The basics of water supply.

The image above is taken from a mountain top, in northern Idaho, in December of 2005. We include this image because this location shows mountain top snow and the lake into which the water will flow.

The lake below is Lake Pend O'reille. The lake is quite large and you can see only a small percentage of it.

The lake is fed by the Clark Fork River and the Pack River, as well as numerous smaller streams, creeks and springs.

In comparison to most lakes, Lake Pend Oreille would be considered a very clean lake. Most of its shore line is undeveloped and all towns, on the lake, operate waste water treatment plants.

But...

Each year, the water in the lake diminishes in quality. The quality of water diminishes regardless of the fact that all required treatment of water entering the lake "meets government standards".

Ground Water

Ground water accumulates in the space between soil particles, rock or within the major cracks of bedrock. Major reservoirs of ground water are referred to as aquifers.

Ground water has been a primary resource, due primarily, to it's higher range of water quality and the reduced capital expenditure associated with providing water to remote locations.

The Occurrence of Ground Water

Approximately 97 percent of the world's fresh water (excluding polar ice caps) is ground water.

Aquifers occur in two types of geologic formations.

Consolidated formations
Consolidated formations are those composed of solid rock with ground water found in the cracks. The amount of ground water In a consolidated formation depends on how many cracks there are and the site of the cracks. For example, consolidated limestone formations often contain caverns with much water In them.
Unconsolidated formations
Unconsolidated formations are composed of sand and gravel, cobblestones, or loose soil material. The quantity of ground water in an unconsolidated formation varies depending upon the density of the solids within the formation. Sand, gravel and cobblestone formations are generally high-yield aquifers, whereas, fine grained materials typically possess low yields.

Percent of population dependent upon ground water, by State. (top 10)

Hawaii	93
Mississippi	93
Idaho	91
Florida	91
Nebraska	90
New Mexico	90
South Dakota	85
Iowa	81
Minnesota	80
Alaska	79
Wisconsin	70

Water Supply and Demand

The global water supply vs. demand balance is increasingly impacted by lack of supply, as well as increasing disregard for the protection of ground and surface water quality. This is due to population growth, particularly in arid, water short regions, contaminated water sources, and inefficient utilization of available supplies. New industrialized nations, such as China, India and even Vietnam have placed economic growth superior to protection of local water quality. Increasingly, futurists are predicting a world where water shortages could cause increased food imports, population shifts, domestic political unrest, and geopolitical conflict. As the potential for future crisis rises each year, calls to address water supply issues are becoming more urgent, though political action to change these trends has so far been muted.

Here are a few facts about water supply and use (gleaned primarily from the World Resources Institute, the United Nations Environment Program, the Center for Strategic and International Studies, and

Water supply is finite water is recirculated through the atmosphere, but no “new” water is being created

Only 3% of the earth’s total water supply is fresh water, versus salt water, and the majority of fresh water is inaccessible

1% in surface water, such as rivers, lakes, and streams

29% in underground aquifers, which are being over-pumped beyond their recharge capability in many regions

70% in frozen glaciers

15-35% of agricultural water withdrawals are in excess of sustainable limits

Water production lost due to leakage, theft, and inadequate billing practices is typically 40-50% in developing countries, and may be 10-30% in developed nations

Industrial withdrawals are expected to rise by 55% by 2025

Despite efforts by global governments, nearly 1.1 billion people still lack access to water supply service and 2.6 billion people lack access to sanitation, mostly in Asia and Africa

About 5 million people die every year from water-related illness

By 2050, untreated wastewater could contaminate one-third of global annual renewable freshwater supplies

The world’s population has tripled in the 20th century – but global water use has grown six-fold

Another 40-50% in population growth is expected within 50 years, along with increasing urbanization and industrialization, with the fastest growth taking place in water-short areas, including the American Southwest, China, and India

In 1995, over 400 million people lived in countries experiencing water stress
or water scarcity

By 2025, that number is expected to rise to 4 billion – over half the world’s
population 50% of global population growth is expected to take place in water-stressed countries

China’s demand for water is expected to increase 400% by 2030

China’s population is 21% of the world and is increasing 1%/yr, yet China only has 7% of the world’s water. 400 of China’s 660 main cities face water shortages one-third of rural residents drink unsafe water

By 2020, India’s demand for water is expected to exceed all current sources of supply

70% of irrigation and 80% of domestic water use comes from groundwater, which is rapidly being depleted. 15% of aquifers are in critical condition this is expected to grow to 60% in 25 years.

World Resources Institute
Map on Available Global Water Supplies

World Resources Institute. 2007. EarthTrends: Environmental Information. Available at http://earthtrends.wri.org. Washington DC: World Resources Institute

Areas with per capita water supplies below 1,700 m3 per year are considered under “water stress” below 1,000 m3 per year are under “severe water stress”

Assuming current consumption patterns continue, by 2025, at least 3.5 billion people will live in river basins under “water stress,” with 2.4 billion of them in “high water stress” areas – including the Colorado River basin in the U.S.

	WaterSupply.Com