Researchers paint bleak picture of future water supply

January 28, 2007

Driving through the Okanagan Valley during the spring or summer is breathtaking. The rippling lake gleams against the backdrop of the mountains. Streams are rushing, as deer come down to get a drink. Orchards and vineyards are blossoming and fruit is starting to fill the branches. The sprinklers in large fields glisten in the sunlight. In neighbourhoods, manicured green lawns and bright gardens bloom.

Fast forward 50 or 80 years and the picture will likely be much bleaker. The lake levels will be much lower and beaches much larger. Where streams once ran, there will be only stones. The fish and wildlife that once fed from these areas will be gone. The temperature will be several degrees hotter. The fruit that once grew on the vine in June, will blossom months earlier and stay there for much longer. Wells will have run dry. The desert in which we live now, will take on its true form.

But a large group of scientists are working to change this scenario. About 100 researchers, scientists, planners and policy-makers gathered at the Penticton Lakeside resort this week to discuss the future of groundwater in the valley.

While groundwater was the focus of the symposium, the central message was that all water is connected in the Okanagan Valley and its supply is finite.

The Groundwater Assessment of Okanagan Basin — a joint initiative between several university scientists, the Ministry of Environment and the Geological Survey of Canada of Natural Resources Canada — has been assessing groundwater in the Okanagan Valley for the last three years. The group’s aim is to determine how much is there — which has yet to be determined — how it can be managed and how much is needed in the future.

The study in the Okanagan has been undertaken because of the valley’s arid climate and rapid growth over the last 30 years.

In 1971, the population of the Okanagan Valley was 115,000. By 2001, that number grew 175 per cent to 317,000 people. By 2031, researchers predict that number will exceed half a million people.
 
It’s not just urban growth that’s occurring, said Dr. Diana Allen, a hydrogeologist at Simon Fraser University, one of the project leaders for GAOB, which is funded by the Canadian Water Network.
 
In 1971, there were fewer than 12 wineries in the Okanagan Valley, now there are 82. Ski resorts have doubled and golf courses have gone up 600 per cent.

As a result, Allen said demand on water systems has rapidly increased. Okanagan residents are some of the biggest users of water in the entire world. In Canada alone, the average household uses about 350 litres of water per day. But domestic users in the Okanagan — excluding agricultural users — use between 450 and 600 litres of water per day.

Carolyn Stewart, Penticton’s water conservation program co-ordinator said many people do not realize that our abuse of water is far reaching. All of the water systems are connected, she said.
 
When we take water from a well, we’re taking from streams and lakes too.
 
“When you take away from one, you take away from the other,” she said.
 
The cycle of water

All water that comes into the valley comes out of the sky, either in the form of snow or rain. Before it lands, however, 85 per cent of the water evaporates and only 15 per cent actually lands or is absorbed into the soil.
 
The snow pack that accumulates during the winter on Okanagan mountains, melts in the spring and either moves into lakes via streams or it moves underground, feeding aquifers and, years later, feeds into the lake.

Because of the size and number of Okanagan lakes, which stretch from one end of the valley to the other, there is a myth of abundance.

“It seems counter-intiutive to say there is a water shortage,” said Bob Turner, a research scientist with the Geological Survey of Canada who created a poster about the Okanagan Basin waterscape.
 
“(But) there is a finite amount of water in the Okanagan.”

Only the top one-and-a-half metres of the lake are replenished every year — scientists estimate the lake water cycle is similar to a human life cycle.
 
Of the water that is pumped out of the lakes or from the ground for residential use, only 70-80 per cent is returned as treated waste water. In agriculture very little of the water is returned — the majority is absorbed by plants and eventually evaporates.

Water systems in the Okanagan draw from two sources, either groundwater or surface water.
 
The Okanagan’s issue will be the capacity to store water as more and more people take from the system.

Although the groundwater eventually feeds the lakes and streams, the lakes and streams will not feed the groundwater — the lakes are in the valley bottoms and gravity eventually pulls all of the water into those sources.
Water therefore must be managed correctly to ensure that as growth continues to occur in the valley, the water sources aren’t tapped out.
 
Turner’s poster says that the water system operates like a bank account: if Okanagan residents are withdrawing more money than they are putting in, then they will eventually run out of money.

“Water use will become a serious issue in the future,” said Turner. “It is already an issue and will become more of an issue.”

Climate Change

Studies in the Okanagan have shown that we are already using too much water, but climate change will only exacerbate the loss.

“The projections of climate change are very disconcerting,” said Turner.
 
According to environmental studies, the temperature will increase up to four degrees by 2080, which will result in an increased growing days for agriculture.

This means that growing seasons are going to get much longer. The current growing season is 167 days and by 2080 it will stretch to 216 days. While this will be good for growers, it will mean there is more demand for water, said Allen. A smaller snow pack due to the warmer conditions will also mean that it will be drier earlier in the year. Hotter weather will also increase the level of precipitation that is evaporated. The lakes, streams and groundwater will have less recharge.

“Climate change creates huge uncertainty,” said Turner. “It definitely gives pause in terms of growth.”

Planning for the future

People have to make changes now, said Turner.

“There is a lot of room for improvement because we have become so wasteful,” he said, adding a good first step is relegating green grass to the history books.
 
Xeriscaping yards is one step that residents can take — this means using natural plants that are suited to the arid environment of the Okanagan and require little water. Residents should also change the way they use water in their home by installing water-efficient appliances.
 
While every person can make a little difference, the major changes will have to come from government.
“Municipalities have to look at growth and whether it is sustainable and whether the water resource is sufficient,” said Turner.

This means incorporating the scientific research into municipal decision-making.
 
The Regional District of Okanagan Similkameen is already using this connection as part of the 20-year regional growth strategy.

Water has already become the top directive for determining the extent of future growth and where it will happen, said David Arsenault, regional growth strategy co-ordinator.

The Okanagan and Similkameen valleys will be growing at between one and two per cent and the regional growth strategy is planning to ensure that growth is focussed in the existing urban areas. Arsenault said they want to keep growth out of the rural areas and densify the urban areas, where supporting infrastructure is already in place. This will thereby ensure that water has large porous land on which to fall, rather than landing on concrete roads or rooftops.
 
As part of the strategy the RDOS, with help from Natural Resources Canada, is creating a modelling tool that will show future growth in the community based on land allocation. The modelling will take the footprint of the community to create a three dimensional image of the community in the future.

Taking these forward-looking steps will help to ensure the valley doesn’t “hit the wall” and run out of water, said Turner.

For many people it is hard to think about the magnitude of our current actions and how much the actions we take today affect the outcomes of tomorrow, he said. But with promotion and education — through public awareness tools like the Okanagan Basin Waterscape poster — people will get the message, agreed Allen.

“Love our water, and be careful when you use it,” she said.

Anyone who would like a copy of the poster can pick one up at Penticton Public Library or at Penticton’s Ministry of Environment office.

These diagrams from the Okanagan Waterscape poster indicate some of the ways homeowners can reduce and manage water consumption. Carolyn Stewart (front page) is responsible for ensuring that these messages of reduced consumption are heard by the public and local government.