William Mulholland Chief, LA water department

  14. Problems: unsustainable use of groundwater • Shortfalls in water often made up by tapping fossil water • Usually free to anyone who can afford to sink a borehole • Used copiously for irrigation in areas otherwise not suitable for crop production • Often extraction is subsidised by low cost energy for pumping, credits for installing wells • Water level drops if rate of extraction exceeds recharge • Major problem in Punjab (India), Northern China, USA (Ogallala Aquifer), Australia, Middle East

  15. Ogallala Aquifer WYOMING SOUTH DAKOTA • Aquifer formed around 20 million years ago • Most of the water is fossil water – some is millions of years old • Irrigates 20% of all US cropland • Total drawdown around 30 km3/year • Recharge is negligible (0 – 150mm/year) • Falling at 2 metres per year • Many wells expected to dry up or be uneconomic to pump by 2050 NEBRASKA KANSAS COLORADO OKLAHOMA NEW MEXICO TEXAS Kilometers Less than 61 meters (200 ft) 0 160 61-183 meters (200-600 ft) More than 183 meters (600 ft)

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