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ACHIEVING ECO-NOMIC SECURITY*
ON SPACESHIP EARTH

By Jim Bell

CHAPTER IX

ECO-NOMIC SECURITY AND WATER

Water Problems

Increasing Water Security

Efficient Water Use In Agriculture

Strategies for Increasing Water Security

Appropriate Crops

Alice In Waterland Economics

Water Beefalow

Efficient Water Use In The Residential Sector

Water Recycling

Community Scale Water Recycling

Climate Appropriate Landscaping

Efficient Water Use In Industry

Efficient Water Use: Other Benefits

Protecting Watershed Function

Eco-nomic Watershed Use

Agriculture

Watershed Friendly Agricultural Practices

Watershed Function And Forestry

Forestry And True-Cost-Pricing

Land Development And Watershed Function

Protecting Watersheds from Pollution

Avoiding Pollution In And Around Our Homes

Weed Control

Watershed Pollution And Agriculture

Using Organic Agriculture To Avoid Watershed Pollution

Watershed Pollution From Business And Industry

Public Health And Toxic Waste

Some Good Efforts To Reduce the Production And Use Of Toxic Materials

The Economic Impact Of Environmental Protection

Efficiency and Renewable Energy: Developing A Watershed Friendly Energy Plan

Watershed Restoration

Re-establishing The Beaver

Groundwater Management

Protecting Groundwater From Pollution

Improving Water Infrastructure Security

Dams

Strategies For Reducing The Problem Of Siltation

The True-Cost Of Hydropower

Water Storage Problems

Improving The Eco-nomic Security Of Water Infrastructures

Quick Fixes Verses A Whole System Approach

 

 

 

 

 

 

 

 

Synopsis

Our water security, the availability of clean water in sufficient quantities to meet our needs, is decreasing. This decrease in our water security is caused by human activities which are contaminating our surface and groundwater. Human activities are also damaging the ability of our watersheds to recharge our groundwater systems.

All these problems can be corrected. And though it is not widely recognized, all the technological know-how needed to make these corrections already exists and is in use in various locations on our planet.

 

 

 

 

 

 
Water Problems
 

 

 

 

 

 

 

 

Until our sun burns out some 5 billion years from now, water on our planet is infinitely recyclable. Unlike oxygen which depends on plant life for renewal, the hydrological cycle needs only the evaporative energy of the sun to set it in motion. Changed into a gas through the absorption of solar energy, water vapor is transported by the wind throughout the atmosphere. Here it condenses as rain, fog, snow, or dew and returns to replenish the earth's land, waterways, and groundwater storage basins.

Even though the amount of water on our planet has not diminished, our water security (the availability of clean water in sufficient quantities to meet our needs) is certainly decreasing. This decrease in water security is primarily caused by human activities which are:

  • Causing the water on our planet to become increasingly polluted,
  • Reducing the effectiveness of our watersheds to store water and recharge groundwater storage areas; and
  • Extracting groundwater at rates that far exceed the rate of recharge. The United States, "as a whole uses 21 billion gallons a day (BGD) of groundwater in excess of local recharge rates." (389)

Although the present situation is becoming increasingly serious, there are a number of things we can do to reverse this trend.

 

 

 

 

 

 
Increasing Water Security
 

 

 

 

 

 

 

 

One way to increase water security is to use water more efficiently. By using water efficiently we reduce the drain on surface and groundwater supplies and the need to build or expand costly and ecologically damaging water storage and delivery systems. Efficient water use will also reduce the per capita cost of wastewater treatment. With more water efficient toilets and showerheads less sewage is generated per person.

Efficient water use does not mean doing without the productivity, usefulness, and enjoyment that the use of water can bring. It does not mean taking fewer or shorter showers or flushing toilets less often. It does mean using better technologies like low-flow showerheads and water efficient toilets.

Efficient water use also means that we can have luxuriant landscapes and productive agriculture by growing plants that are adaptable to local climates and by using water efficient irrigation technologies and strategies where irrigation is required.

Investing in water efficiency also makes good economic sense. The payback, or time needed to save enough money on reduced water purchases to pay for the cost of water saving equipment, is almost always less than 5 years and often less than two years. (390) These paybacks would be considerably shorter )if government subsidies which keep water prices artificially low were removed. If the true eco-nomic costs associated with damming rivers, building and maintaining aqueducts, depleting aquifers, using energy for pumping, and wastewater treatment were included in the accounting, the payback on saving water through efficiency would be close to instantaneous. (391) Just in the arena of energy, "California's vast State Water Project uses almost as much electricity to pump water around the state as all the people of Los Angeles use". (392)

California farmers that benefit from the federally subsidized Central Valley Project (CVP) "have repaid only 5 percent of the project's cost over the last 40 years, with the total subsidy exceeding $930 million." (393) Additional subsidies came in the form of "at least $200 million in water subsidies" that were given to farmers by the Bureau of Reclamation "in 1986 to grow crops that the Department of Agriculture was paying other farmers not to grow because of surpluses." (394)

Such subsidy-loaded policies have been resistant to change, and even when changes occur they tend to be incremental. Recently, the government raised one of its irrigation district water costs from $3.50 to $14.95 per acre foot when the district's contract came up for renewal. While this represents a 400 percent price increase, it is "still only 28 percent of the water's true cost." (395) Even this 28 percent figure is misleading since it only includes costs like building and maintaining dams and aqueducts and the cost of moving the water around. It does not include the ecological and social costs associated with our present water policies. If these costs were included in the analysis, the subsidies taxpayers are paying to keep the present systems going would loom even larger.

In all, "the government (taxpayers) is spending more than $534 million a year to provide cheap irrigation water to western farms, many of which in turn are producing surplus crops that reap additional federal farm subsidy payments, according to a new Interior Department report." (396)

 

 

 

 

 

 
Efficient Water Use In Agriculture
 

 

 

 

 

 

 

 

To maximize water security, it is important to use water efficiently in every way we can. But more efficient water use in agriculture could save more water than all other efficiency measures combined. Worldwide the amount of water used in agriculture "accounts for some 70% of global water use", greatly exceeding the quantity of water used for domestic and commercial purposes. (397) In countries like the U.S. that have well-developed irrigation infrastructures, up to eighty-five percent of all water used is consumed by agriculture. (398)

One of the most troubling aspects of this water use in agriculture is how rapidly it is depleting groundwater supplies. In 1986 the U.S. Department of Agriculture reported "that one-fourth of the 21 million hectares (52 million acres) of U.S. irrigated cropland was being watered by pulling down water tables anywhere from six inches to four feet per year." (399) The depletion of water tables because of crop irrigation is also a problem in countries like China and India. (400)

 

 

 

 

 

 
Strategies for Increasing Water Security
 

 

 

 

 

 

 

 

Whether in the United States or abroad, much of the water used by agriculture can be saved through the use of efficient irrigation practices and by growing climate appropriate crops.

The most prevalent form of irrigation in the world today is to periodically flood fields with water. This form of irrigation is inexpensive to establish where land is flat but it is not particularly efficient. (401) This is because a large percentage of water often runs off a field before it has time to soak into the soil. In poro)us soils substantial quantities of water can be lost because it percolates to underground levels beyond the reach of plant roots. (402) If this water returns to the aquifer from which it was extracted, this can be positive but not if the water becomes contaminated with pesticides and chemical fertilizers along the way.

Sprinkler systems are generally more water efficient than flooding because the amount of water applied and the evenness of its distribution is more easily regulated. (403) On the negative side, sprinkler systems are expensive to install and maintain. Sprinkler systems also increase the amount of water lost to evaporation. Water evaporation is increased as it is dispersed in small droplets through the air and as water sits on plant foliage. Such losses can be avoided to a large extent if sprinklers are used at night when the humidity is usually higher than it is during the day.

The efficiency of large sprinkler systems can also be enhanced by attaching "drop tubes" to sprinkler arms. "Called low-energy precision application (LEPA), these systems deliver water closer to the ground and in large droplets, cutting evaporation losses." (404) The efficiency of flooding and sprinkler systems can be improved if fields are precisely leveled. Laser technology can be used to guide farm equipment to insure accurate leveling. (405)

Drip irrigation, a technology developed in the 1960s in Israel, is a further advancement in the efficient use of water for growing plants. This method delivers water directly to each plant by means of small tubes that supply just enough water to saturate plant root zones. (406) Other drip technologies include soaker hoses and various specialized emitters suitable for different crops. Soaker hoses, for example, are good for many row crops because they weep water along their whole length. Drip irrigation devices can be used on the surface, on the surface below mulch, or below the surface depending on plant requirements. Losses to evaporation can be almost completely eliminated when emitters are installed below mulch or beneath the soil surface.

While drip equipment is relatively costly, increased crop yields coupled with money saved by reducing water consumption can result in a quick payback on the investment. In Israel, where drip systems are used to "supply water and fertilizer directly onto or below the soil...experiments in the Negev Desert have shown . . . yield increases of 80 percent over sprinkler systems." (407)

Computer technologies are also being mobilized to increase water use efficiency in agriculture. One devise called a tensiometer, measures the moisture content of the soil and the amount of moisture in the soil that is actually available to plants. (408) This second feature is important because some soils, like those with a high clay content, are so absorptive that they do not give up the water they hold easily to plants. Sandy soils, on they other hand, do not hold water like clay soils. They may have a relatively low moisture content but almost all the moisture in a sandy soil is available to plants. When tensiometers sense that the moisture content of a particular soil is too low to meet plant needs, they activate an automated irrigation system. Tensiometers can also be read manually for more low tech applications.

Automated irrigation systems can be programmed so that irrigation water is only applied at night to minimize the loss of irrigation water to evaporation. Automated systems can also be designed to detect leaks, compensate for wind speed, control the application of fertilizer, and optimize the effect of the fertilizer used. Though they are costly to install, such "systems typically pay for themselves within 3 to 5 years through water and energy savings (using less water means that less energy is needed for pumping) and higher crop yields." (409)

A new development in the efficient water use arsenal is to combine water efficient technologies with weather monitoring programs. The University of Nebraska's Institute of Agriculture and Natural Resources has developed a computer program called "IRRIGATE" that compiles information gathered across the state of Nebraska from small weather stations. By calling a telephone hot line, farmers can "find out the amount of water used by their crops the preceding week, and then adjust their scheduled irrigation dates accordingly." (410)

The California Department of Water Resources is involved in a similar program. The California Irrigation Management System (CIMIS) that is aiming to save 740 million cubic meters of water annually by the year 2010. (411) (740 million cubic meters equals a little more than 600,000 acre feet or about the same amount of water used in 1990 by the 2.4 million people living in San Diego County, California, USA.)

Like Nebraska and California, Wisconsin has developed its own system of weather monitoring to assist farmers. This system, which is called the Wisconsin Irrigation Scheduling Program (WISP), is managed by irrigation specialists through the University of Wisconsin. (412)

 

 

 

 

 

 
Appropriate Crops
 

 

 

 

 

 

 

 

Efficient water use in agriculture can also be improved by minimizing the practice of growing water intensive crops in climate zones that have little rainfall and high rates of evaporation. With water efficient cropping, the water requirements of a particular crop should be reasonably close to the natural precipitation that could be expected in the climate zone where it is grown. Irrigation for such crops would be relegated to evening out yearly rainfall totals and as a way to supply water during periods when rainfall is below normal.

To date, research in the development and use of low water use crops has been poorly funded. "Perhaps 15% of the $82-millon University of California budget for agricultural research is spent on water conservation, but mostly to improve existing crops." (413)

Nevertheless, there are a number of promising plants now being grown, some commercially and others experimentally. Sweet sorghum, for example, is already widely grown. It requires a third less water and half the fertilizer required by corn to produce a crop and sweet sorghum is an excellent animal food. Currently, most of the corn grown in the U.S. is used for animal feed. (414)

According to Steve Staffer, an alternative crop expert with the California Department of Agriculture, sweet sorghum can also outperform corn as an energy crop. An acre of corn can be processed into 360 gallons of ethanol. Processing an acre of sorghum can produce 600 gallons. Staffer estimates that by growing low water use plants like sorghum, "California could produce 25% to 30% of its energy needs, without affecting our price of food". (415) Given Staffer's projections, producing ethanol from sorghum alone could more than supply all the energy needed in California today if the efficiency measures described earlier were in place.

Other promising low water use crops include:

  • Canola, a seed bearing plant, which is used to produce "one of the healthiest cooking oils around and takes just a fraction of the water required by many other crops grown in the (Sacramento, California) region";
  • Buffalo gourd, a perennial that is native to the Mojave Desert, has seeds that can be processed into lubrication oil and a starchy root that can be used to make alcohol;
  • Guayule, a plant that yields rubber, kanaf, an African plant which can be used as food, clothing fiber, packing material, carpet backing, and as high quality newsprint that is so absorbent that the hands of newspaper readers stay clean; and
  • Tepary bean, a drought-tolerant high yield food crop that contains "as much or more protein than most edible legume crops." (416)

While the strategy discussed above may seem obvious, farmers who benefit from federal subsidies, which allow them to purchase water at rates as low as 1/10 the price that urban dwellers pay, have little incentive to grow things that make more sense in the desert. (417)

 

 

 

 

 

 
Alice In Waterland Economics
 

 

 

 

 

 

 

 

In his book Cadillac Desert, Marc Reisner points out such subsidies lead us into absurd situations. In 1986, four low value crops grown in California [pasture (grass and hay), alfalfa, cotton, and rice] consumed 5.3, 3.9, 3.0, and 2.0 million acre feet of water respectively. Added up, this is almost three times as much water as was consumed by the 27 million people living in California, including all the water they used to irrigate landscapes and keep their swimming pools full. (418)

Even if all these low value crops were totally discontinued and no more water efficient crops were grown in their place, the economic loss to the state would be $1.7 billion or less than one third of one percent of the $550 billion California economy. (419) "That $1.7 billion loss of revenue, by the way, is exactly the cost of the proposed Auburn Dam (in northern California) that farmers want taxpayers to build for them. By simply retiring the land we'd get 75 times more water for our money." (420)

Additionally, if we converted a little over half the land now used just to grow grass and hay to grapes or other speciality crops with a similar or greater dollar value, the $1.7 billion loss would be erased. (421) Grapes require roughly the same amount of water per acre as grass and hay pasture.

This is a perfect example of how the lack of true-cost-pricing promotes practices that are not in anyone's long term interest. This even includes the farmer whose over-irrigated soil is becoming increasingly unproductive as salt and other minerals are concentrated.

Another example of Alice in Waterland economics is the proposed Peripheral Canal (also in California). In his book Water and Power, Harry Dennis presents a well documented case that increasing water use efficiency will easily meet the water needs of California, into the foreseeable future, at a considerably lower cost both economically and to the environment. (422) If constructed, the 42 mile long Peripheral Canal and its associated projects would ultimately cost the public $23 billion or in excess of $100,000 per foot to build. (423) An essay by John Burnham, the Metropolitan Water District's only accountant until he retired, argues that even if water was delivered to Southern California by a completed Peripheral Canal, its $1,267 per acre foot cost would be over three times what people would actually pay for most uses. (424)

 

 

 

 

 

 
Water Beefalow
 

 

 

 

 

 

 

 

A parallel aspect of growing low water use crops is related to the production of meat. Currently, "Over half the total amount of water consumed in the United States goes to irrigate land growing feed for livestock." (425) To put this fact into perspective, a 50% reduction in the production of livestock nationally would free up almost twice as much water as is currently used in the U.S. domestically, commercially, and by industry combined. (426) Though the production of meat in all its forms is water intensive, growing beef requires the most water. It takes approximately 2,500 gallons of water to produce a pound of beef. (427)

Given this 2,500 gallon figure it takes up to 100 times more water to produce a pound of beef as it does to produce a pound of wheat. "Rice takes more water than any other grain, but even rice requires only a tenth as much water per pound of production as meat." (428)

 

 

 

 

 

 
Efficient Water Use In The Residential Sector
 

 

 

 

 

 

 

 

Although residential water use accounts for only about 8% of the water used in the United States, from an ecological security perspective it is important to use water more efficiently on every front. Using residential water more efficiently also makes good economic sense.

Even from the business as usual economic perspective a number of municipalities and agencies are getting on the efficiency bandwagon. For example, the city of Glendale Arizona passed an ordinance that gives residents up to a $100 cash rebate for installing low flow toilets (1.6 gallons or less). (429) This is because city leaders realized that rebating the toilets was much less expensive than increasing water supplies and sewer capacity. The California Department of Water Conservation estimates "that installing a low flow toilet can save a family of four $25 to $50 a year on water bills." (430) The producers of Consumer Reports magazine reported an even larger savings potential. "By our own calculations, an average family that uses municipal water can save as much as $50 to $75 per year on water and sewer bills by switching to low-flow showerheads and low-flush toilets." (431)

In addition to saving money on water, low flow shower heads and water efficient appliances also save on energy costs. Just changing from a 6 gallon per minute to a 2 gallon per minute showerhead can save over half the energy used in a home to heat water. (432) This can amount to an energy savings of $50 per year. (433)

Faucet restrictors, automatic shut off faucets, and water-efficient appliances can also save water and energy. Faucet flow restrictors and automatic shut-off faucets can cut the use of sink water in half while reducing energy consumption for water heating. State-of-the-art washers and dishwashers use only 70 to 75 percent of the water and energy consumed by less efficient models. (434) If all the efficiency measures just described were in general use, household water consumption in the U.S. could be reduced by 60% or more. (435)

The use of water in toilets can be eliminated entirely through the use of dry or composting toilets. Composting toilets come in a variety of designs ranging from the old-fashioned outhouse to the modern chambered versions where the composted residues are periodically removed and used as fertilizer. These modern systems usually include a port for adding kitchen scraps which are composted along with toilet wastes. Sawdust or other similar material is added after each use to control odors. (436) Some composting toilets work better than others. Check the following footnote reference for details. (437)

 

 

 

 

 

 
Water Recycling
 

 

 

 

 

 

 

 

Water recycling is another way to improve residential water use efficiency. Water recycling can occur on several levels. Home gray water systems (bath and sink water) may be as simple as draining bath and wash water into one's yard. Depending on the particular situation, more sophisticated systems may involve filtering, pumps, and disinfection. (438)

Graywater includes bath, sink, and water from washing clothing. It excludes toilet wastes. Food scraps and many soaps and shampoos present in graywater are not usually a problem since they can be broken down by soil organisms into nutrients that are used by plants.

In some states, home gray water recycling is illegal. [Check with local health officials] The reason for this prohibition is that graywater may be contaminated by harmful bacteria, viruses and parasites. Contamination can occur in a number of ways, such as washing diapers at temperatures too low to kill harmful organisms, or from the small amounts of fecal material that is washed off our bodies when we bathe. For this reason, gray water that has not been disinfected should not be used to directly water vegetable parts that are to be eaten or on lawn areas where direct human contact is likely. Although the use of graywater could be potentially harmful, "it's worth noting that health officials we consulted knew of no documented case of illness caused by gray-water use." (439)

Since there is a small possibility that diseases could be transmitted by graywater contact, graywater should be used carefully. (440) Graywater can be used safely to water fruit and other trees, or in landscaping. It can also be used for vegetables if it is applied sub-surface with a soaker hose or by some other sub-surface system. Sub-surface application is the most preferred way to use graywater because direct exposure to graywater is eliminated and soil organisms kill pathogens. (441)

Soaker hoses can also be used with relative safety on the surface in gardens since water applied by them does not splash onto the edible parts of plants. Although the uptake of pathogens by root crops does not take place, root crops watered with graywater should be carefully washed and/or well cooked before they are consumed.

To maximize safety, graywater can be disinfected before it is applied. Historically, water has been disinfected by adding chlorine. Chlorine does disinfect but its use can also result in the creation of compounds like chloramine. Chloramine, which is toxic to soil and aquatic organisms, results when chlorine reacts with the carbon in water borne organic materials. If the level of organic materials is low, the amount of chloramine created is small. But if the organic load is high, the amount of chloramine produced becomes a problem. Chlorine is also toxic to soil and aquatic organisms but it dissipates faster than chloramine.

If water is disinfected with ozone, this problem is avoided. Ozone, a form of oxygen that links three atoms of oxygen together, is even more effective at killing pathogens than chlorine and does not cause harmful side affects. It can also break down many organic pollutants and can be used to remove heavy metals through a process of precipitation. (442) Though the adoption of ozone water treatment systems in the U.S. has been slow, ozonization has replaced chlorine in 99% of the swimming pools in Western Europe. (443)

Soaps containing phosphates can also be used without negative consequences in most graywater recycling situations. Phosphate is a much maligned nutrient because it stimulates aquatic plant growth in lakes and waterways. These plant "blooms" can cause fish to die from suffocation. At night aquatic plants need oxygen which they extract from the water. If the number of aquatic plants in a volume of water is excessive, oxygen levels can drop below levels that can support fish. (444)

Excessive plant growth also threatens fish with suffocation when plants die in the autumn. With large quantities of dead plant material available, decay bacteria multiply rapidly. These bacteria require oxygen and can quickly reduce the oxygen content in a body of water to levels below which fish can survive. (445) In soil, however, phosphate is a nutrient readily useable by plants and need only be avoided if there is a possibility that the phosphate will enter a waterway instead of becoming part of a terrestrial plant.

Though they are usually thought of as waste elimination processes, septic tank leach field systems can be excellent water and nutrient recyclers. A leach field is made up of lines of perforated pipe buried 4 to 5 feet deep on level contours so that the wastewater is evenly distributed throughout the whole leach field. Additionally, leach pipes are surrounded by coarse sand and an 18" layer of one inch rocks to keep the perforated pipes from getting clogged by soil or plant roots. When wastewater leaves a house it passes through a septic tank where some of the solids are biologically broken down. From the tank the partially processed wastewater flows into the leach field where it seeps through the perforations in the pipe into the surrounding rock and then into the soil.

Once in the earth, soil organisms complete the process of killing pathogens and converting the wastewater borne nutrients into inorganic compounds which plants can use. The water that carries these waste materials provides irrigation. The recycling process is completed when plants watered and fertilized in this way lose their leaves, or die and decay to become part of the surface soil. These plant materials can also be recycled by collecting and composting them so the nutrients they extracted from the leach field can be used as fertilizer in other locations. Since leach fields pipes are typically laid at a depth of five feet it is essential that the plants grown in conjunction with them have roots that go deep enough (6 feet or deeper) to take advantage of the water and nutrients available. If leach field pipes are installed closer to the surface, plants with shallower root systems can also be used.

On whatever level it occurs, it is important to keep toxic and caustic materials, like some drain openers, out of recycling systems. These materials can damage or kill the various organisms that help in the recycling process. With the exception of lead from pipe solder or silver, which is a waste from photo processing, heavy metals and other industrial toxins are not usually found in graywater. But where industry is hooked into municipal treatment systems such materials are often present.

Heavy metals and other toxins can concentrate in the food chain when water or composted sludge contaminated with them is used to irrigate and fertilize plants. (446)

 

 

 

 

 

 
Community Scale Water Recycling
 

 

 

 

 

 

 

 

In dense urban areas, where many residences do not have yards, community sized wastewater recycling systems are a more practical choice for recycling wastewater. As with individual residence systems it is important to keep toxic and caustic materials out of all wastewater collection and recycling processes. If this is done there are a number of processes that can be used to clean up wastewater so it can be used for irrigation. In general such recycling systems use both biological and mechanical methods to clean wastewater.

Biological systems can be used exclusively where land availability is not an issue. In Arcata California a marsh system is used to treat the community's sewage. As the sewage flows through the marsh, aquatic organisms consume and convert the waste into nutrients that marsh plants then convert into plant growth. While the water in this system is not reclaimed for irrigation it does enhance the marsh's aquatic environment. (447)

Where land area is limited or expensive, the land area required for biological treatment can be reduced by additional human manipulation. The new Alchemist Institute under the direction of John Todd has developed a treatment process which uses greenhouses and translucent tanks to maximize decomposition and photosynthesis. As the wastewater flows through a series of semi-transparent tanks a complex community of aquatic plants and animals purify the water by consuming and converting the organic waste into animals and plants (biomass). At the end of the process, the clean water can be used for irrigation or it can be safely discharged into streams. In addition to water, the process also produces a crop of fish and other aquatic organisms and aquatic plants that can be composted and used as a soil amendment. (448)

A third approach has been developed in Tijuana, Mexico. The treatment plant in Tijuana is called Eco-Parque. The Mexican system combines biological and mechanical methods to process wastewater to minimize the amount of land needed for treatment. The treatment process involves mechanical screens, biological filters, clarification (slowing the flow of water so solids can settle out) and disinfection. The goal of this project is to recycle all the water and nutrients that pass through it. The recycled water is being used for irrigation and the nutrient rich solids are composted and used as soil amendments. (449)

 

 

 

 

 

 
Climate-Appropriate Landscaping
 

 

 

 

 

 

 

 

As in other areas, water use for landscaping and gardening can be significantly reduced. In low rainfall areas, the amount of water used for residential landscape irrigation can average 50 or more gallons per day per capita. (450) The use of water efficient irrigation equipment and selecting landscaping schemes and plants that are suitable for the climate where they are located can greatly reduce this requirement. Efficient water use in landscaping does not mean that landscaping themes have to be sparse. Even in arid areas there are numerous beautiful plants from which to select. (451) Nor does such a strategy preclude having a vegetable garden, fruit trees, or grass. Reducing water use in other parts of a landscape frees up water for these purposes.

If climate appropriate landscaping is combined with water efficient irrigation equipment, even more water can be saved. Water efficient irrigation equipment ranges from various drip irrigation systems and low flow drip emitters and sprinklers to sophisticated irrigation control tools called tensiometers. Tensiometers are electronic devices that are installed in the soil where they measure soil moisture content. They can be read and water applied accordingly or they can be used to activate automated irrigation systems when water is needed.

On the plant side, there are literally hundreds of attractive drought tolerant trees, shrubs, vines, and ground covers that can be included as part of a low water use landscape palette. (452) Additionally, there are numerous drought tolerant plants that produce food and other useful materials. These plants include the California Black Walnut tree, the fig family, the Oriental Persimmon, the Quince tree, members of the grape family, the Guava family, loquat trees, Aloe, Bamboo, and many more. (453)

Even modest efforts toward coupling water efficient irrigation systems with climate appropriate plants in landscaping could cut irrigation requirements in low rainfall areas in half. (454) If climate appropriate plants are used exclusively, irrigation requirements can be reduced to zero after plants become established. If graywater recycling systems are incorporated, even relatively water intensive landscapes can be successful without using potable water for irrigation.

 

 

 

 

 

 
Efficient Water Use In Industry
 

 

 

 

 

 

 

 

Just as in the residential sector, commercial and industrial users can cut water consumption through water recycling and use of water efficient fixtures and appliances. Changes in operational strategies and manufacturing processes can increase efficient water use even more. In 1978, U.S. manufacturing industries used each unit of water 3.4 times before it was discharged. By the year 2,000, experts predict that the water reuse rate for industry will have increased to over 17 times before discharge. (455)

Some innovative firms have already achieved or exceeded this level of efficiency. "Armco steel mill in Kansas City, Missouri, which manufactures steel bars from recycled ferrous scrap, (scrap iron and steel) draws into the mill only 9 cubic meters of water per ton of steel produced, compared with as much as 100-200 cubic meters per ton in many other steel mills -- the Armco plant uses each liter of water 16 times before releasing it after final treatment, to the river." (456) "One paper mill in Hadera, Israel, requires only 12 cubic meters of water per ton of paper (produced), whereas many of the world's paper mills use 7-10 times this amount." (457)

Pioneer Metal Finishing, a plating firm in New Jersey, has developed a water recycling process that totally eliminates sewer discharge. In the Pioneer process, all water is recycled and most of the chemicals and metals extracted from it are reused. Pioneer is now looking for a use for the small quantity of dry residue left over from their recycling operation. (458)

Water use in industry can also be cut by using non-chemical water treatment processes to prevent biological fouling and water scale buildup in boilers, water lines, and cooling systems. Non-chemical water treatment consists of exposing water to magnetic and electrostatic fields to prevent mineral scale from attaching itself to pipes and other metal surfaces and to remove such deposits where they already exist. Non-chemical treatment also creates an environment hostile to the growth of water borne bacteria, fungus, and algae.

The buildup of scale and bacterial slime reduces the efficiency of heating and cooling systems by restricting water flow rates and by insulating heat exchange elements. A 1/16 inch scale buildup requires 15% more fuel to achieve the same heating results. A 1/4 inch buildup increases fuel consumption by 39%. (459)

In the U.S., chemicals have been the predominant method used for treating such problems. But chemical treatments are relatively labor and material intensive because they need regular chemical mixture adjustments. Maintenance is also high because chemical treatments reduce the rate of scale build up but do not prevent it. This means that heating and cooling systems have to be drained and manually cleaned on a regular basis. Additionally, all the water in chemically treated systems must be periodically purged because evaporation losses increase the concentrations of chemicals and minerals beyond acceptable levels. This purging wastes water and releases treatment chemicals like algaecides, fungicides, bactericides, and phosphates into the environment. (460)

Non-chemical treatment minimizes or avoids most of these problems. Although they have been slow to catch on in the U.S., non-chemical treatment systems have been the preferred treatment choice in Europe and in the Russian Commonwealth for decades. But this is changing as is evidenced by the numerous high profile firms like Kodak, IBM, Hewlett Packard, Ford Motors, Holiday Inn, Pepsi Cola, Coca Cola, Marriott, and Bantam Books that have already switched to non-chemical treatment processes. (461)

 

 

 

 

 

 
Efficient Water Use: Other Benefits
 

 

 

 

 

 

 

 

In addition to saving water, using water more efficiently has other benefits. Efficient irrigation practices and growing water efficient crops help to avoid the build up of salt and other minerals in soils. As rainwater runoff travels over and through the ground, salt and other minerals are dissolved into it. When this mineral laden water is used for irrigation the salts and minerals it contains are left in the soil when the water evaporates or is transpired by plants.

If irrigation water is used efficiently there is less water to evaporate and thus less of a salt and mineral build up. A smaller mineral buildup makes it easier for rainfall or intentional periodic flooding to leach the accumulated minerals and salts out of the soil. Rainwater runoff from efficiently irrigated agricultural soils is also less salty than it would be with less efficient irrigation practices and is thus more useable for other purposes.

Efficient water use saves energy and minimizes energy related pollution by reducing the amount of energy required to pump water out of the ground and to deliver it from distant sources. It also means that fewer rivers will be dammed or otherwise modified, and that smaller less costly conveyance systems can be used to deliver water when local supplies are inadequate. More efficient water use also means that stored water will last longer during periods of drought.

Though the relationship is less direct, efficient water use also minimizes the environmental impact of building wastewater treatment facilities to treat urban sewage. With smaller quantities of water to treat, less energy, concrete, and other resources are needed to build and operate treatment centers. Reducing the amount of energy and materials needed to build and operate treatment systems also reduces the amount of watershed damage related to the procurement of such resources. By reducing pollution it also reduces the amount of pollution entering waterways and groundwater deposits.

 

 

 

 

 

 
Protecting Watershed Function
 

 

 

 

 

 

 

 

Another aspect of creating a more water secure future is the vital need to protect watersheds and the waterways and groundwater storage areas which they supply. A watershed is a drainage basin composed of a valley and the surrounding slopes which collect and direct the flow of rainfall and snow melt runoff.

Watersheds are also the home of complex interdependent plant and animal communities which are vital to watershed function and its health. Many watersheds are small. Usually smaller watersheds empty into larger ones. The great rivers of the world are all supplied by runoff from numerous smaller watersheds that result in one large watershed or drainage basin for each river. Actually all land areas above sea level are part of one watershed or another.

In a healthy watershed, rainwater runoff carries very little sediment and nutrients. Even when rainfall is heavy, streams and rivers run clean. This is because plant leaves and the ground carpet they form when they fall protect the soil from pounding rain. (462) Plant root systems, along with tunneling soil organisms, also help store water by making it easier for water to be absorbed into the soil. Rainwater and snow melt runoff are also slowed by this process.

By slowing runoff and storing water, watershed communities perform three important functions. First is the function of self preservation. By storing water and slowing runoff the watershed's plant and animal community perpetuates itself by insuring that it has an adequate water supply during dry periods. Second, the slow release of watershed stored water through springs evens out the flow of rivers and streams so they continue to flow long after the wet season has past. (463) Finally, this slowing and storage process helps to increase groundwater supplies by allowing more time for water to percolate down into groundwater aquifers for storage. In addition to providing the services just discussed, all the organic material in our planet's soils have been produced by the plant and animal communities that inhabit the world's watersheds.

In a healthy watershed, the processes described above happen naturally. But if we use watersheds inappropriately and extract resources from them incorrectly, the watershed community and the functions it performs will be crippled and can even collapse.

Watershed communities worldwide are under attack. If present practices persist, human activities will be driving "100 species (of plants and animals) to extinction every day," over the next three decades. (464) This "is at least 1,000 times the pace that has prevailed since prehistory." (465) At this rate, not only are we losing species, but whole ecosystems, the "nurseries of new life forms." (466) Harvard biologist E.O. Wilson describes this phenomenon as the "'death of birth.'" (467) "Wilson estimates that people have recently begun to extinguish lesser creatures at a pace 10,000 times the typical natural rate." (468) "British ecologist Norman Myers has called it the 'greatest single setback to life's abundance and diversity since the first flickerings of life almost 4 billion years ago.'" (469)

One might argue that the extinction of one or even thousands of species of life, in a world that is home to millions of species, is of little consequence. But the long-term effect of the loss of even a single species is not easily known. (470)

History has shown that eliminating certain organisms from an ecosystem can have unanticipated effects. Early in the 20th Century people in Kern County California waged a 20 year battle "against annoying predators: skunks, foxes, badgers, weasels, snakes, hawks, owls." (471) In 1924 the war against predators was escalated when Kern County sheep herders "hired a U.S. Biological Survey team to wipe out the coyotes." (472) By 1926 crop yields were the best ever, but by the following Spring the lack of predators resulted in Kern County being inundated by 100 million starving field mice which even killed and ate sheep in their hunger. (473)

Even when the target of animal control measures is the prey rather than the predator, problems can emerge. This was borne out in an experiment where rodents and rabbits were intensively poisoned and trapped in one area and then had their population levels compared with those of another area where such measures were not applied. The study found that the population levels of rabbits and rodents in the area where poisons and traps were used was soon larger than the comparison area where nature was not interfered with. The reason given for this phenomenon was that as poisoned animals died they were eaten by predators which died as well. With fewer predators available to eat them, the rodent/rabbit population quickly grew beyond previous natural levels. (474)

Even if poison is not used to kill prey animals, a substantial reduction in the prey animal population could cause a similar imbalance. If the population of prey animals is greatly reduced by any means, predator populations will fall as well as the result of starvation or through migration to where food is more plentiful. In the absence of predators, prey population will quickly grow beyond normal levels until the slower reproducing predator population can rebound.

 

 

 

 

 

 
Eco-nomic Watershed Use
 

 

 

 

 

 

 

 

We are still quite a ways from fully understanding all the intricacies of watershed mechanics. But in a general sense we know how present practices harm them and how watershed resources can be used in ways that minimize negative ecological impacts.

 

 

 

 

 

 
Agriculture
 

 

 

 

 

 

 

 

Agriculture, as it is commonly practiced, is not as effective at slowing runoff and storing water as the plant and animal communities it replaces. With conventional agriculture land is frequently unprotected by vegetation. Even when crops are grown the soil is often only partially protected compared with natural vegetation. When land previously farmed is converted to grassland or woodland "it will store roughly 16 more tons of carbon (embodied in plant material) than when it was cultivated." (475) Without protection, topsoil is easily eroded by pounding rain. Hard rainfall on bare soil often has the effect of sealing the soil surface so as to block water absorption. This speeds runoff and increases erosion down stream.

The use of chemical fertilizers in lieu of organic fertilizers can also increase soil erosion. Conventional agriculture often relies on chemical fertilizers to supply plant nutrients instead of using organic materials like manure and plant residues. A reduction in the amount of organic material in soils translates into less food for soil organisms. Fewer soil organisms means that there are fewer passageways in the soil through which water can be absorbed. Less absorption translates into more runoff which increases soil erosion. It also reduces the amount of water stored in the soil and as groundwater.

Once set in motion, the loss of fertile topsoil tends to perpetuate itself, making it harder for watershed communities to recover after they have been damaged. A weakened watershed function results in more erosion which further weakens the watershed community which causes more erosion and so forth. This is true whether agriculture is continued or if a natural watershed community tries to re-establish itself after agriculture has been discontinued.

 

 

 

 

 

 
Watershed Friendly Agricultural Practices
 

 

 

 

 

 

 

 

Even though many of today's agricultural practices are watershed damaging there are a wide variety of techniques that can be adopted to maximize the watershed function of agricultural systems.

One way to blunt the effects of pounding rain and runoff from rainfall and snow melt is to leave crop residues in the field. Plant residues can either be left standing or used on the soil surface as a mulch or in combination with mulch. Because its root systems are intact, standing vegetation can offer additional protection from water and wind erosion. Leaving plant residues in the field also helps watershed function by providing food for soil organisms. The tunnels they create in the pursuit of food make it easier for water to be absorbed by the soil.

There are a variety of tillage methods that can be used to prepare soils for planting that minimize the impact of agriculture on the watershed fabric. These include chisel plowing, strip tillage, ridge tillage, and no-tillage methods. Chisel plowing, a method of plowing that only opens a narrow furrow of soil, can reduce erosion losses by up to 50% over more commonly used cultivation practices. (476) "The use of no tillage, strip tillage, and ridge tillage ... can decrease erosion by 75% or more." (477)

Growing nitrogen fixing legumes along with crops and as rotation crops can also improve the watershed function of agricultural systems. These crops protect the soil from wind and water erosion and provide food for soil organisms which, in turn, make the soil more permeable by their tunneling activities. Adding organic materials to the soil, like manure, also improves watershed function. Manure-like materials absorb water like a sponge and provide food for tunneling soil organisms. "Increasing soil organic matter by applying livestock manure increased the water infiltration rate by more than 90% (Meek and Donovan, 1982; Sweeten and Mathers, 1985) mainly by decreasing the rate of water runoff (Mueller et al., 1984)." (478)

Planting trees and shrubs to form windbreaks is a good way to protect soils from the erosive effects of the wind. "Soil particles do not ordinarily blow away until wind velocity is about 13 miles per hour 1 foot above the ground." (479) A well established windbreak can provide full protection against wind blown soil losses "10 times the height of the trees measured in the direction the wind is blowing. And they give some protection as far out as 20 times the height of the trees." (480) Windbreaks also "make sprinkler irrigation more effective" by protecting "the spray against shifting winds." (481)

The use of windbreaks can also increase crop yields. "In a project aided by CARE in the Majjia Valley of Niger, for instance, trees planted to form windbreaks around cropland boosted grain yields more than 20 percent and also produced wood needed for fuel and timber." (482) Windbreaks also "increase both dew fall and the number of birds and small animals by providing cover, food, nesting sites, and storm protection. In summer, farmstead windbreaks raise humidity and produce an air conditioning effect. In winter, they decrease livestock deaths, heat, and feed needs." (483)

Though it is just one aspect of food production, the grazing of livestock on rangeland has a particularly negative effect on watershed function. Livestock grazing on range and forest lands decreases the water holding capacity of watersheds by removing soil protecting vegetation. (484) This translates into soil erosion which, in turn, results in less and weaker vegetation leading to further soil loss and eventually the formation of gullies. Topsoil loss in the U.S. is around 3.1 billion tons per year. (485) Around 85 percent of this loss can be attributed "to the feet of grazing livestock or to the production of livestock feed." (486)

As early as 1974 the Bureau of Land Reclamation reported "that less than one-fifth of the grazing lands in the United States were in "'good to excellent'" condition. (487) Even in forestlands, where one would expect that tree canopies would protect against erosion, livestock grazing has a negative impact. Soil erosion on grazed forestlands is "six times the rate experienced on non-grazed forestlands." (488) Grazing, especially grazing cattle, is particularly damaging to streams and stream related vegetation. Cattle cause damage because they break down stream banks and trample stream vegetation. "A 1990 EPA report stated that "'riparian areas through much of the West (in the late 1980s) were in the worst condition in history.'" (489) Livestock grazing has a similar effect on the rest of the planet. "Livestock grazing and livestock crop production cause accelerated soil loss over more of the globe than any other land use." Even if we do not count the land used to grow grain and other supplemental food for livestock, overgrazing livestock alone is the largest cause of soil degradation on our planet. (490)

If it is done carefully, domestic animals can be grazed on some range land areas without seriously compromising their watershed function. But to avoid serious damage, grazing and its timing need to be carefully regulated. Considering the damage that they cause to watersheds in general and to streams and ponds in particular, it may be advisable to prohibit livestock grazing, particularly cattle, which cause the most damage, in most range and forest land areas. The overall economic impact of such a policy in the U.S. would be relatively minor since only three percent of the beef grown nationally is rangeland fed. (491) It would be important however, to work with ranchers who earn their livings raising range fed cattle to mitigate any negative economic impacts that such a policy would create for them.

 

 

 

 

 

 
Watershed Function And Forestry
 

 

 

 

 

 

 

 

Timber harvesting is another way that human activity impacts watershed function. Clear cutting, the most prevalent method of timber harvesting, completely eliminates large stands of vegetation during the process of harvesting trees. This results in the almost total disruption of the plant and animal communities that are essential to the retention of forest soils, the water they store, and the water that percolates through them into groundwater storage basins. Though professional foresters do not agree completely as to the best strategy or strategies for both harvesting timber and protecting watershed communities, some general strategies are emerging.

If more than a few trees are harvested in one area they should be harvested in narrow bands along contours to minimize the problem of erosion. Harvesting vegetation counter to contours opens the soil up to the formation of erosion gullies. Trees close to waterways should only be harvested individually and if they can be harvested in a way that avoids waterway siltation. Stream siltation has been identified as a factor in the decline of salmon, and cut-throat-trout in the Pacific Northwest. (492)Forest floor debris or duff should be spread on soil areas disturbed by felling or from dragging trees or by logging equipment. This practice minimizes the effects of erosive rainfall.

Road building in forested areas should be limited. Often the grading of access roads can be just as destructive to watersheds as the harvesting itself. (493) In one study, a single road slide (caused by erosion) contributed to 40% of the sediment lost from the watershed area being examined during the study year. (494)

To avoid the need for roads, timber harvested in remote areas should be moved to transport centers by helicopters, horses, or balloons. Currently, around 8 percent of the logs harvested in the Pacific Northwest are moved to loading areas by one of these methods. (495) Only the tree boles, the main wood portion of a tree, should be removed from the forest. This portion of a tree is low in nutrients and its removal represents a relative minor nutrient loss to the forest ecology. Small branches and foliage, rich in nutrients, should be left in the forest. (496)

Some experts argue that forest ecosystem management practices should also permit some form of clearcutting as long as it mimics "nature and the effects of natural disturbances" like fire. (497) While this view certainly deserves study, it should be noted that logging in any form is not "natural" in that harvested trees and the micro-nutrients they embody are removed from the forest environment. Although there are parallels between clear-cutting and forest fires, we should be careful not to establish forestry policies based on such parallels until we are sure that such policies are truly sustainable. The negative impacts of clear cutting, like stream heating (See index for more details) and siltation and the accelerated loss of nutrients, certainly indicate the need for further study.

Under the general heading of "New Forestry" there are a number of experiments being conducted toward the development of sustainable forestry strategies. The U.S. Forest Service is currently experimenting with "the use of low-impact logging techniques to minimize the worst aspects of conventional forestry: soil erosion, habitat fragmentation, and homogenization of forests." (498) Forest homogenization refers to the condition caused when one species of same age trees are planted over a large area after it is clear-cut.

In an experiment in the Shasta Costa Valley in Southwestern Oregon, "foresters will carefully select the trees to be logged and those left behind as biological "legacies" that aid the recovery of the land. Mimicking the fires that occur on a 50-to-90 year cycle in the area, timber cutters will concentrate their work on the valley's dry ridges and avoid the sensitive stream side areas altogether. By concentrating timbering near existing roads on the valley's degraded edges and relying on helicopter logging for the rest, the project will minimize road building and the soil and habitat loss it causes." (499)

The University of Oregon is also getting into the sustainable forestry act. In one experiment "one-half acre patches of trees were harvested, creating a mosaic of small openings and wooded areas; researchers are studying whether young Douglas firs can grow in these filtered light patches." (500) Other researchers are creating intentional snags in larger clear cut areas. In these areas, the tops of remnant trees in larger clear cuts "were either cut off or blown off with explosives (they are trying to determine which approach A third experiment leaves a fairly large number of trees standing works better) to provide cavity-nesting trees for wildlife." (501) A third experiment leaves a fairly large number of trees standing after harvest. These "leave trees" are designed to create a mixed aged forest and a multi-level tree canopy. (502)

The goal of selective timber harvesting is to minimize the ecological trauma that results from clear-cutting. Indicative of this trauma is the change in stream temperatures after clear-cutting. In one study, stream temperatures went from a maximum of 57 degrees Fahrenheit to a maximum of 85 degrees after clear-cutting occurred. (503)

Soil erosion is another trauma caused by clear-cutting. This is particularly true where rainfall is heavy. "In the Amazon Forest, for example, a hectare (2 1/2 acres) of land may lose no more than 3 pounds of topsoil a year through erosion; when the land is stripped of its forest cover the erosion losses rise to 34 tons per hectare." (504)

A controlled deforestation experiment in the Hubbard Brook Experimental Forest revealed a number of other impacts. In this experiment "six contiguous watersheds, ranging in size from 12 hectors (30 acres) to 43 hectors" (106 acres) were studied as normally functioning forested areas. (505) During this period, forest inputs and outputs (nutrients, water, etc.) were measured to develop a baseline of information to compare with the second half of the experiment. This second phase consisted of completely leveling all the vegetation on one of the study watersheds with an area of 15.6 hectors (38.5 acres). After it was leveled, no material was removed "and great care was taken to prevent disturbances of the surface of the soil that might promote soil erosion." (506)

As the experiment continued, changes in the watershed were measured for several years and compared with the previous information. Even though the soil surface was not damaged and no vegetation was removed from where it was felled, the "deforestation had a pronounced effect on runoff." (507) In the first year after deforestation, runoff "exceeded the expected amount by 40 percent." (508) Runoff rates during one four-month period were over 4 times what would be normally expected. (509) Additionally, loss of key nutrients like potassium, calcium, and nitrate dramatically increased along with the organic soil base. (510) In short, the experiment illustrated how clear-cutting, even when vegetation is not removed, sets up a situation where rainwater runoff, soil erosion, and loss of key nutrients substantially increases. (511)

While clear-cutting dominates the forestry industry today, not all forests are harvested in this way. The 91,000 acre Collins Almanor Forestry operation in north eastern California is a case in point. Recently, the media has made much out of the apparent conflict between saving the forest from clear-cutting and preserving jobs for loggers. Meanwhile, the Collins Almanor foresters have been quietly harvesting timber sustainably and profitably for over 50 years. (512)

When they began harvesting the forest in 1941 it was estimated that it contained 1.5 billion board feet of lumber. A board foot of lumber is 12 inches by 12 inches by one inch thick. Since 1941, 1.7 billion board feet of lumber have been harvested from the forest--more lumber than the forest contained when harvesting first began. Yet, after over 50 years of harvesting, 1.5 billion board feet of unharvested timber still remain in the forest. "Even after decades of cutting, most stands in the Collins Almanor Forest still contain some magnificent 200- and 300-year-old trees with diameters reaching five and six feet." (513)

Over the 51 year harvest period "only a few trees were snaked out of the woods at a time" matching the forest's natural rate of regeneration. (514) Wood debris (leaves, needles, branches, etc.) is "left on the forest floor after logging, so more nutrients return to the soil." (515) Through this method, the forest has been profitably harvested while "wildlife, clear water, and recreational possibilities abound, even on land that has just been cut." (516)

To increase the forest's value as a wildlife habitat, some potentially harvestable trees are left in the forest to die. When the crowns of these trees break off they become snags which provide nesting habitats for "woodpeckers and other animals that require dead or dying trees." (517)

Further, the Collins Almanor forest does not contain tree stands of "even-age, single species management stands that clearcut logging produces; instead the stands have a variety of species and ages, the kind of mix that comes from letting the forest reproduce itself without artificial planting." (518) To protect streams from siltation, "logging roads are set well back from streams. The forest, in short looks and feels like a forest rather than a tree farm that is periodically mowed down and replanted." (519) Greg Apiet, a specialist in forest health for the Wilderness Society, has described the Collins Almanor forestry system as "impeccable." The management direction of the Collins Almanor forestry operation is not accidental. It was the vision of Trueman W. Collins who "envisioned a new kind of forestry operation that would yield a perpetual supply of timber for a mill that would never close". (520) In addition to receiving praise from the environmental community, the Collins Almanor Forestry Operation had been certified as sustainable by Scientific Certification Systems, a national independent environmental certification organization.

Scientific Certification Systems has also certified two other forestry operations as sustainable. The Menominee Tribal Enterprise forestry operation has been harvesting forestry products sustainably since 1854 in Wisconsin. Outside the U.S. the Noh-Bec and the Tres Garantias forest operations, which provide support for the community of Quintana Roo, Mexico, have also been certified as sustainable. (521)

In addition to timber, there are a number of other products that can be harvested sustainably from forests. A study conducted by botanists Robert Mendelsohn of Yale University and Michael Baick of the New York Botanical Gardens concluded more income could be generated in tropical forests by harvesting native medicinal plants instead of logging or using the land for agriculture. (522)

Another study in Peru demonstrated that "your average savvy forest dweller" could make almost $700 per year "by harvesting nine varieties of fruit, wild chocolate, rubber, and an occasional tree" from a plot of land "about the size of a suburban lot." (523) By comparison, if the lot were clear-cut it might gross $1,000, but of course a considerable time would have to pass before the plot could be harvested again if at all. (524) Studies of deforestation data "shows as much as 55 percent of the forest that is logged over eventually becomes deforested." (525) Globally, the rate of tropical deforestation has increased by 50 percent since the early 1980s. (526)

On another front related to using forests sustainably, "the pharmaceutical firm Merck and Company has signed a precedent setting agreement with Costa Rica's National Biodiversity Institute." (527) As part of the agreement Merck will "train Costa Rican biologist how to test specimens for medical properties" and provide them with the necessary equipment to do the job. (528) Merck will also pay a million dollars for the right to screen any promising plant or animal for pharmaceutical properties. (529)

The abundance of life forms in tropical forests makes them especially fertile ground for the discovery of pharmaceuticals. "Tropical forests cover only 7% of the earth's surface, but house 50% to 80% of the planet's species." (530) To date, "some 25% of the pharmaceuticals in use in the U.S. today contain ingredients originally derived from wild plants." (531)

 

 

 

 

 

 
Forestry And True-Cost-Pricing
 

 

 

 

 

 

 

 

As in other economic sectors, forestry practices are affected by economic conditions, not all of which are market driven. For example, U.S. "taxpayers lost $50 million in below-cost timber sales on Montana public lands alone" in 1991. (532) "Nationally, the Forest Service timber program lost more than $5.6 billion in the last decade." (533) Such subsidies undoubtedly have an impact on the economic choices the forestry industry makes. With true-cost-pricing such subsidies would be eliminated along with unsustainable forestry practices.

 

 

 

 

 

 
Land Development And Watershed Function
 

 

 

 

 

 

 

 

Land development is another way that watershed function is compromised. Current development practices often involve grading and rearranging the topography of large tracts of land. This process totally destroys watershed function.

A better approach is to minimize grading and topographical changes and protect native plant and animal habitats as much as is possible. Where grading and land movement are unavoidable, the area should be re-vegetated as soon as possible, after it has been disturbed. These practices will minimize the negative impact that development has on watersheds and will result in community and neighborhood designs that avoid the topographic monotony that characterizes most contemporary urban layouts.

 

 

 

 

 

 
Protecting Watersheds from Pollution
 

 

 

 

 

 

 

 

Watershed pollution is another threat to water security. Whether it comes from industrial or urban activities or from forestry and agricultural practices, once released, pollution is fated to be spread by the forces of wind and water throughout the whole watershed where it occurs and beyond.

Ultimately, the only way to control watershed pollution is to control it at its source. Admittedly, this is a very large task since it involves using new methods for doing almost everything we now do. Fortunately, many of the these methods have already been developed and are being put to use, though not even close to the scale that is needed.

 

 

 

 

 

 
Avoiding Pollution In And Around Our Homes
 

 

 

 

 

 

 

 

One way to reduce watershed pollution is to use more ecologically benign products and practices around our homes. Many of the products we use in and around our homes contribute to watershed pollution. These products include pesticides, paints, cleaners, and auto maintenance products. Less common pollutants include silver and other chemicals related to home film processing and residues from other home business and hobby activities. Until major changes are made in how some of the products we use are formulated, some watershed pollution is inevitable, but 90% or more of it can be avoided right now if consumers are selective when they purchase products and use them carefully. (534)

Purchasing products that are ecologically benign also sends a powerful message to manufacturers. It is the most direct way to let them know what we expect from the products we buy. How we spend our money in the present has a great deal to do with the kind of world we will have in the future.

For watershed friendly cleaning, look for biodegradable soaps and detergents. Avoid cleaners with chlorine based bleach in favor of those using oxygen bleach. Phosphorous-free soaps and detergents should be used in areas where wastewater may be discharged into aquatic environments. In aquatic environments phosphorous, a nutrient, causes excessive plant growth. Plants produce oxygen during the day but use it up at night. If too numerous, plants can deplete the dissolved oxygen in water during the night to levels so low that fish suffocate. (535) Excessive plant growth can also cause oxygen depletion in the autumn when aquatic plants die. When aquatic plants die, decay bacteria multiply. With an abundance of dead plant material, these bacteria, which require oxygen, can become so numerous that oxygen levels drop below what is needed to support fish. (536) These two phenomena, which are forms of eutrophication, can be avoided by keeping excessive nutrients out of aquatic environments.

Auto maintenance is another aspect of protecting watersheds from pollution. "According to the EPA, 91 percent of home oil-changers dispose of their used oil improperly, releasing 193 million gallons into the world at large each year." (537) Similarly, antifreeze and to a lesser extent brake, power steering, and transmission fluid frequently become watershed pollutants via the home mechanic route. Plus, used tires, batteries, oil filters, and other auto parts are often discarded improperly.

Because of the nature of the fluids and parts involved, a completely ecologically benign way to deal with them does not exist in most instances. But with proper handling their ecological impacts can be reduced as follows:

  1. Oil and antifreeze can be recycled. A new antifreeze called Sierra is being advertised as biodegradable. Call your County Waste Management or recycling agency to find out where oil and antifreeze can be recycled. Oil can be recycled and reused but it is often mixed with fuel oils and used as heating oil.
  2. Brake, power steering, and transmission fluid can be recycled in some areas. Call your County Health Department for information on where these fluids can be recycled.
  3. Tires that are not too worn can be retreaded and reused. Used tires have also been shredded and used in roofing tiles and rubber mats and added to asphalt and used as a paving material. (538) Ultimately, tires should be designed to be easily recycled and biodegradable so that the materials that wear off them will break down in nature.
  4. Watershed pollution can also be reduced if we use fewer paper products. Most paper products are bleached with chlorine or chlorine derivatives. A by-product of using chlorine in the papermaking industry is dioxin, a family of highly toxic compounds which includes Agent Orange, the notorious defoliant used during the Vietnam War. (539) Dioxin and other pollutants enter watersheds when paper mills discharge their wastewater.

In addition to the fear of general dioxin contamination, concerns have "been raised about direct exposure to humans, not only at bleaching plants but in dioxins leaching out of bleached paper products such as milk cartons and tissues. In Sweden, the use of chlorine in the bleaching of such products is now banned." (540) Actually, dioxin "is only the most notorious and highly publicized of about 1,000 chemicals emitted by pulp mills. Many are carcinogenic, and the effects of others are only now being discovered." (541)

The consumption of paper products can be reduced by using washable dinner napkins and kitchen towels instead of paper napkins or towels. Use the backs of paper printed on one side for notes and memos. Where the use of paper products is necessary, look for paper products that are not bleached or that are processed with oxygen prior to bleaching. Oxygen processing does not eliminate the use of chlorine but it does reduce the amount used. (542)

Use paper products made from post-consumer recycled paper. Post consumer paper is made with paper that someone has already used as opposed to many recycled paper products that are made from factory trimmings. A high percentage of post consumer paper in a product translates into fewer natural forest trees being cut to produce it and less natural habitat disruptions caused by plantation style pulp farms. Where the use of paper is unavoidable, choose unbleached paper products made from post consumer recycled paper. This is the best way to avoid paper related watershed pollution.

Using watershed-safe pest control products in our homes and yards is another way to protect watersheds from pollution. Many watershed-safe pest control products are already commercially available and the number of these products on the market is growing. But before buying pest control products, attention to house and garden keeping details, as the first line of defense against pests, should be explored. To control household pests, caulk cracks around baseboards and plug up holes around plumbing and heating ducts and electrical wiring. Make sure eave and basement vents are covered with screen mesh.

The primary pest control strategy in gardens is to maintain healthy plants. Healthy plants, like healthy people, naturally resist the attacks of pests and diseases. The key to maintaining healthy plants is to insure that they get the balance of nutrients they need from a healthy soil. Though nutrients in the form of chemical fertilizers can be added to the soil to make up for deficiencies it is better for soil health if organic materials like composted manures and plant residues, are used instead. As soil organisms consume these materials, nutrients are released at rates more closely matched to plant needs. The tunneling action of soil organisms also makes it easier for water and air, both essential for healthy plants, to enter the soil.

The slow release of nutrients by soil organisms also avoids the problem of nutrients getting into waterways and groundwater aquifers. With chemical fertilizers nutrients are often released faster than plants can use them. Thus water soluble nutrients are carried by runoff into waterways or leached into groundwater supplies. The findings of a national five-year Environmental Protection Agency study show this to be an increasing concern. Based on samplings taken from over 1,300 community water systems and rural wells, "the agency estimated that 57% of rural domestic wells contain nitrate, while 4.2% contain one or more pesticide and 3.2% contain both nitrates and pesticides." (543) This same EPA study showed that, "52% of community water systems contain nitrates, with 10% showing one or more pesticides and 7% containing both nitrates and pesticides." (544)

Beyond house and garden keeping details, the next level of pest control is the use of non-toxic mechanical measures. These include adhesives like flypaper, glue type mouse and roach controls, and sticky ant barriers like Tanglefoot. Flea combs and frequent vacuuming are effective flea control measures. Alternative pest control products are increasingly available in retail outlets that had previously carried mostly toxic pest control products. (545)

Using insects and other animals to control pests is another non-toxic strategy. Ladybugs, lacewings, and praying mantises are just a few examples of insects that eat other insects. Providing nesting boxes for insect-eating birds can also be an effective control strategy. Bats are valuable allies in the control of flying nocturnal insects like mosquitos which carry malaria and other diseases and moths whose larvae attack garden plants. Bat boxes, designed to accommodate sleeping bats, are useful tools in keeping bats around. Lizards, frogs, and toads are valuable insect consumers. Some lizards have been used effectively inside buildings to control roaches, flies, and other household insects.

On the microscopic end of the control spectrum are biocides or pest pathogens like BT (Bacillus Thuringiensis). BT is composed of the spores of a bacterium that are fatal to the larvae or worm stage of insects in the butterfly family. Included in this family are cabbage worms, tomato hornworms, and other leaf-eating insect larvae. Still in the research stage is the celery looper virus. This virus, which is effective at controlling a wide spectrum of pests is naturally occurring and could be commercially available in the next five years. (546)

Using homemade and commercial insecticidal soaps is another non-toxic way to control house and garden pests. Depending on the materials included in the mix, such concoctions can be totally benign or mildly irritating. Commercial products often contain alcohol as an emulsifier. Insecticidal soap sprays are effective against house pests like fleas and garden pests like aphids. Herbs can also be used for pest control. Some herbs, though not fatal to fleas, are useful in repelling them. (547)

Diatomaceous earth is another useful insect control material. Diatoms are the skeletons of tiny sea organisms. Diatomaceous earth kills insects by dehydrating or desiccating them when it comes in contact with their bodies. Though it is not toxic, it can be irritating to mucus membranes and lungs. Care should be taken to avoid breathing diatomaceous dust during its application. For indoor use diatomaceous earth can be applied directly to rugs to kill fleas and the excess can be vacuumed up after a few hours. In gardens it can be applied like any other pest control products on or around plants. (548)

Boric acid, only moderately toxic to mammals, marks the next level of the pest control regimen. Boric acid is the active ingredient in many commercial roach killers. It comes in both tablet and powder form. In tablet form it is mixed with a bait which is eaten by roaches along with the boric acid. In powdered form, insects walk through it and ingest the boric acid when they lick the dust off their legs. Since boron is toxic to plants in more than trace amounts, care should be taken when using boric acid around plants. If roaches are a problem around plants, boric acid tablets can be placed around them in upturned jar lids. This gives roaches access to the tablets and keeps the tablets out of direct contact with the soil. Where sprinklers or rainfall are an issue the tablet containers will need rain caps to keep them dry. Since boric acid is harmful to mammals if eaten, it should not be applied where children or pets can get to it. (549)

Pyrethrin, an insecticide originally derived from the chrysanthemum flower and now produced synthetically, is another relatively safe control measure. While quite toxic to insects, pyrethrin degrades rapidly into harmless byproducts and it is relatively non-toxic to animals and people. Nevertheless, pyrethrin should be used carefully since it is known to provoke asthma and allergy attacks in children and people with respiratory problems. (550) Pyrethrin is also toxic to fish and should not be used where ponds and streams would be directly affected.

 

 

 

 

 

 
Weed Control
 

 

 

 

 

 

 

 

For the urban gardener, pulling and/or hoeing weeds, in combination with mulching is one of the best and least labor intensive non-toxic weed controlling strategies. Where plants are already established, pull weeds or cut them down and cover with a four to six inch layer of leaves, grass clippings, straw, or sawdust. Do not use sawdust that has paint in it unless the paint is non-toxic and biodegradable. If properly covered by mulch, very few weeds will survive and the few that do manage to break through the mulch are easily pulled. Periodically more mulch will have to be added to keep weeds at bay. This is because soil organisms will be constantly turning the mulch into beneficial soil amendments from the bottom up. (551)

 

 

 

 

 

 
Watershed Pollution And Agriculture
 

 

 

 

 

 

 

 

Adopting non-polluting agricultural methods is another way to protect watersheds from contamination. The EPA has identified agriculture as the largest non-point source of surface water pollution. (552) Compared with the 9 percent of stream pollution that comes from industry, non-point pollution from agriculture approaches 65 percent. (553) "Pesticides and nitrate from fertilizers are detected in the groundwater in many agricultural regions." (554)

In the United States, groundwater supplies 95 percent of the drinking water in rural areas and 50 percent of the drinking water for all residents. (555) "Yet, according to a 1987 EPA report, at least twenty pesticides, some of which cause cancer and other harmful effects, have been found in groundwater in at least twenty-four states. In California alone, fifty-seven different pesticides were detected in groundwater." (556) Though this problem will be with us for some time, the rapidly expanding use of organic and other alternative farming methods, less dependent on petrochemicals, promises to reduce this kind of watershed pollution.

 

 

 

 

 

 
Using Organic Agriculture To Avoid Watershed Pollution
 

 

 

 

 

 

 

 

Organic farming is an alternative farming method that totally excludes the use of pesticides, chemically derived fertilizers, and other non-natural inputs. In organic farming nutrients are supplied by adding manures to the soil and by growing crops that convert atmospheric nitrogen into nitrogen compounds beneficial to plants. (557) Healthy soil makes for healthy plants which are naturally resistant to pests and disease. This is borne out by the fact that modern commercial organic agriculture is proving to be just as productive as is its petrochemical counterpart and less costly to practice even without including its true-cost advantages. (See chapter X for details.)

 

 

 

 

 

 
Watershed Pollution From Business And Industry
 

 

 

 

 

 

 

 

Watershed pollution from industrial and commercial operations can also be eliminated or reduced. Prior to World War II, U.S. "factories produced very few toxic by-products." (558) By 1985, the United States had "an estimated 50,000 toxic dumps as well as 180,000 toxic pits, ponds, and lagoons." (559) According to the EPA at least 14,000 of these sites are potentially dangerous. (560)

In 1985, 60 to 70 thousand chemicals were produced by the U.S. chemical industry and "approximately 1,200 new organic chemical products, with potential commercial value, are created in laboratories each year." (561) Of these new chemical compounds commercially produced each year, the EPA lists less than 50 thousand. Of those listed, "next to nothing is currently known about the toxic effects of almost 38,000 of them. Fewer than 1,000 have been tested for acute effects and only about 500 for their cancer-causing, reproductive, or mutagenic (gene mutating) effects." (562)

Three of the most common toxic contaminants of groundwater, chloroform, trichloroethylene, and trichloroethane, are produced by the organic chemical industry. (563) In all, "the U.S. Environmental Protection Agency has found that man-made chemicals have contaminated roughly 20 percent of the country's drinking water aquifers." (564)

While they are not the only generators, "a 1984 Environmental Protection Agency report found that organic chemical plants emitted almost 40 percent of air emissions of selected chemicals from industrial sources." (565) The organic chemical industry also "accounts for 83 percent of industrial discharges of hazardous organic chemicals to rivers." It also manufactures "over 5 billion pounds per year" of 14 organic chemicals, nine of which are hazardous. (566)

In practice, the volume of hazardous waste is much greater than the official numbers would indicate. This is because hazardous materials contaminate other materials like water which then become hazardous as well. In 1988, "manufacturers generated more than 290 million tons of hazardous waste regulated under RCRA (Resource Conservation & Recovery Act). Less than 5% was solid waste, the rest was wastewater." (567)

Besides the chemicals themselves, their production and use creates even greater quantities of toxic waste. "Air emissions of potentially toxic organic chemicals exceed five billion pounds per year." (568) Responding to federal regulations requiring them to report releases of toxic air pollutants, industry reported the release of up to 2.7 billion pounds per year. (569) (The discrepancy between 5 billion and 2.7 billion pounds probably has more to do with reporting methods than any appreciable reduction of toxic air emissions between 1985 and 1989 when the articles citing these figures were released.)

Another 412 million pounds of toxic waste are dumped into sewage treatment plants and rivers. (570) The "federal EPA estimated that more than 580 billion pounds of hazardous solid wastes are generated annually -- more than one ton for every person in the U.S." (571)

As large as the numbers just cited are, they do not tell the whole story. Specifically exempted from RCRA regulations are a host of other "high volume, low hazard" wastes. These include "cement kiln dust, utility company ash and sludge, phosphate mining wastes, uranium and other mining wastes, and gas and oil drilling muds and oil production brines, and some chemical process wastes." (572)

Of these exempted wastes, the mining industry is the largest contributor. According to former Secretary of the Interior Stewart Udall, "mining generates twice as much hazardous waste each year as all other industries and municipal landfills in the United States combined". (573)

The total "amount of unregulated waste is not known, but it is believed to be a much larger volume than regulated waste. In fact, various estimates inside and outside government put the amount of RCRA-regulated hazardous waste at just 10 to 50% of the total waste volume." (574)

 

 

 

 

 

 
Public Health And Toxic Waste
 

 

 

 

 

 

 

 

Obviously, coming into direct contact with toxic materials can be dangerous but direct contact is only part of the problem that toxic waste presents. Through a process called biological magnification some toxic materials can affect us by becoming increasingly concentrated as they move to higher levels of the food chain. Many of the chemicals we introduce into the environment are carried by rainwater runoff into streams, lakes, and estuaries. Once there, they are ingested by simple marine organisms which are eaten by small fish, which are eaten by bigger fish and so on. According to Larry Skinner, the principal fish-and-wildlife ecologist with the New York Department of Environmental Conservation, "Your chance of getting cancer from eating a weekly eight-ounce meal of trout caught in Lake Ontario is about the same as your risk of being murdered in the United States today -- about one in two hundred." (575)

Although numerous toxic materials can concentrate in food chains, some chemicals appear to be more pervasive. Polychlorinated biphenyls (PCB) still can be found in high concentrations in fish and wildlife even though it was banned in the U.S. in 1979. (576)

The use of DDT was banned in 1972 but it was still found in 334 of the 386 samples of domestic fish tested by the Food and Drug Administration in 1983. (577) Another contaminant frequently found in fish is chlordane, used to control termites and an EPA designated "probable" cause of cancer in humans. (578) Chlordane also persists where it is applied. Data submitted to the EPA by Velsicol Chemical Corporation of Rosemont, Illinois, the sole manufacturer of chlordane and heptachlor (also used to control termites), indicated detectable levels of these pesticides were found in the air of homes one year after they were treated. After reviewing the Velsicol data, the EPA estimated these levels of contamination "pose a lifetime cancer risk as high as 3.3 extra cases per one thousand adults exposed." (579)

Dioxins, associated with the production of paper, have also been found in fish. In September of 1990 the EPA "urged consumers . . . to avoid eating fish caught near 20 paper mills, including two in California, because of the cancer risk resulting from high levels of dioxin in the water." (580) According to the EPA, eating a regular diet of fish caught near the worst plant in Georgetown South Carolina, "would give a person a 1 in 50 chance of getting cancer". (581)

In some aquatic environments, toxic chemicals are so concentrated that even the fish that live there are getting cancer. In an article published in Forbes magazine in 1986 it was reported that "Up to a quarter of the English sole in 20 areas in Puget Sound are diseased." (582) Almost all the sauger perch taken from Michigan's Torch Lake are diseased. "Tumor-laden catfish" are also common in Ohio's Black River. (583) In all, "cancerous fish have surfaced in epidemic proportions in at least ten fresh and saltwater shorefronts and estuaries around the country." (584)

Since humans are at the high end of the food chain, pollutants can reach high concentrations in people who eat contaminated animal products. "Mother's milk in several east-coast states tests so high in PCB contamination that, if it were cow's milk, it could not be sold for human consumption." (585) This is certainly cause for concern. Infants are one step higher on the food chain than their mothers and are even more affected by pollutants during the first few years of their development than when they are older.

The bioaccumulation of toxins like the pesticides DDT and DDE and a class of industrial chemicals called PCBs has also been linked to breast cancer. One "study by Frank Falck, Jr., and colleagues in New York and Connecticut involved 40 Caucasian women who had breast lumps removed at Connecticut's Hartford Hospital from May through September 1987. Falck's group analyzed fatty tissue from the breasts of 20 women with cancerous lumps and 20 whose lumps were benign. In the breast-fat tissue of the women with cancer, Falck found significantly higher levels of DDT, DDE, and PCBs." (586)

Because of the small sampling, critics have suggested caution in drawing hard and fast conclusions from Falck's research. Falck counters that view by pointing out that the levels of chemicals found in the cancerous lumps were very high -- so high in fact that even if the researchers had "found considerably lower levels," they would have been "statistically significant" using standard statistical testing. (587)

"The National Cancer Institute agrees that Falck's data warrants concern, and is planning to begin an international investigation of toxic chemicals in breast fat and their relation to breast-cancer". (588)

Heavy metals, which come from a number of industrial sources, are another health problem concern. "Excessive exposure to toxic metals can cause health problems including kidney damage (chromium), impaired mental development (lead), and cancer (arsenic). (589) Methyl mercury attacks human nerve cells and causes numbness and loss of coordination, as well as hearing and visual problems. (590)

"Three-quarters of the 930 tons of mercury drifting in the atmosphere at any given moment is '"anthropogenic,"' or human-caused, most of it coming from the combustion of coal and trash." (591) Other sources include batteries and latex paint, which contained mercury until 1991. "Even Crematoria contribute their share, volatilizing the mercury in tooth fillings." (592)

 

 

 

 

 

 
Some Good Efforts To Reduce the Production And Use Of Toxic Materials
 

 

 

 

 

 

 

 

Although they are still more the exception than the rule, business and industry across the board are adopting more eco-nomically sound methods of production and operation. An important result of such efforts is eliminating or minimizing the use and creation of toxic or otherwise ecologically harmful materials that could pollute the watersheds on our planet.

Is it possible to eliminate all toxic emissions from industry? Monsanto, a large chemical company, must believe that it is. Monsanto "has already committed itself to zero" emissions. (593) In 1991 Monsanto's CEO "Richard Mahoney committed about $100 million to reducing air pollution an average of 90% at Monsanto's plants around the world by the end of 1992." (594) A press release by Monsanto on July 19, 1993 announced that Monsanto had reached this goal by changes in company operations on many levels. Monsanto reported that these changes "will eliminate 56 million pounds per year of toxic air emissions worldwide, including 16 million pounds per year in the United States, compared with those reported by the company in 1987." (595) Du Pont has also "endorsed the concept" of zero emissions. (596)

Another example of progress in reducing the production and use of toxics in industry is 3M Company. Through its "Pollution Prevention Pays" program, 3M has been able to reduce its use and creation of toxic chemicals and increase profitability at the same time. To avoid the use and production of toxic materials, 3M Company has changed production processes and product designs. Profitability has resulted primarily from using resources more efficiently and avoiding the cost of having to manage toxic materials. As reported in 1987, "3M, which started its own Pollution Prevention Pays program in 1975, claims a 50 percent reduction in all wastes over ten years for a savings of $300 million and is still working hard at it." (597)

Since 1987 3M's Pollution Prevention Pays program continues to chalk up savings. To date, 3M's efforts have "eliminated more than 500,000 tons of waste and pollutants" for a total savings of $482 million. 3M has saved another $650 million through more efficient energy use. (598)

Like Monsanto and 3M, Cleo Wrap, the world leader in the production of gift wrapping paper, is making progress in eliminating toxic materials in its operations. Since it implemented its waste reduction program, Cleo Wrap has saved $35,000 a year in waste disposal costs. In the process the Memphis, Tennessee based firm has nearly eliminated its generation of hazardous wastes by switching from solvent-based to water-based inks in its printing process. Additionally, the company has reduced its fire insurance costs because it no longer stores combustible solvents. Cleo Wrap saved even more money by eliminating its underground solvent storage tanks, thus also avoiding the high costs of complying with new federal regulations governing such tanks. (599)

The Borden Chemical Company in Fremont, California is another example. Borden Chemical has reduced pollution by changing how it cleans its filters and tanks. Borden has also changed how urea and phenol resins are pumped from tanks and how materials are transferred from tank cars to storage tanks. With these improvements the company has been able to reduce the organics in its wastewater by 93% since 1981. These changes have also saved Borden the expense of maintaining an on-site wastewater treatment facility. (600)

Although it may not be true in every case, it appears that even without true-cost-pricing most firms benefit economically when they implement waste reduction programs. An EPA study found 93% of the companies that invested in waste reduction strategies had a payback on their investment of less than four years. For over half the firms the payback was less than one year. (601) These paybacks do not include the potential savings of pollution control for society. Just in the area of health, "one estimate puts medical bills avoided by pollution control at $40 billion per year." (602)

In spite of obvious advantages of toxic materials reduction, toxic waste management has attracted the lion's share of financial support from federal and state governments. Unlike reduction which eliminates hazardous wastes altogether, waste management only moves the problem around or causes new problems when toxic materials are incinerated. Nevertheless, "of the $16 billion spent each year by local, state, and federal governments, only $4 million was spent on waste reduction in 1986. Or as a report by the U.S. Office of Technology Assessment put it, pollution control measures "receive more than 4,000 times the amount of state and federal funding as do efforts directed at waste reduction." (603) The rest was allocated to programs designed to control and manage the waste once it was produced." (604)

In addition to implementing true-cost-pricing, reducing the use and creation of toxic materials at their source could be greatly accelerated if government policies were modified to encourage toxic waste reduction instead of just its management. (605)

 

 

 

 

 

 
The Economic Impact Of Environmental Protection
 

 

 

 

 

 

 

 

Some people have argued that environmental protection hurts the economy, even though the examples just cited contradict this notion. This is not to say that all environmental regulations make sense from the perspective of eco-nomic security. But even with less than perfect rules, environmental protection seems to make economic sense. "Indeed, some of the leaders in global economic competition, such as Japan and Germany, have some of the most restrictive environmental rules." (606)

In Germany, stricter environmental regulations have had the added bonus of catapulting Germany into the global lead in the patenting and exportation of air-pollution control equipment and other environmental technologies. "In contrast, about 70 percent of the air-pollution control equipment sold in the United States is produced by foreign companies." (607)

 

 

 

 

 

 
Efficiency and Renewable Energy:
Developing A Watershed Friendly Energy Plan

 

 

 

 

 

 

 

 

The pollution of watersheds can be greatly reduced by becoming more energy efficient and switching to renewable energy resources. The conventional energy sector of our economy (fossil fuels and nuclear power) is a substantial watershed polluter. Pollution from fossil fuels includes:

  1. Acid deposition, (ie. acid rain, fog, dew, snow, and dry deposition).
  2. Volatile hydrocarbons and ozone (ozone, though not a direct fossil fuel pollutant, results when the energy of sunlight causes an ozone producing reaction between gaseous hydrocarbons and atmospheric oxygen.) Low atmosphere ozone and acid deposition as separate agents and in combination, "are the main contributors to forest death along the East and West Coasts and to about $5 billion in crop losses in the Midwest". (608)
  3. Smokestack particulates (i.e., soot, ash, heavy metals, etc.), acids and heavy metals that leach from coal mines and coal mine tailings, and drilling mud and other residues associated with drilling for oil and natural gas and oil spills themselves.

The petroleum industry alone accounts for 3 percent of the hazardous solid wastes generated in the U.S. each year. (609)

Pollution related to the nuclear power industry includes wind and water borne radioactive residues that result from uranium mining, ore milling, and the improper handling of uranium mine tailings, the release of radioactive materials during fuel processing, and from power plant operation and waste storage. (610)

The most important aspect of a watershed friendly energy policy is efficient energy use. If energy is used efficiently, less energy related pollution is created. Using energy more efficiently does not mean having less energy services such as having a warm, well lighted home and working environment. It means providing these services in ways that use energy more intelligently. For example, a well insulated, weatherized home equipped with day-lighting features and state-of-the-art electric lighting can provide all the comforts we desire while using a fraction of the energy used by the typical energy wasteful house.

After energy efficiency, switching to more ecologically benign renewable energy resources is the next most important step we can take to protect watersheds from energy related pollution. Other than constructing and maintaining the equipment for capturing it, the use of solar energy does not cause pollution or waste products. If solar collectors are designed properly, even the impact of building and maintaining such equipment can be almost eliminated.

 

 

 

 

 

 
Watershed Restoration
 

 

 

 

 

 

 

 

The restoration of watersheds that have already been damaged is another important aspect of increasing water security. Watershed restoration is a relatively new science and much research in this area is still needed. Nevertheless, some success in re-establishing ecologically stable watershed systems has been achieved. (611)

Watersheds are made up of complex relationships between plants and animals and their restoration requires much more than just planting trees and ground covers. Restoration requires a deep understanding of how specific biological communities evolve and how different species of plants and animals colonize a particular environment.

For example, after a fire, seeds from pioneering plants are carried by wind, water and animals from locations not affected by the fire to the burnt-over area. The seeds of some plants, like the Jack Pine, actually depend on fires to complete their reproductive cycle. Their cones will not open to release their seeds unless they are heated by fire. (612) As these pioneering plants grow they provide shade which is conducive to the development of under-story plants as well as providing cover and habitat for forest animals.

As with nature, human assisted restoration requires strategies that recognize the complex relationships between plant and animal communities and the environment they inhabit. Such strategies largely consist of letting nature be the guide while looking for opportunities to enhance the natural processes involved.

One strategy that has been used successfully in the Feliz Creek area in Oregon has simply been to increase the survivability of seedlings that sprout naturally by installing curtain fencing around them to keep browsers like deer from destroying the young trees. (613) Once these trees are tall enough to escape damage, the curtain fencing is removed. This approach can be enhanced further by replacing soil nutrients lost to erosion and by planting pioneer community plants to aid the natural reseeding process.

Strategies to correct other types of watershed damage are also being developed. A firm in Montana has developed a vacuuming technique that sucks up the eroded material which covers the pebbled spawning beds that are essential for the reproduction of many species of fish. To complete the process the recovered silt and other debris must be returned to the newly forested areas where it originated. This vacuuming technique can also be used to remove toxic mining sediments from stream beds. Obviously, such contaminated materials should not be spread on the land. One possible solution would be to seal it up inside played-out mines.

 

 

 

 

 

 
Re-establishing The Beaver
 

 

 

 

 

 

 

 

Another watershed enhancement strategy is to reintroduce beaver into damaged forest areas where forests have not been clear-cut or as newly restored forests are maturing. Beaver dams prevent erosion by checking the flow of spring runoff. This checking process also aids groundwater recharge by allowing more time for water to be absorbed into aquifers.

Beaver ponds also form the foundation of a cyclical process that supports a rich variety of plant and animal communities. New beaver ponds provide homes for "otters, muskrat, mink, ducks, fish, turtles, frogs, wading birds -- and continue to do so for as long as it is surrounded by a substantial number of the beaver's preferred food trees. When these are used up, the (beaver) colony moves on, its forsaken dams break, and the pond drains." (614)

"The rich mucky bottoms of what once were beaver waterworks give rise to an entirely different type of vegetation. Meadow plants take root and grow and these support a new array of animals, deer and voles and rabbits, which in turn, become the food base for land predators, foxes, bobcats, coyotes, weasels, hawks." (615)

With the passage of time the meadow "is colonized by trees, the first to pioneer being willow, birch, and aspen -- species the beaver relish. As the forest matures, beavers once again return and turn the place into a pond. First they dam what water trickles through the wooded tract, thus drowning a certain number of trees." (616)

These trees, in turn, serve yet another succession of creatures. "Woodpeckers, owls, kingbirds, and flying squirrels find nesting sites in their decaying trunks. Nuthatches, chickadees, and brown creepers feed on the insect life that proliferates in the rotting wood. Great blue herons construct huge nests on the forked tops of these forest relics. The big gangling birds, whose eight-foot wingspans prohibit flight through dense canopies, now enjoy plenty of clearance to take off and land on the towering eries (nests) they construct. And at the base of these huge nests, crayfish and other aquatic creatures breed in the rising water, providing the herons plenty of food for their chicks." (617) Finally, "the drowned trees become so weakened by decay that they topple into the water," where continued decay releases nutrients that settle "on the pond bottom, enriching it for that future day when the site will once again explode with meadow plants." (618)

The complexity of watershed communities and the difficulties and costs involved in restoring them once they are damaged, underlines the importance of protecting existing watersheds from damage in the first place.

 

 

 

 

 

 
Groundwater Management
 

 

 

 

 

 

 

 

Groundwater is becoming an increasingly important aspect in maintaining and enhancing water security. The two principal considerations in groundwater management are to keep water extraction rates below the rate of natural recharge and to prohibit the release of toxic materials in watersheds. If toxic materials are released in a watershed they can easily percolate into groundwater deposits. In addition to not exceeding natural recharge rates, groundwater use rates should be reduced to less than 80% of the aquifer's natural recharge rate, where groundwater has been depleted, until historic groundwater levels have been restored. In some cases groundwater deposits can be overdrawn without causing problems like the collapse of water holding deposits or salt water intrusion but these are particular situations that should not be taken as a general rule. (619) The potential to artificially recharge groundwater storage basins with recycled sewage water is another option.

 

 

 

 

 

 
Protecting Groundwater From Pollution
 

 

 

 

 

 

 

 

One of the most important aspects of protecting groundwater from pollution is restricting the use of toxic chemicals in any area where their use could result in the contamination of groundwater supplies. Pollutants in groundwater disperse very slowly. The flow rates of aquifers may "vary from five feet per day in rainy areas to five feet per year in deserts." (620) Most aquifers do eventually empty into an ocean but this process can take from tens to thousands of years and ocean pollution is certainly not desirable. Land locked aquifers have no way to clean themselves if they are polluted.

Even more or less non-toxic materials can cause serious groundwater problems. Chemical fertilizers and organic pollutants like feed lot runoff are two examples. Chemical fertilizers are highly water soluble. They can easily become groundwater contaminants as the water they are dissolved in percolates into groundwater supplies. One effect of this kind of contamination is nitrite poisoning which occurs when infants drink "well water contaminated with the nitrate ion (NO3-) from artificial fertilizers." (621)

Adult digestive systems can metabolize NO3- safely, but "the digestive tracts of young children contain bacteria capable of converting NO3- to NO2". (622) When NO2 is absorbed into the blood it chemically binds up hemoglobin (red blood cells). With less hemoglobin available to absorb oxygen when red blood cells pass through their lungs, children become anemic. This affliction, which is called methemoglobinemia, or the blue baby syndrome, can reduce an infant's resistance to disease and cause retardation and death in extreme cases. (623) Studies have also "suggested that elevated nitrate concentrations in drinking water may be associated with other health problems ranging from hypertension in children to gastric cancer in adults and fetal malformations." (624)

Organic pollutants like the runoff from feed lots present a special problem in aquifers. Unlike surface waters, the absorption of oxygen by groundwater is at best minimal. Without oxygen to support the growth of decomposing bacteria it can take hundreds or even thousands of years for organic pollutants in groundwater to decompose.

Another important aspect of groundwater management is the protection of groundwater recharge areas. In general groundwater recharge takes place where surface materials are porous such as in river valleys. Sand and gravel, carved out by swift running tributaries, settle out when rivers slow down in flat valley areas. This settling out process forms alluvial deposits which absorb and store rainwater that would have otherwise drained into the oceans. The voids between the individual pieces of sand and gravel in an alluvial deposit provide both openings for absorbing water and space for storage.

To protect these deposits, activities that decrease groundwater recharge rates or ground water storage capacity should be carefully controlled. This would include restricting gravel and sand mining in ground water storage basins. Mining alluvial deposits reduces the storage capacity of ground water storage basins. Restrictions should also limit development on ground water recharge areas. Buildings and their associated parking lots and roads speed runoff and block water from being absorbed into groundwater systems. Agriculture on alluvial deposits should be designed to maximize watershed function. (See index for more entries.)

A third groundwater issue is keeping the groundwater use rate well within its recharge rate. If groundwater is extracted faster than it is naturally recharged, the void or drop in the fresh water table can cause salt water intrusion. Salt water intrusion general occurs near the ocean but groundwater can be contaminated by brackish prehistoric water if such waters underlie or lie close to the alluvial deposit from which water is being extracted. (625)

A related issue to groundwater depletion is land subsidence. In the San Joaquin Valley in California, the depletion of groundwater supplies has caused the ground to sink "nearly thirty feet in some places." (626) Land subsidence can be damaging to roads, irrigation canals, wells, buildings, etc. (627) Land subsidence can be particularly damaging to water treatment facilities which are particularly "sensitive to changes in elevation. (628)

 

 

 

 

 

 
Improving Water Infrastructure Security
 

 

 

 

 

 

 

 

Implementing more eco-nomically secure water collection, storage, and delivery infrastructures is another way to increase water security. Currently, most water infrastructures are very vulnerable. This vulnerability exists on two fronts: vulnerability to natural phenomenon like earthquakes and vulnerability to human threats like sabotage. This is particularly true of water infrastructures that are dependent on aqueduct systems that deliver water from distant sources. Though the weaknesses inherent in any specific water infrastructure may vary, they primarily fall into the following categories.

 

 

 

 

 

 
Dams
 

 

 

 

 

 

 

 

Dams, used to collect and store rainwater and snow melt runoff, are vulnerable to earthquakes and sabotage. A "study at the University of California at Los Angeles revealed that the failure of certain dams in the U.S. could cause tens of thousands of deaths and one of them could cause between 125,000 and 200,000 fatalities." (629)

Compounding this problem is the fact that large dams can cause earthquakes themselves. This is because the weight of the water they contain puts pressure on the geological formations which lie under the storage area.

Even if dams were failure-proof, their useful lives are limited because they eventually fill up with silt. Where the watershed that drains into a reservoir has been severely impacted by deforestation, animal grazing, and watershed damaging agricultural practices, this process can be very rapid.

"The Tehri Dam in India, the sixth-highest in the world, recently saw its projected useful life reduced from one hundred to thirty years due to horrific deforestation in the Himalaya foothills. In the Dominican Republic, the eighty-thousand-kilowatt Tavera Hydroelectric Project, the country's largest, was completed in 1973; by 1984, silt behind the dam had reached a depth of eighteen meters and storage capacity (of the dam) had been reduced by 40 percent." (630) A more extreme example is the Sanmexia Reservoir in China. Commissioned in 1960 the Sanmexia Reservoir was completely silted up by 1964. (631)

In the U.S., siltation, caused by ill-conceived forestry, grazing, agricultural, and development practices, is also a mounting problem. For example, "in thirty-five years, Lake Mead was filled with more acre-feet of silt than 98 percent of the reservoirs in the United States are filled with acre-feet of water." (632)

Since 1963 the rate of siltation in Lake Mead has decreased but the reduction of reservoir capacity on the Colorado River has if anything speeded up. The silt that was formerly filling up Lake Mead "is now building up behind the Flaming Gorge, Blue Mesa, and Glen Canyon dams," which are upstream of Lake Mead. (633)

Depending on watershed conditions and whether a dam is protected from silt by upstream reservoirs, the rate of siltation can vary widely. During the ten year period from 1963 to 1973 the Black Butte Receiver in California lost 8.2 percent of its capacity. (634) In a 28 year period the Alamagordo Reservoir, on the Pacos River, lost 30 percent of its capacity, over one percent of its capacity each year. (635) The loss of capacity in Lake Waco on the Brazos river in Texas over a thirty-four year period was 61 percent or almost 2 percent per year. (636)

 

 

 

 

 

 
Strategies For Reducing The Problem Of Siltation
 

 

 

 

 

 

 

 

The problem of siltation can be greatly reduced if watershed friendly methods of forestry, agriculture, and development replace their watershed damaging counterparts. It is much less expensive to protect a watershed's function in the first place and very expensive to repair it once damaged. A deforested watershed in Costa Rica "has greatly shortened the life of an expensive hydroelectric dam" and to save the capacity that is left the government is considering reforestation. (637) According to the Costa Rican Minister of Industry, Energy, and Mines, the watershed that serves the dam "might have been protected 20 years ago for a cost of $5 million. Now the government must reforest the watershed at ten times that price." (638)

Even under the best conditions dams will eventually silt up. (639) As Raphael Kazmann, one of the most respected hydrologists in the world, puts it, "dams are wasting assets. When they silt up, that's it." When asked about the possibility of removing silt from them, he replied, "Sure, but where are you going to put it? It will wash right back in unless you truck it out to sea. The cost of removing it is so prohibitive anyway that I can't imagine it being done. Do you understand how many coal trains it would take to haul away the Colorado River's annual production of silt? How would you get it out of the canyons? You can design dams to flush out the silts nearest to the dam, but all you get rid of is a narrow profile. You create a little short canyon in a vast plateau of mud. Most of the stuff stays no matter what you do." (640)

In a attempt to lengthen the useful life of some of its small retention reservoirs, Los Angeles California spent $29.1 million dollars to remove 23.7 million cubic yards of mud that had accumulated in them. At this rate of $1.23 per cubic yard, "it would cost more than a billion and a half dollars, in modern money, to remove the silt that has accumulated in Lake Mead, over thirty years -- if one could find a place to put it." (641)

 

 

 

 

 

 
The True-Cost Of Hydropower
 

 

 

 

 

 

 

 

Potential dam failure, siltation, flooding of agricultural soils and wildlife habitats, and the dislocation of people are just some of the costs that should be included in a true-cost-pricing analysis to determine whether a dam should be built or not.

This is the opinion of Bill Robertson, an engineer and a member of the Global Environment and Technology Foundation and the Army Corps. According to Robertson, "A dam may be built with a design life of 100 years," but its "life-cycle consequences could go on for 300 or 400 years. So in the process of thinking through whether we want a dam, there needs to be that kind of reflection on life-cycle consequences. And the bigger the project, the greater the consequences and the greater the thought." (642)

The Aswan High Dam in Egypt is a classic example of how the lack of attention to a broad lifecycle analysis can lead to costly problems. The Aswan High Dam was built to store water for irrigation, to control flooding, and to provide hydroelectric power. Although the project achieved these goals to some extent, its construction caused a myriad of other problems, which had all been predicted by an eminent Egyptian hydrologist prior to the dam's construction. (643)

As predicted, the dam failed to provide the quantity of irrigation water predicted. Some of the water was lost because of excessive seepage. More was lost because the large open water lake created by the dam facilitated wind flows that accelerate evaporation. (644)

Added to this, silt, which had historically been deposited in the lower Nile Valley during flooding, is now trapped behind the dam. Nile Valley farmers now have to buy expensive imported fertilizers which are inferior to the silt that has been cut off. (645)

Below the dam, the now silt-free river has proven to be more erosive than in the past and it is under cutting river banks, bridge abutments, and dikes more rapidly than before the dam was built. (646)

The dam is also keeping nutrient-rich silt laden water from flowing into the Eastern Mediterranean Sea. This has reduced the production of marine life. Since the dam was built the sardine catch "has dropped by 18,000 tons a year." (647)

The lack of spring floods has also led to a 20 percent increase in the parasitic disease bilharzia (schistosomiasis). One stage in the life cycle of the bilharzia parasite takes place in the body of an aquatic snail. Historically, spring floods washed a large number of these snails out to sea, interrupting the parasites life cycle and reducing the number of snail hosts. (648)

Even using the water impounded by the dam for irrigation has caused problems. When water from the dam's reservoir is used to irrigate hot arid land, it evaporates quickly. The minerals left behind cause soil salinity to increase rapidly. Drainage systems to control this problem can be installed but will ultimately cost as much as the original dam. (649)

Given that desilting is cost-prohibitive and that new dam sites are scarce, a more water efficient future is vital to our water security. Likewise, energy efficiency and a switch over to more permanent renewable energy resources is also in order. As silt builds up in our nation's and the world's reservoirs, their capacity to store water and produce hydro-electric power will also be reduced and eventually eliminated altogether.

 

 

 

 

 

 
Water Storage Problems
 

 

 

 

 

 

 

 

In addition to the problems previously discussed, water stored in open reservoirs is subject to evaporation. As much as 100 percent of the water stored in reservoirs less than 10 feet deep in arid areas can be lost to evaporation. (650) These evaporation losses also reduce the quality of the water that does not evaporate because the minerals left behind in storage become more concentrated.

Beyond natural phenomena like earthquakes, siltation, and evaporation, dams are vulnerable to sabotage. Water stored behind dams can be easily contaminated, either directly or by contaminating rivers or streams that feed into them. The recent accidental herbicide spill into the Sacramento River in California is tragic testimony to how easily such contaminations can take place. Characterized as a "Biological Hiroshima" (651), the spill contaminated 45 miles of the upper Sacramento River and the water stored behind the Shasta Dam. (652)

Dams are also vulnerable to sabotage with explosives. Using explosives to destroy dams is a relatively easy way to cause hardship to a society during periods of conflict. Not only does it eliminate a water supply, it is a weapon that destroys anything downstream of the rushing water that a failed dam releases. If the terrorists who exploded a bomb in the World Trade Center had used the bomb to destroy a major dam instead, one can only imagine the loss of life and property damage that would have occurred.

Aqueducts are even more vulnerable than dams to earthquakes and sabotage. Aqueduct delivery systems consist of open water channels, pipe lines, pumping stations, and in-transit reservoir storage. Aqueducts are especially vulnerable because they often cross or lie in close proximity to earthquake faults and other hazards. They can also be damaged by sabotage at almost any place along their route. Since many aqueduct systems require substantial amounts of electrical power to pump water over obstacles like mountain passes, water delivery can be interrupted by knocking out power plants or transmission lines that are distant from the pumping stations they supply. Even without dramatic events like earthquakes and sabotage, aqueduct systems can fail. Aqueduct failures have been caused by flash floods, rock slides, and pipe failures.

 

 

 

 

 

 
Improving The Eco-nomic Security Of Water Infrastructures
 

 

 

 

 

 

 

 

Improving the security of our water infrastructures needs to be addressed on two levels. First, water security can be improved by reducing the dependency of urban and agricultural areas on imported water. Second, make better use of local water resources. In both cases, this can be accomplished by using water more efficiently and through the protection and sustainable management of local watersheds and groundwater storage areas.

Using water efficiently helps reduce the need to import water by getting more work out of local water resources. Efficient water use helps to extend the life of local water supplies if imported water supplies are interrupted by infrastructural failures or during periods of drought.

Protecting watersheds and groundwater storage basins allows a region to make the most of any local precipitation by increasing the amount of water available for collection and storage. Even though watersheds and groundwater storage areas are not part of the human constructed infrastructure their protection and sustainable management is vital to minimizing an area's dependence on imported water. (See Section on Watershed Function.)

Sustainably managed watersheds and groundwater storage areas are also vital to the longevity and effectiveness of human created infrastructure which extracts water from them. A healthy watershed can greatly extend the useful life of reservoirs by reducing the rate of siltation.

On a second level, water security can be increased by reducing the vulnerability of water infrastructures to natural and human created hazards. High on this list is protecting watersheds from pollution. Though it cannot eliminate intentional contamination, protecting watersheds from agricultural and industrial pollution helps to keep the water collected from a watershed from being contaminated by pesticides, mine wastes, and other pollutants related to human activities. (See index - watershed pollution from Industry and Agriculture for Details.)

Another way to reduce water infrastructure vulnerability is to replace open reservoir storage with underground tanks. The technology for the construction of such tanks is already well established. Though such a tank system would be applicable for most water infrastructure storage requirements, it would be most relevant in urban settings. Since the typical urban environment is made up of numerous smaller community units one or more tanks would be located in each of these communities.

The number of tanks, their capacities, and their locations would depend on a community's geology, topography, population and population distribution. Since tank covers are supported structurally by columns, the areas over them can be used as parks for picnicking and for recreational activities like tennis, basketball, baseball, and soccer.

Covered underground tank storage has numerous advantages over open reservoir storage. Covered underground tanks are less vulnerable to earthquakes than are dams. Large impoundment dams are very tall, some over 300 feet, and must be able to totally support the water stored behind them. (653) Tank walls are shorter, usually less than 50 feet.

The cylindrical shape of tanks also makes them very strong. Additionally, the walls of underground tanks get extra support from the earth that is packed in around them after they are completed. Because they hold smaller quantities of water, storage tanks put less pressure on the geologic formations which underlie them than do large dams. Thus underground tanks are less likely to cause earthquakes than are large reservoirs.

A second consideration is the destruction that occurs if a dam fails. Unless a dam is remote, its failure usually results in a substantial loss of property and life, caused by the rapid release of a large quantity of water. (654) If an underground tank fails, the water in storage would be contained by the surrounding earth. At worst, the released water would slowly seep away. This would give plenty of time to pump the escaping water to another storage facility or to dissipate it safely.

Unlike dams which must be built in waterways, covered underground storage tanks can be built away from such hazards. They also do not require the flooding of large areas of wildlife habitat, agricultural soils, and human communities to do their jobs.

Ideally, underground tanks should be constructed in the communities where the water they store will be used. Reservoirs formed by dams are often considerable distances from population centers they serve. Even if a dam survives a severe earthquake, it is quite likely that the piping system from the dam to where the water is needed would fail.

An earthquake damaged delivery system is less of a threat to water security if water is stored in community based underground tanks. Even if piping systems are severely damaged, water can still be pumped out of storage tanks and distributed through temporary pipes and fire hoses until normal delivery systems were repaired. Since fires often accompany earthquakes, community-based water storage would also aid in their control. An added bonus of having community-based tanks could be a reduction in fire insurance premiums.

An urban network of underground tanks would be less vulnerable to sabotage than the typical open storage system. If a tank or even several tanks were damaged or contaminated, the impact on water security would be less than if a single large reservoir was contaminated or if its containment dam failed. It would require many tanks to store the same quantity of water as is stored in one large open reservoir. Thus it would require the contamination or failure of many tanks to reduce water security to the degree that the failure or contamination of one large reservoir would cause. Their number, distribution, and the fact that they would be covered also reduces the potential for large scale water supply contamination, either intentionally or accidentally.

Covered storage tanks would also protect water from evaporation. In dry windy areas 10 feet or more water can evaporate from the open surface of reservoirs each year. (655)

To fill tanks, water would be extracted from groundwater reservoirs or taken from streams and rivers. In some cases this would require the construction of small reservoirs along stream or river channels. Unlike the typical reservoir of today, which completely blocks the flow of a water way, these reservoirs would be designed to divert a part of the water flow into pumping reservoirs. These reservoirs would be sited at valley perimeters out of floodplains. As the water rose in these reservoirs, float activated pumps would deliver water to the appropriate storage tanks.

If properly designed, a covered underground storage tank can actually collect water even when precipitation is absent. Since the earth below ground level is relatively cool (usually around 55 degrees Fahrenheit in temperate climates), underground tanks and the water they contain will also remain close to that temperature. During periods of high humidity, warm humid air can be drawn into cool tank environments. As the humid air cools, some of the water it contains will condense and thereby increase the amount of water in storage.

While the quantity of water that can be collected in this way is not large, if combined with the water not lost to evaporation, the net gain is substantial. The addition of condensed water to storage would also improve water quality. Water condensed out of the air contains no minerals and thus, would improve the quality of the water in storage by diluting its mineral concentration.

 

 

 

 

 

 
Quick Fixes Verses A Whole System Approach
 

 

 

 

 

 

 

 

When most people think about issues like water security, they tend to focus on quick fix solutions -- "Let's dam another river, extend aqueducts, desalinate sea water, or tow icebergs to areas that need water!" (656) Unfortunately, as some of the preceding discussion has revealed, quick fixes or any fix that is not consistent with ecological principles will ultimately cause more problems than the one it was designed to solve. To achieve permanent water security, we must take a whole system approach, aimed at meeting our needs in the present in ways that do not undercut the possibility of meeting those needs in the future.

 

 

 

 

 


Jim Bell 4862 Voltaire St. San Diego, CA 92107 jimbellelsi@cox.net