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The Water System Part 1 By Michael Hackleman 1999 PDF

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Preview The Water System Part 1 By Michael Hackleman 1999

By Michael Hackleman (This is the first of a two-part series) U rban-dwellers rarely concern themselves with a water system. Getting water in a home or an apartment is usu- ally a phone call, some paperwork, and a monthly bill away. In this case, the water is simply turned on by the local water company. Or it’s already on, and only the name is changed for billing purposes. Rural dwellers may experience a similar process if the habitat is located in a water district, or a water system has already been developed and is fully operational. What awaits the proud owner of an undeveloped piece of land? If you’ve got utility electricity available, the local chamber of commerce will prob- ably point you at the local well drilling company. Thereafter, you need have no more to do with the process of developing a water system than writing checks for the hardware and labor. If the raw land lies too far beyond the utility grid, you will go through the throes of information hunting and a myriad of confusing decisions that may or may not result in a satisfactory water system. Left out in all of these scenarios is any real thought process that will result in a well designed water system. There are functions, processes, and materials in every system. Today, where utility power is available, there is a distinct prejudice toward the demand system, i.e., one using a sub- mersible pump. Once informed, many people will choose a store system, i.e., one using a piston pump and tank. Which is better and why? What sets the well-designed water system apart from others? Ease of use? Versatility? Functionalism? Efficient use of water and energy? The hallmark of a well-designed sys- tem is simple: it cannot be improved upon. You might find its equal but you can’t find its better. The lifeblood of a water system is the water itself. If it is to sustain you and perform the uses you will put it to, the water source must be carefully selected lest it become a source of concern. Water found in nature is “wild.” Transforming it into a form that will satisfactorily do the things we ask of it requires energy. This is the system’s heart. The system’s ener- gy source must also be selected so that the two, water and energy, merge in a hard-working symbiotic partnership that will demonstrate again and again how wise it was to expend the effort toward this end. Let’s look at sources of water, sources of energy, and the components involved in processing water itself. SOURCES OF WATER There are many potential sources of water for use in the rural water system (Fig. 1). Among the more promising sources are streams, springs, ponds, July/August 1999 Backwoods Home Magazine 9 FIGURE 1 There are many potential sources of water. and wells. It is even possible to collect the falling rain. Access is everything. Right off, some of these potential sources may be eliminated from the list; you either have them or you don’t. Some sources can only be listed as “probables,” par- ticularly if there’s no visual evidence of their presence. The extremes are interesting. It would be just as rare to find a piece of property that boasted all of these sources as one where none of them existed. So it’s safe to start with the assumption that there is at least one source available to any piece of land and a strong possibility of more than one. Each source of water is unique. But if it is to find a place as the source of water for a water system, it must pass a test. It’s not difficult to list some of the questions we would be likely to ask of it. However, let’s first look at some of the characteristics of each source that both define it and help dis- tinguish it from the other sources. Rivers and streams: Rivers and streams represent a good source of water. Streams tend to vary more in flow rates, helping shed immediate rainfall, whereas rivers typically dis- play a delayed runoff of rain and are fed by a seasonal release of water locked in snowcaps or glaciers. All rivers have their birth as streams and creeks, so size is the basic differ- ence between a stream and a river. The sheer number of streams needed to supply one river indicates the high- er probability of finding a stream on a piece of land than a river. Springs: Springs are magical water flows from the ground, in a trickle or a copious flow of unusual clarity and purity. The actual source of the water varies. It may be the reemer- gence of a stream that has gone under- ground. Quite often a seasonal stream is only a portion of an underground run of water that, because of sheer capacity, sometimes shows itself aboveground as overflow. Springs may also be the result of a tear in the fabric of the water table itself, when internal pressure “bleeds off” the excess water. In particularly dry regions, the water in some springs may come from a very great depth. Lakes and ponds: The flow of water in a river or stream may be tem- porarily interrupted by large depres- sions in the ground which must be filled before the journey is again resumed. If it’s a big depression, we call it a lake; a smaller one is simply a pond. Sometimes a lake or, more frequent- ly, a pond is not supplied just by a stream or river. In fact, it may receive a major portion of its water from a spring. There are a number of ways to determine whether this is the case. If a pond is one of several water sources available to you, you may want to defer some decisions until you’ve pos- itively established the pond’s true source of water. Shallow wells: So far the dis- cussion has centered on natural water sources (although it is possible to build a lake or pond). However, if the water is not so readily accessible, a shallow well is one way to get at it, particularly if you know it is just below ground level. And while a shal- low well can be dug with machinery, it also can be hand dug. Traditionally, a shallow well may be 3 to 4 feet in diameter (Fig. 2). Because of the extreme danger to the digger in the event of a cave-in, these wells are limited to a maximum depth of 25 to 30 feet. Deep well: A deep well may be needed to reach groundwater. The range extends, for our purposes, from 25 feet to several hundreds of feet. Wells to several thousands of feet are not uncommon, but at the going rate few private individuals could afford to drill to such depths. The diameter of the hole that’s drilled to reach water is as varied as the depths to which one might need to drill to reach water. Naturally, the larger the hole, the higher the cost. But while small and large holes alike can reach water, the difficulty of extracting it (or housing the equip- ment designed to do this) increases significantly as the diameter drops below 6 inches. A compromise is indi- cated. It will be easier to find the opti- mum diameter once a water-extraction system is selected and size of the equipment available from local well- drillers is determined. Rainfall: Precipitation initially supplies the water for streams, rivers, lakes, ponds, springs, and wells. However, in whatever form—rain, snow, hail, sleet, or con- densation—rainfall is a potential source of water in itself. A clue to the means whereby rainfall can be tapped as a water source is sup- plied by nature. Streams and rivers, at the persistent urging of gravity, chan- nel the runoff from rainfall to lower elevations. Damming one of these sluices is, in effect, a means of rainfall collection. Another crude but inexpen- sive way to duplicate this effect is to July/August 1999 Backwoods Home Magazine 10 A shallow well may be dug with a backhoe. FIGURE 2 continued on page 13 dig a trench across a slope in the path of runoff, terminating the lower side in some type of storage. Serious collectors of rainfall are both practical and innovative, merely channeling rain shed by rooftops and their edge-mounted gutters into stor- age such as a cistern for later use. A surprisingly small amount of roof area will yield thousands of gallons of very clean water each year (Fig. 3). Rainfall measurements are taken by a number of agencies and records extend back for fifty years or more. Using these figures and allowing for a 20 to 30 percent loss due to splashing, overflow, and initial washdown of the rooftop, a remarkably accurate deter- mination of capacity may be assessed for any rooftop. Combining sources: There is a strong tendency in the United States for individuals to establish one strong source of water at a particular site and, damn the expense, set up the entire water system around it. This approach to water-system design is understand- able. However, many areas don’t experience such hardy water sources. And where they exist, the supply diminishes as populations expand and the use of water increases. Given the diminishing availability of pure water sources, the notion of “one source, one system” becomes both foolish and dangerous. It’s foolish because most situations have access to at least two water sources. It’s danger- ous because single-source systems are inherently vulnerable to the possibili- ty, however remote, that the source will dry up. Even a temporary stop- page can be trouble for a system that has made no provisions for such an event. Evaluating sources Each source of water has inherent qualities and limitations. Decide which is an advantage or disadvantage to you. Access: Access implies on-site presence. While much may be hidden from the eyes, if you don’t have it, you don’t have it. Relative to streams, ponds, and springs, a walk of the land will quickly reveal whether they’re there or not. If they are, list them as probables. The same goes for any source that is intermittent, such as sea- sonal streams. However, don’t con- fuse “don’t know” with “definitely not.” For most properties, the evalua- tion of this single criterion access will cut the list of possible water sources in half. Ease of development: On a scale of one to ten, make a prelimi- nary evaluation of the relative ease or difficulty of developing any probable water sources. In a way, this is an availability rating. If you can walk right over and scoop it up, it gets a high rating. If you don’t know, give it a question mark. Water and the law: Access to, and availability of, water is not equiv- alent to the legal right to use it. Just because a stream flows through your property does not mean that you can take any of it for any purpose you wish. In some instances it may be per- missible to take the water for house- hold use or for a small garden, while other usages such as irrigation of fields, watering of livestock, and power production may be prohibited. In some places, this may even apply to a spring that starts on your own but that passes over the property line. Legal use of water is defined as “riparian,” “appropriative,” or both. The first acknowledges the need to share water, and the second is “first come, first served.” It’s beyond the scope of this article to cover all of the possibilities in sufficient detail. But it’s up to you to fend for yourself. Water rights are not always clearly designated in the property deed, nor are they automatically part of the title search that commences once a proper- ty is in escrow. Little wonder, then, that people buy a piece of land only to discover sometime after the sale that their right to the water on their land is restricted or prohibited. For this rea- son, any property that has an unusual abundance of water that has not been developed should be treated as suspect in this matter. If you want to make some use of the water, make its legal use part of your conditions of sale, or keep on looking. Contamination: All surface waters are subject to pollution. Airborne pollutants brought down by the rain. Fecal matter from animal stock, camper owners, and improperly installed and maintained septic sys- tems. Minerals washed from tailings (the material left over from mining operations). Logging. Roads. Landscaping projects. And others. The probability of contamination is higher with each passing mile. Lakes and ponds are in the same predicament as the rivers and streams that feed them. However, unlike their nomadic cousins, their still waters are not always able to pass the problem on downstream somewhere. Instead, the suspended material precipitates and coats the bottom. Left undisturbed, the polluted material is quickly covered by other suspended material. July/August 1999 Backwoods Home Magazine 13 Minimum annual rainfall (inches) Water yield (sq. ft.)* (gallons) FIGURE 3: Net yield of water for cisterns per square foot of catchment area 10 4.2 15 6.3 20 8.3 25 10.5 30 12.5 35 14.6 40 16.7 45 18.8 50 20.8 * Adjusted for 30% water loss due to leakage, splash, roof washdown, and evaporation Rooftop rain collection is used worldwide. However, if the inrush of water feed- ing the pond or lake normally stirs up the sedimentary layers, watch out. Those who harvest the rich silt from seasonal ponds should take note. They may get much more than they bargain for. Springs and wells are least affected by contamination, even though their water percolates down through the soil from the surface. The soil itself is an excellent filter. In fact, the water doesn’t have to go very far at all. With some soil types, a few feet is suffi- cient to remove most of the contami- nants. For this reason, water from springs and wells is some of the purest available. However, this water is also exposed to mineral deposits, and other substances. Their concentration in the water may exceed levels acceptable for human consumption. Collected rainfall is also quite pure. The first few minutes of rainfall should purge the air through which it passes of contaminants. Furthermore, this same water will flush the actual collection system (a rooftop?) of any other particulates. But, while this source altogether bypasses the type of exposure experienced by streams, rivers, ponds, lakes, springs, and wells, it is also devoid of the benefi- cial trace elements found in these sources. If used as the only source of drinking water, its sterility actually could be unhealthful. These are relative indicators. Until proved otherwise, water from any source should be considered suspect and tested. If need be, it should be treated for the presence and relative concentration of a host of elements, minerals, pollutants, and bacteria. Any source of water exposed to the open air may also be contaminated by nuclear fallout. Whether it’s from test- ing or an actual war or the failure of a nearby nuclear power plant, the effect is the same. Naturally, rivers, lakes, streams, and ponds are easily contami- nated by fallout. Again, springs and wells are the least affected. However, a big part of this is “cover.” An open spring box, open storage of well water, and a rooftop system for rain- fall collection defeats the natural protection of these sources from contamination. Proximity to usage: A poten- tial water source should be rated according to its distance from the point where the water is needed. This evaluation assumes that the building site has already been established. If it has not, pick some “possibilities” and evaluate the potential sources accord- ingly. Precise distances are not required. A simple comparison between two or more sources is suffi- cient for now. In the final analysis, it’s conceivable that developing a less accessible source closer at hand may be preferable to the cost or relative difficulty of transporting water from a readily available water source. Elevation: The elevation of each water source relative to the usage site should be noted. It takes energy to move water. If the water can move itself via gravity flow, all the better. July/August 1999 Backwoods Home Magazine 14 M M easuring capacity is rarely a difficult task. However, such a mea- surement represents an instantaneous reading. Measure it later—by the hour, day, week, month, half year, or year—and you’re likely to come up with as many different values as the actual number of readings taken. Why? Simply stated, capacity varies. Rainfall, snowpack, seasons, drought, or unusually wet periods influence capacity. So do earth- quakes, evaporation, seepage, increased usage, and higher popula- tion densities. No water source is exempt from the effects of some of these conditions. Minor fluctuations are of no concern. The variance in the readings one will obtain from any one source over a period of time, however, is evidence enough that we’re not talking about insignifi- cant differences. If we took the readings at regular intervals over the span of a year, we’d know both the minimum and maximum values of capacity. A fail- safe tactic then, is to build your sys- tem based on the lowest figure obtained. Another tack—basing your system on a capacity figure halfway between the minimum and maxi- mum readings—makes more sense, but it introduces an element of risk. Voluntary conservation may be needed during the drier portions of the year. A saner and safer course might be to select a rating closer to the minimum and between one fourth and one third the maximum. It is impractical to wait long enough to take readings over a peri- od of a year just to obtain figures and then extrapolate a reasonable design capacity. A faster means of obtaining a sound answer is to dis- cover exactly what factors are responsible for the variance in the capacity of any water source. This has a fourfold effect. One, it helps select the best time to take the reading. Two, it indicates what can affect the accuracy of the reading. Three, it permits adjustment of the reading to a figure useful in system design. And four, it indicates what can affect the specific source(s) you use. This assures a quick response to a crisis and implementation of conservation techniques or alternate water sources. It beats waiting until the effect is felt and it’s too late. A fish has no exclusive claim to being stranded high and dry. SIDEBAR A: MEASURING A WATER SOURCE’S CAPACITY So, higher ratings go to sources that are higher than the usage site. This is relative. A high-elevation water source that is too far away, is not in line of sight, or is traversed with gul- lies or other inhospitable terrain is less appealing. Approximate these eleva- tions above or below the level of the usage site. Capacity: Any water source has a capacity. This refers to the maximum amount of water it will deliver under any condition. It’s usually described in some convenient term such as gal- lons per minute (gpm) or gallons per hour (gph). Depending on the source in question, there is always some means of approximating or measuring the source’s capacity (Sidebar A). Let’s look at the factors that may affect the capacity of the water source. This includes the measurement, usage, evaporation, seasonal variation, rain- fall, and other factors. The measurement. Always choose as large a time frame as per- missible—anything timed in seconds, or portions thereof, includes a larger degree of possible error than something timed for half a minute or more. Then, no matter what pains you took to do it right, repeat the measure- ment. An accurate reading is a repeatable one. Usage. A variance in capacity may be attributable to a variance in the use of the water. How many times have you heard someone claim that there’s less water available during the sum- mer than in the middle of winter? There are other factors that affect this, but one that’s frequently forgotten is that there’s a greater need for water in the summer for cool showers, the watering of orchards and gardens and such than in winter. This doesn’t con- stitute a real change in capacity, but it sure feels like one. An influx of new residents in the immediate vicinity will inevitably bring about a greater usage of water, decreasing the supply of some sources. Or there may be very little change. Even a new well or spring development nearby will not necessar- ily tap your own supply. At worst, the water table may drop and a stream dry up. Depending on the types of water rights in your area, you may or may not be able to do something about it. More drilled wells in the immediate area will inevitably lower the water table further, and your well could dry up. Unfortunately, subsurface water is not nearly so well protected in a legal sense as streams or rivers may be. The difficulty of proving that any specific well is responsible for the loss of oth- ers is obvious. If you are still in the developing stage, this might be a case against a spring or well development. Is there a potential for a lot of new wells or a few high-consuming wells (as for industry or business) in the vicinity in the years ahead? Naturally, the small- er the parcel of land, the higher the probability of some effect from a neighboring well near the property line. Sitting snugly in the middle of even a piddling forty acres is buffer enough against interference in most instances. Evaporation. Water left standing in the open will be sucked up by the air as water vapor. This is called evap- oration. The rate at which water evap- orates depends on the dryness of the air, the temperature of the ambient air and water, the amount of water exposed (the surface area), and the amount of air movement (wind speed). If this is the source for a water system or the storage for water taken from other sources, evaporation must be taken into account in estimating its capacity (Sidebar B). Water standing in spring boxes, wells, covered tanks, or cisterns (closed reservoirs) also experiences some losses due to evaporation. However, since less air is in contact with the water under these conditions, smaller losses are incurred. Spring and stream-fed ponds and reservoirs may show little capacity variance due to evaporation losses, as these may be offset by input. On the other hand, ponds or reservoirs that are filled by a seasonal stream must hold their own against losses other than normal use, such as evaporation or seepage. In these cases, evaporation becomes a critical factor. There’s little one can do about evap- oration from an existing pond. A new pond, on the other hand, can be designed to minimize losses. Start with the pond’s shape. It should be relatively deep in proportion to its sur- face area. Retaining the volume but halving the surface area will halve the evaporation losses. A second tactic is to site the pond out of the direct rays of the sun. Taking advantage of shade trees or natural shading from hills will help. Know the sun’s path through the sky during the summer months. If natural shade is not available, build it. If it’s too expensive to shade the reservoir July/August 1999 Backwoods Home Magazine 15 UU nder the worst possible conditions—very dry air, lots of wind, a hot and sunny day—the amount of water lost to evaporation is actually measurable. To see this, find a pond and stick a ruler in the mud. Take a reading in the morning of a high-evaporation day and another that evening. I’ve measured a ¼-inch loss in one day strictly from evaporation. (This test assumes that no other water is being taken from the pond.) With a big pond, it adds up quickly. For example, with a circular pond 50 feet across, a ¼-inch drop adds up to 306 gallons lost per day. That’s 2,140 gallons a week—in one month, 9200 gallons sucked up by evaporation. It doesn’t take many months to dry up a pond at that rate. SIDEBAR B: LOSSES DUE TO EVAPORATION altogether, erect a structure that will shade the water for at least a portion of the day. If nothing else, knowing the effect of evaporation should indicate the futility in simply damming up a sec- tion of a creek in the merry belief that this is an automatic guarantee of water through the hot summer. And, as the levels sink, you won’t be lured into an assumption that it’s “seeping away” and throw more money into solving that problem. Of course, you could be losing water both ways—to evapora- tion and seepage—but each inflicts losses that no conservation techniques will dent. Seasonal variation. A dry creekbed in the middle of summer may be a raging stream during winter. Measuring the level of water in a well will invariably lead to higher readings in the dead of winter than those taken in the fall. That comes as no surprise to most people. Winter may bring cold and misery, but it also brings precipi- tation. In the form of sleet, rain, hail, or snow, it’s still water. And as the water makes its way over and into the land, the water table rises, the creeks begin to flow or flow more profusely, and ponds fill. Any measurement of capacity must take into account the season in which it’s taken. A water system designed around a reading taken at the end of summer is never going to want for water. A system based on a reading in the spring of the year may find itself in trouble by summer’s end. How much difference will exist between the two readings? Unfortunately, it’s too situational to generalize. The capacity rating used for system design will probably be something below the average of these two readings. Fortunately, we don’t always have to be exact with these figures. It is helpful to have some numbers for sys- tem design, but we must not lose sight of the fact that capacity does vary. Inevitably that means that sometimes there will be too much water and at other times too little. A good system can easily handle the rare instances where there’s too little source capaci- ty. It’s a versatile system that is able to make use of the instances where there’s “extra” water. One limitation of end-of-summer capacity measurements is that the source may have just temporarily run out of water. An otherwise good source of water may be hidden. Don’t be put off by a really low reading. Besides the fact that it’s the reliability of the source that’s important, take some consolation in the fact that the reading you’ve obtained probably rep- resents the lowest it will ever be. Rainfall. While winter is normal- ly characterized by an abundance of water and summer by a lack of it, rain- fall occurs in varying amounts throughout the year. So rainfall at other than seasonal times is a bonus and its absence a penalty to some water sources. Few water sources will note a measurable difference in capac- ity from a light rain, even if it’s over a period of several days. If the rain is heavy, however brief it may be, the ground may not absorb it rapidly enough and runoff will occur. In this event, even seasonal streams may flow and ponds will fill. This event should be treated solely as a bonus to a system—if it’s able to capture it. This bonus will permit an extra ration to the garden and a long shower for yourself. However, no system should be designed around such a chance occurrence. Accordingly, whenever a measure- ment of capacity is taken after any such freak event, the reading must be adjusted accordingly. Cloudbursts and heavy rainfall runoff may be considered for their water potential, in addition to a sys- tem’s own reliable water source, if they occur often but aren’t predictable enough to depend on. Here the gain must be weighed against the cost of establishing some means of collection, and possibly storage, of the runoff. Since heavy runoff is characterized by turbidity (suspended particles like silt, organic materials, etc.), a secondary storage setup is recommended, even if it’s only temporary. This recognizes that while filters to eliminate water turbidity do exist, the best overall means of controlling this condition is to let the water “pool.” Once immobi- lized, the suspended particles will simply settle to the bottom of the holding tank. Springs and wells are unlikely to experience any immediate increase in capacity due to rainfall. If the rainfall is short-lived and comes down hard, there will be no increase, since the water will escape along the surface. A long, slow rainfall will raise the water table, but it will take time for the water to reach it through the earth. Any measurements from either a spring or well that are taken a few days to a few weeks after a long, steady rainfall may affect a capacity measurement. The reading should be adjusted accordingly. Other factors. Other factors will affect either capacity or our measure- ment of it—earth tremors, leaks in the system, etc. The intermittent nature of any wildly fluctuating water source motivates people to seek other, more reliable sources. But in the cost/bene- fit ratio taking into account such fac- tors as dollars, time, skills, knowl- edge, reliability, simplicity don’t rule out extensive or occasional use of variable capacity sources. No source is a guaranteed, long-term thing. Fortunately, anything that might affect capacity only influences some of the potential water sources at any given site. Therefore a multiple source water supply is preferable to one seemingly strong source. If nothing else, permit options in the final design and sketch out a few details for con- necting up to an alternative source should you need to. A preplanned July/August 1999 Backwoods Home Magazine 16 continued on page 19 course of action in an emergency is a whole lot better than merely reacting to the situation. Specific uses: We’d all prefer to have grade AA water or better, but with the sources available to us that may not be possible. Water purifica- tion beyond some token filtering is costly, complex, and difficult to main- tain, and should always be avoided. Too often a water source that’s only slightly tainted is crossed off the list in favor of one that delivers purer water at a significantly higher cost in devel- opment, transportation, or complexity. A large part of the difficulty in this thought stems from a tradition lump- ing all of our water uses together as needful of the same level of water purity. That is, we demand drinking water quality in the toilet! Understandably, we will want a high level of purity in water used for drink- ing, cooking, dishwashing, bathing, and some gardening. Other needs—agricultural, watering stock animals, washing clothes, treating sewage, watering lawns, washing cars, storage in case of fire, and so on, do not require perfect water. The two groups overlap and may even be sepa- rated into other “shades” of water purity. Only the ready availability of pure water has prevented more exten- sive implementation of “graywater” systems. Other than the cultural stigma attached to graywater use, the main objection to multiple uses of water has been the need for duplication of pipe runs and sufficient planning to ensure that the various levels of water do not unwittingly merge. For existing sys- tems requiring retrofits, the objection is valid. However, for new systems the cost of the extra material and designwork is very competitive with the higher need for water and the ener- gy required to pump it from supply to use. Since pure water sources are decreasing and the cost of energy is increasing, a system that favors low water use (characteristic of multiple use systems) also uses less energy. Cost: So many of us have taken water for granted so long that when it comes time to shell out some money for a water system, we’re shocked at the cost—we might be talking about thousands of dollars! Striving to keep the costs to a minimum is natural, and any system should be cost effective. However, it’s unwise to concentrate too long or heavily on cost right away. Otherwise, we end up letting this fac- tor lead us through the myriad of deci- sions, and down the line we end up paying for it in some other way. Maybe the ultimate cost will be too high in intangibles—dissatisfaction, for example, or time and worry, adjustments in lifestyle, a lack of ver- satility in the system. Sometimes, though, we’re talking about hard cash repairs, refits, modifications for every little new thing that’s added to the sys- tem, extraordinary maintenance, the cost of consumable materials such as filters and chemicals, those monthly energy bills, etc. Rarely do our trou- bles stem from ignorance; too often, we know these things exist. If we had the power really to minimize them as effectively as we’re able to convince ourselves of their supposedly minimal effect, we’d have something. Good design can significantly reduce the impact of the initial cash outlay for a system. For example, an honest appraisal of what’s needed right now and what can wait until later gets things going with a reduced cash outflow. Planned “add on” always costs less than modifications that weren’t anticipated from the start. Another merit of this approach is that it permits a “weathering” of the sys- tem. Changes do occur, so the water system you design may have a differ- ent feel once you start living on your land a year from now. People change, situations change, and both affect the system. A wise course of action takes that into account. Design it, build the portion you can afford, and build in sufficient leeway for changes as they’re needed or when you will have the money. You get what you pay for. Remember: the bitterness of poor quality is remembered long after the sweetness of low cost is forgotten. ENERGY SOURCES As with anything that has weight, if we want to move water from one place to another we must use energy to do it. Individual water systems have individual energy needs. Very few are lucky enough to require “no” energy, and some are unlucky enough to require energy at every step—extrac- tion, transport, pressurization, and storage. Water that required one or more of these steps to be converted from standing water into useful form for household or farm use is said to be processed. Let’s look at the variety of energy sources that may be set to work pro- cessing water. Gravity: Whenever and wherever water is high enough to let gravity do all the work, let it. Sometimes, even when it isn’t high enough, it pays to go out of your way to give it this potential for the benefits it yields over the energy expended in the effort. More on this later. Human muscle power: Water may be processed by human power. This takes two forms. One is through use of the bucket, where a person scoops up the water and walks from the water source to the point of usage. At the rate most families use water today, this would prove labor inten- sive. However, the idea has some merit, and should not be rejected out- right. The initial investment is small (one bucket) and the exercise alone should keep anyone fit. Human power can also transport water through the use of a pump. The hand operated pump standard has been around for a long time, and it’s guar- anteed to give you strong arm muscles along with the water. A variation on July/August 1999 Backwoods Home Magazine 19 the theme is a pedal-powered water pump. Legs are more powerful than arms, and through suitable linkage the leg muscles may be put to work pumping water. Admittedly, for all that pedaling the scenery doesn’t change much, but at 100 gallons to the “mile,” who’s complaining? Animal power: Prior to the use of fossil fuels, physical labor beyond the capacity of the ordinary man or woman was done by beasts of burden such as horses, oxen, or goats. This is still a good possibility for pumping water wherever any of these animals have been reintroduced to the farm or homestead. However, considering the amount of feed these critters can con- sume, centering any water system totally around animal power is a doubtful possibility. Fossil fuels: Another popular energy source for processing water is fossil fuels. Initially only oil was available. Its use was limited to cen- tralized facilities where oil burning turbines drove generators, producing electricity that was, in turn, transport- ed over wires to the usage site. Once there, the electricity could power elec- tric motors that would supply the needed mechanical motion to operate pumps of various types. Fossil fuels in the guise of utility-supplied electricity are probably the number one source of energy for water systems in the U.S.A. today. High density fuels—propane, diesel, kerosene, and gasoline—derived from fossil fuels may also be purchased for engines powering onsite water processing equipment. However, the cost and noise factors usually limit this usage to backup systems for use only during emergencies when the primary system isn’t functioning. Waterpower: Moving water is also an energy source, whether it’s a river or a waterfall. Either way, this energy may be captured by a variety of novel mechanical or electrical devices. In turn, these will pump a portion of this water (or water from another water source) to places far away or higher up anywhere the water would not flow of its own accord. The simplest device available is the hydraulic ram (Fig. 4), which uses the energy of water to pump a small por- tion of the water to a higher point. Theoretically, the hydraulic ram will pump l/10 of the water 10 times as high as the waterfall, 1/100 of the water 100 times as high, and so on. Pump inefficiencies reduce this amount somewhat. If a landowner has access to a river but either has no legal right to use any of its water or chooses not to, the dual-acting hydraulic ram is useful. It uses the energy of the river’s water to pump water from another source such as a spring or well to the appropriate place. Waterwheels and turbines will also pump water directly. More often, however, they are connected to other devices that supply mechanical energy or, in the case of generators, electrical energy. Natural gas: The decomposition of organic materials under certain environmental conditions produces natural gas. At the utility company level, this gas is often processed to produce propane, which has a higher energy yield per cubic foot than natur- al gas and is easier to liquefy. Back on the farm, natural gas may be produced from animal or agricul- tural waste in a digester. Methane (CH4) is the desired end product, but it is produced in company with other gases and substances. In this mix, it’s called bio-gas. Detectable amounts of bio-gas may be produced from a remarkably small amount of organic material. For application in a water system, sufficient bio-gas must be produced to power a small internal combustion engine. This in turn can operate a water-pumping mechanism or produce the electricity to power a motor that will drive a pump. This requires an enormous amount of animal or agricultural waste. Nevertheless, where the right condi- tions exist, the production of bio-gas is a viable alternative to on-site energy sources for small, engine-driven water pumping functions. Wind power: Another major source of energy for water processing systems is the wind. Here, one of sev- eral types of wind machines extracts the wind’s energy and converts it into the mechanical motion needed to work a water pump. If there’s a problem with this setup, another type of wind machine can be used to produce elec- tricity to power a motor connected to a water pump. As far back in recorded history as you’d care to go, wind has been harnessed to pump water. In some areas the wind is both constant and strong enough to guarantee water July/August 1999 Backwoods Home Magazine 20 FIGURE 4: The hydraulic ram is a water-powered water pump. processing around the clock, but this is rare. Any system that uses the wind’s energy for water extraction and transport must be equipped with suffi- cient storage to satisfy demand during periods of low or no wind. In the 1800s there was a definite need for water pumping in very remote areas for livestock and agricul- ture. To meet this need, private com- panies developed wind machines that were simple, rugged, and virtually maintenance-free. Even the later intro- duction of electrically powered motors and oil, kerosene, or gasoline engines could not stem this industry. After the initial investment, there is no further operational cost with a wind machine. Closer to the farmhouse, these wind machines did yield to the high capaci- ty electrical pumps. The mere pres- ence of the old towers and windma- chines today is proof enough that the farmer or rancher wasn’t inclined to let them go altogether. Even in disuse, these reliable machines are hard to part with. Selecting energy source Each potential energy source—grav- ity, muscle power (human or animal), fossil fuels, natural gas, water, or wind —should be evaluated in terms of energy needs, reliability, availability, access, independence, complexity, and cost (initial and ongoing). If you have no prejudice in the matter, this becomes a straightforward process of elimination, followed by a simple choice if more than one source emerges unscathed. If you do have preferences (most of us do), this process may help you select a sec- ondary, or backup, energy source. Is that necessary? Judge for yourself. Energy needs: A prime factor in selecting an energy source is its ability to handle our system’s needs in processing water. Irrespective of how much that amounts to, you want to keep this to a minimum. A system’s need for energy is ongoing. Since energy in any form costs something, both dollars and “sense” dictate using as little as possible. Now is as good a time as any to introduce the Concept of TANSTAAFL. That’s short for “There ain’t no such thing as a free lunch.” Don’t expect something for nothing. No energy source is free. What about gravity? True, gravity is everywhere. Yet, if the water source on the property is too low relative to the usage site, you can’t put gravity to work unless you first expend some other form of energy to lift the water high enough for gravity to take over. If your site doesn’t permit you to take direct advantage of gravitational ener- gy, one fact emerges: you have a lot more energy sources to choose from if you can keep the system’s energy requirements very low. Water pump- ing wind machines, for example, will suffice even in areas of very low wind. They’re designed to operate at low wind speeds. This advantage is lost in energy intensive systems, as would be the case with muscle power, methane, and small scale waterpower developments. All too quickly, energy sources available onsite are lost in the “big energy” shuffle. Reliability: Reliability is, first and foremost, not having to worry about the system. Open a faucet and you should get water. If the storage tank is low, either it is filled automati- cally or, through a monitor, you are informed when refilling is needed. Reliability is also continuance. Everything wears out sooner or later, but frequent breakdowns are a symp- tom of a problem. Reliability doesn’t just happen. If this factor isn’t built into the system in both its design and equipment, it’s doubtful that it will be exhibited during operation. How do you design for reliability? That’s easy—follow the kiss principle: Keep It Simple, Silly! A system is no better than its smallest or weakest part. If you skimp on any aspect of the system, it’s going to get you. Reliability is increased as the num- ber of energy conversions and trans- fers involved between the prime mover (energy source) and the appli- cation decreases. Let’s compare two systems. In System A, a water pumping wind machine converts the wind’s energy to mechanical energy (rotary motion) and then into a reciprocating action (up and down motion) which, via a long rod, works the water pump. This amounts to one energy conversion and two simple energy transfers. In System B, the water system is based on a submersible pump powered with utility supplied electricity. How many steps are involved? Since most of this electricity comes from oil or coal burning power plants, the coal or oil must be found, extracted, processed, transported to the power plant, and burned. The resultant heat produces steam, which drives turbines coupled to electrical generators. The manufac- tured electricity travels through power lines to your land, where it drives an electric motor which in turn operates a pump. That’s six energy conversions and four energy transfers. Now, I ask you which system, A or B, is likely to be more reliable? Availability: Availability has a time frame. What has been available in the past and is now may not be available in the future. Many people don’t like to think about that—it smacks of doomsday—but there’s no avoiding it. The world is running out of oil, natural gas, and coal. The experts may not agree on when our supplies of these natural resources will be exhausted, but it will happen. This is the time of plenty, and chances are pretty good that it won’t happen in our lifetime. However, long before the fuels run out, the ripples of the short- age will make themselves felt. Independence: An offshoot of availability is a personal decision involving independence. However July/August 1999 Backwoods Home Magazine 21 gregarious we are, most of us would like to gain control of our individual lives. The convenience of utility sup- plied electricity, then, might be shunned for the independence to be gained by using available on-site energy sources to which no meters are attached. Independence comes when you take on the responsibility for the sys- tem—its maintenance, correct opera- tion, and at least minor repairs. Complexity: The connection between reliability and complexity has already been established. Complex systems seem easier to operate than simple ones. Why? Essentially, automation takes the burden of deci- sion making away from the human user. Given the sheer number of fac- tors at work, to choose the correct response for any given set of circum- stances requires an extensive monitor- ing and control setup. There’s nothing inherently evil about complexity. Any increase in vulnerability arising from the number of parts is easily offset if the owner/operator understands how it’s all supposed to work. Supposedly, then, it’s easy to troubleshoot and iso- late malfunctioning components. This makes the individual an integral part of the system. The alternative is to set up a simple system and retain the decision making aspect yourself. Certainly the fewer the component parts, the less there is to go wrong. I prefer this approach because it keeps me in touch with my system. A side effect of this involvement is that I’m apt to notice a problem that can be fixed before it results in a breakdown or requires the replacement of an expensive component. Cost: It’s sometimes difficult to separate the energy costs from the sys- tem costs. For example, the use of some variable, intermittent, or low yield energy source demands a provi- sion for water storage (tank, cisterns, etc.). However, there are other reasons that might prompt an individual to use a storage system. Or to install a much larger size than what’s required for simple utilization of the energy source itself. Without getting into actual dol- lars and cents, we can establish a few associations. One concerns the initial cost versus the ongoing cost. Utilizing available on-site energy sources such as wind energy and water energy seems at first prohibitively expensive. All the money is up front. By compar- ison, a utility powered submersible setup comes with a lower initial price tag. However, there’s a string attached. It all runs on specialized energy that must be purchased in monthly installments. The “string” is suddenly an umbilical cord. Water systems based on renewable (indepen- dent) energy generate their payoff in dollars saved through the years. It was an enlightening experience to rebuild my water pumping windma- chine and be told that the last time the company made a major change in the design was 1933! What does this have to do with costs? If you’re to spend hard earned dollars on equipment, it’s nice to get built-in quality, rugged- ness, and craftsmanship. Even several generations ago, the workmanship was superb. Manufacturing dollars spent on equipment of an older design go into materials. Newer equipment must pay off tooling, designwork, and advertising to inform the public that the product exists. Multiple energy sources: Just as it’s good to have more than one water source, it’s good to have more than one energy source. Any energy source or service can suffer a temporary interruption. How well the system will fare during this period is a matter of design and luck. Minimizing the “luck” part is, of course, desirable. Systems that apply all of their energy to processing water in such a way that it may thereafter assume energy-free (gravity) flow and pressurization are prepared for such eventualities. Some owners may find the price tag for this brand of security a little steep. An alternative is the system that uti- lizes two or more energy sources. While either may be interrupted at any time, the probability that they would both disappear simultaneously is mighty low. Add a third energy source and you can bet your nest egg that you’ll have at least one of the three sources operational at any given moment. Contemplating the use of two energy sources when you haven’t even picked one may seem a bit much at this point. No problem. Pick one, design the sys- tem around it, and install it. Use it that way for a while. Keep thinking about that alternative, though. Which is the right one may not really become clear until later anyway. The only important thing you should do before installing a water system is keep your options open. For example, it’s always nice to avoid duplicating any more of the equipment than is necessary. Knowing beforehand what additional source might be used will help you select equipment that may also accommodate the other energy source when (or if) it’s added. Forethought will at least identify where the systems can be joined. Even if the “mate-up” plumbing is not installed initially, you can keep this...

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