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Hydrology and Water Resources



Water Availability / Hydrology and Adaptations to Climate Change

“The variability and the uncertainty that variability provides are perhaps the most difficult environmental properties for managers, planners and policy-makers to deal with effectively.”  The Water Quality Board of the IJC.

Evidence collected over the last ten years has increased the confidence of scientists that climate change and its related impacts are real concerns.  Many stresses already challenge the Great Lakes, such as changes in land use, chemical pollution, overuse of fertilizers, alien invasive species, and acid precipitation.  The stress of climate change complicates and acts together with other stresses.

We depend on a clean, abundant water supply for human use; food, energy and industrial production; transportation and recreation; and the maintenance of natural ecosystems. It is estimated that water’s measurable contribution to the Canadian economy is from $7.5 billion to 23 billion per year.

Great Lakes Basin impacts for which adaptation and mitigation measures should begin:

  • Possible precipitation increases along with increased evaporation. This leads to reduced runoff and declines in lake levels.
  • Decreased lake-ice extent, including some years without ice cover.
  • Ecological impacts, increased water loss through evaporation and impacts on navigation.
  • Impacts on hydroelectric generation, shoreline infrastructure, shipping, recreation, use of toxic chemicals should have planned adaptations

The extent of changes in our climate, both present and projected, raises these questions:

  • What will be the extent of their impact?
  • Do we have the ability to adapt in the Great Lakes region?

Adaptation to less available water will involve changing the design and the approaches to water and energy systems. For example, metered water for all, well/ground water rights, water markets, greater efficiency and BIG STRAWS or water pipelines shared with communities along the route such as Georgian Bay to Alliston.

Ontario in 2005 has some of lowest prices in the world for supplying and treating water. But Ontario is lagging behind in upgrades needed in the present system.

Demand management and realistic pricing may bring about metering sooner. 26% of municipalities reported shortages of water due to increased consumption, drought, and infrastructure problems between 1994-99. Metered, flat rate households use 50% more water.

Water demand may outrun supply in many areas of the province. Available water supply will be reduced due to more surface evaporation and less groundwater recharge. At the same time, an increasing Ontario population will demand more water. There may be a reduction in the water supply even if there is an increase in precipitation.

Research in one area showed that a 16% reduction in stream flow even though the precipitation had increased by 33%!

Extreme events such as flooding leave behind ideal growing conditions for molds in buildings – homes, commercial and industrial complexes.

Municipalities may have to allow a sewage mix with excess runoff to lakes. Floodwater’s’ may back up sewage lines as happened in Peterborough July 2004 leaving millions of dollars of damage.

Lower water levels may result in more boil water notices, since any spills will have a greater concentration of pollutants. Some pollution is measured in parts per million or mpm.

Adaptations for lower water levels will involve consideration of many sectors. See the diagram below.

Source: Natural Resources, Canada, 2003

1. Choose one impact and develop a list of adaptation measures that should be taken.
2. Research this choice in your area.

Adaptation to climate change means that a conservation culture by individuals, business, and industry will be needed. The need for greater efficiency /conservation of water will lead to water-efficient appliances, recycling water, grey water usage. Realistic user fees may be necessary. Choices will have to be made to reduce the usage of water and increase the expense involved in providing drinking water and treating waste-water and sewage.

Biosystem approaches and artificial wetlands benefits will become important. Vulnerable wetlands and aquifers will be threatened, fjor example, ground water reservoirs in the marginal land in Eastern Ontario.

Sports and recreational facilities and their support systems will have to adjust. Lengths of seasons for recreational activities will change as periods of warmer weather grow longer and winters become shorter, even milder. For example, shifts in use from snowmobiles to watercraft and from snowboarding to skateboarding. Recreational boating may be vulnerable with lower water levels.

Swimming and other water contact recreation may have to be limited due to bacterial outbreaks such as E. coli. Water quality maybe affected by algal blooms. Waste water/sewage treatment locations will have to considered for risk during major thawing or heavy rain events.

Present research shows that the Great Lakes levels respond to climate variability and the levels will be hitting record lows more often as water levels decline. Great Lakes water levels may be lower by one to two meters, causing loss of wetlands. Loss of this habitat will affect fish and migrating waterfowl populations. Shallower rivers and streams, especially if unshaded, will warm more quickly.

Lowering of water levels in lakes impacts the natural aquatic world, bringing about shoreline and wetland changes, species changes, and changes in pollution concentration. These changes in turn may cause an increase in the degree of tainting of odor and flavor of water, and remaining species of fish and wildlife.

Beaches may grow bigger as more shoreline appears. Management of this emerging shoreline with more exposed docks will be needed. Present shorelines hardened with Gabian baskets, retaining walls, etc. will have to be addressed as they are left behind.

In the future, it will be harder to protect water quality and supply and deal with the conflict of uses, for example ground water supply for farms vs. municipalities vs. industries.

Water considerations for economic activity might include considerations of:

  • Hydroelectric power generation and transmission
  • Commercial navigation
  • Industry – new technologies
  • Urban development and infrastructure
  • Recreation and tourism
  • Agriculture

The challenge of climate change also provides new opportunities for innovative solutions such as redesigning appliances, retrofitting present installations and better investments. For example, Toronto Condo Owners Going Green Retrofit returned 5% on investment in their own building in 2004.

Designated growth areas, natural heritage systems, greenbelts, brown and grey field sites can plan integrated infrastructure, that is an integrated network for transportation, sewers and H2O. This is such a major undertaking that, in 2003, the newly elected Ontario government created the Ministry of Infrastructure.

Canal and harbor dredging, use of the St.Lawrence Seaway vs. the Churchill route through Hudson’s Bay may have to be considered. The return to the historical canal and lake vessels from Montreal then Prescott to the Great Lake-head might even warrant consideration when cargo vessels are limited to smaller drafts due to lower water levels.

See the diagram below considering the risk of lower water levels due to climate change in future planning.

Source: International Joint Commission (IJC) Climate Change and Water Quality in the Great Lakes Region. May2003 www.ijc.org

The Bay of Quinte data from 1971-1992 is used below as the base line to model the climate change scenario for 2030, 2050, 2090. The rate of evapotranspiration will increase with warmer temperatures. Also, the bigger the surface area, the more water will evaporate.

ACTIVITY 2 Locate the Bay of Quinte on a map of Ontario.
1. Describe general pattern predicted.
2. How does this pattern relate to the average?
3. What does the y axis predict for all 3 scenarios?

ACTIVITY 3 Research
1. How does the area of the Bay of Quinte compare with Georgian Bay?
2. Find the graph that tracks the monthly means in water levels over 70 years in Lake Huron on this website. Note: Low levels of lake water follow the driest terrestrial years.

The graph below shows the number of days of rain and days with snow for one weather station. Data from 1961-1990 from the Windsor station is used for modeling the years 2040-2069 to show the shift in seasonal forms of precipitation impacted by climate change in the Windsor area.

Which of these applies in your community?

ACTIVITY 5 Research
Choose any one adaptation for your community and research the steps needed to put this adaptation into action.

The graph below is a comparison of days with rain and days with snow for Windsor weather station for the current climate (1961-1990) and 2050 scenario climate from climate model CGCM1.

Source: Environment Canada

1. Locate Windsor on a map of Ontario.
2. Describe the overall shape of the graph and what this pattern means for the future.
3. What adaptations should the city of Windsor and the surrounding area begin to undertake now?

Even if there were greater precipitation each year, precipitation may not be as available in key seasons. Precipitation falling more as rain than as snow in extreme events may be more harmful than helpful, to both natural and built ecosystems. Seasonal changes in precipitation may mean increases in winter runoff and earlier spring melts or freshets leaving lower water levels in the summer and fall. When data from the Great Lakes Watershed from 1961-1990 is used to run climate change scenarios for 2050, the trend is towards less snow and more rain, perhaps as ice rain.

The change in precipitation predicted is because of reduced snow cover due to temperature increases. This change can also be modelled using the effects of changes in carbon dioxide concentration.

The first figure below shows the current carbon dioxide with current snow cover depth in centimeters modeled with real data as a base line. The second figure shows the current data of snow cover depth (cm) modeled to show the impact of the predicted doubled concentration of carbon dioxide.

Current snow cover depth (cm) using real data from 1983 to 1987 to model snow depth (cm) for actual depths and depths predicted for a climate with 2x C02 concentration.

1. What adaptations for these changes in snow cover should the municipalities in this area begin now?

ACTIVITY 8 Research
See the box below for possible barriers to community adaptation.

Adaptive capacity is the ability of a community to adapt and to cope with climate change impacts. The ability of a community to respond to climate change depends on its wealth, scientific and technical knowledge, information, skills, infrastructure, institutions, and equity. Attitudinal and behavioral change should not always have to be a personal response to an extreme weather disaster such as an ice storm.

Attitudes and behavioral change should come from the need to better the common good. Each person should understand that each personal conservation action can be multiplied by 10 million Ontarians or 30 million Canadians. Working together l can reduce or mitigate the impact of climate change.

Being aware of the present and future impacts of climate change gives communities a longer time to plan and to begin putting plans into action. Adaptive planning can reduce risk to damage from the effects of climate change. Monitoring, reporting, and planning for change are the beginning of important activities. Changing human behavior towards both the built and natural environments is the key to reducing the risks of damage due to climate change.