Royal Army College

Lesson Overview

This lesson teaches the pioneer's water task: how a force, or a population, is kept supplied with water that is safe to drink. Of all the engineering work in this course, none is more decisive or more humanitarian than this one, because water is the one thing that cannot be done without. A soldier can fight tired, hungry, cold, and wet, but a soldier without water fails fast, and a population cut off from clean water in a disaster begins to sicken and die within days. The pioneer who can find water, lift it, store it, and above all make it safe holds in their hands one of the most life-saving skills the Army possesses.

The work has two faces, and both are taught here. The first is the engineering: finding a source, judging it, lifting and moving water that is surprisingly heavy, and storing it without spoiling it. The second is the health: making doubtful water safe to drink, because clear water is not the same as clean water, and water that looks and tastes perfectly good can carry the disease that empties a camp. This lesson keeps close company with the field-health course, which treats water as the first concern of field hygiene; here we approach the same task from the engineer's side, as a thing to be found, moved, stored, and treated as a works problem, while keeping the health discipline that governs all of it.

By the end you will be able to explain why supplying clean water is a decisive engineering task; find and assess a water source and judge its likely contamination; lift and move water by simple means, reckoning with its weight; store it so it stays safe; treat doubtful water safe by the settle, filter, disinfect train, understanding why each step matters and why clear is not safe; and plan a simple water supply for a unit and for a relief task, separating drinking from washing and siting clear of contamination.

Key Terms

Source: any water a force draws on, whether surface water (stream, river, pond), ground water (well, spring, borehole), or rainwater caught off a clean surface; every field source is treated as unsafe until made safe.
Raw water: water as found, before any treatment; always handled as doubtful, however clean it looks.
Potable water: water that has been treated and kept clean, and is safe to drink; the goal of all the work in this lesson.
Contamination: anything in the water that makes it unsafe, above all the disease carried by human and animal waste, but also silt, chemicals, and fuel; the treatments here handle disease, not poison.
The treatment train: the ordered sequence that makes doubtful water safe, settle then filter to clear it, then disinfect to make it safe; the order matters, because clearing makes the disinfection that follows work.
Disinfection: destroying the disease-causing organisms in water, chiefly by boiling or by an approved chemical such as a purification tablet; the step that actually makes water safe.
Siphon: a length of tube that draws water from a higher container to a lower one over a lip, using gravity and no pump, once the flow is started; a simple, fuel-free way to move and decant water.
Lift and head: lift is the height water must be raised against gravity; head is the height it can be allowed to fall to drive a flow. Both matter because water is heavy and every metre of lift is real work.

Why water is a decisive task

Begin with why this work sits so high among the pioneer's tasks. Water is decisive because it cannot be deferred. A force can wait a day for its ammunition, its rations, or its shelter and come to no great harm; it cannot wait for its water. A person at rest in a temperate climate must drink a few litres a day, and a person labouring in heat far more, and without it they weaken within a day, fail within two or three, and become not a soldier but a casualty the force must now carry. The arithmetic is unforgiving, and it falls on the engineer who must supply the litres, day after day, in whatever conditions the task is set.

For the Royal Kaharagian Army the point is sharper still, because the Army's likeliest work is exactly the work where water has failed. When a flood, a storm, or an earthquake wrecks the ordinary supply, the thing a stricken population loses first and feels worst is clean water. The mains are broken or fouled, the wells are flooded with filth, and people crowd onto high ground or into a relief site with nothing safe to drink. This is the moment the Army is most likely to be sent into, and supplying clean water is very often the single most life-saving thing it can do there. A pioneer who can stand up a clean water point in a disaster saves more lives than almost any other field-engineering act, and a careless one can start the very outbreak the relief was meant to prevent. Hold this humanitarian core in view through everything that follows: this is not a barracks chore but, on a real task, a matter of life and death for the very people the Army exists to protect.

The task has a shape, and it is the same shape whether for a section or a settlement. Find the water; assess whether it can be made safe; lift and move it to where it is needed; treat it safe; store it without spoiling it; and issue it cleanly, keeping the drinking water apart from the washing water and both apart from the waste. Every part of this lesson is one link in that chain, and a chain is only as strong as its weakest link: a perfect source spoiled in a dirty can, or treated water drawn with a filthy hand, is as bad as no water at all.

Finding and assessing a source

The first task is to find water, and the second, which matters far more, is to judge it. Water in the field comes from four kinds of source, and each has its own character.

Surface water, the stream, river, pond, or pool, is the easiest to find and the easiest to spoil, because it lies open to everything that drains into it. A running stream is generally better than standing water, because the flow carries contamination away rather than letting it settle and breed; a still pond or a roadside pool, where filth gathers and water may have stood for weeks, is the worst of the common sources. Whatever surface water you take, take it well upstream of any place where people, animals, or waste reach the water, because what enters above you reaches you.

Ground water, from a well, a spring, or a borehole, is often the best source available, because the earth itself has filtered it on the way down. A spring rising from clean ground, or a well with a sound cover and an apron, set well back from any latrine or soakage, gives water that needs the least making safe. But ground water is not safe by virtue of being underground: a well sited too near a latrine, or one whose cover is broken and lets surface filth fall in, can be as foul as any pond.

Rainwater, caught clean off a clean surface, is among the purest field water there is, because it has fallen rather than drained. But it is only as clean as the surface it ran off and the container it fell into; rain caught off a fouled roof, or into a dirty butt, is no longer clean, and rain that has touched the ground has become surface water like any other.

To judge any source, look in four directions before you trust it, and remember that the water itself tells you least of all.

   ASSESSING A SOURCE  (judge it before you trust it)

   1. THE KIND OF SOURCE   protected ground water best; running
                           stream next; still pond or pool worst

   2. UPSTREAM / UPHILL    what drains down to here? a settlement,
                           a field of animals, a latrine, a track
                           crossing above the intake all warn you off

   3. THE GROUND AROUND    a bank churned by feet or hooves, ground
                           stained or smelling of waste, a fouled
                           margin: the source is already spoiled

   4. THE WATER ITSELF     tells you LEAST. clear water may be deadly;
                           but cloudy, oily, discoloured, or a fuel
                           or chemical smell rules a source OUT

The fourth look carries a hard limit worth fixing now. The treatments in this lesson make water safe from disease, not from poison. Water that smells of fuel, oil, or chemicals, or is suspected of any chemical contamination, is not to be treated and drunk at all, because boiling and disinfection do nothing against such hazards and may even concentrate them. Set such water aside, find another source, and treat the matter as one for qualified specialists. When in doubt, leave it.

Lifting and moving water

Once a source is found, the water must be brought to where it is needed, and here the pioneer meets a plain physical fact that governs the whole task: water is heavy. A litre of water weighs almost exactly one kilogram, which makes the reckoning easy and the consequences large. A standard jerrycan holds about twenty litres, so it weighs about twenty kilograms full, the better part of a heavy carried load in a single can. A person needing fifteen litres a day means fifteen kilograms to be lifted, carried, and issued for that one person, every day, and a relief site of a few hundred people means tonnes of water to be moved daily. Once you have this figure in your hand, the rest of the planning follows from it.

The weight of water shapes every decision. It is why you bring the people to the water, or pipe the water by gravity, far sooner than you carry it by hand any distance, because carrying water by the can is back-breaking and slow and quickly exhausts the very party you need fresh. It is why a source uphill of the point of use is worth a great deal, because water will run downhill to you for nothing, and why a source the same height or lower must be lifted, which is real and continuous work. And it is why containers and routes are planned with the full weight in mind: a footbridge, a vehicle, a hand-cart, or a shelf must each bear the loaded weight, not the empty one.

Move water by the simplest means the ground allows, and prefer gravity to muscle and muscle to nothing.

   MOVING WATER  (prefer the method that uses gravity, not your back)

   GRAVITY FLOW    source uphill -> let it run down a pipe or channel
                   to the point of use. costs nothing once set up.

   SIPHON          fill a tube, keep both ends below the source
                   surface, and water flows from the higher container
                   over the lip to the lower one, no pump needed.
                   used to decant from a settling drum without
                   stirring up the settled silt.

   SIMPLE PUMP     a hand or foot pump lifts water from a well or a
                   lower source up to a tank. needed where gravity
                   cannot help. real, repeated work.

   BY HAND         cans and buckets. the last resort over distance:
                   ~1 kg per litre, ~20 kg per full jerrycan. slow,
                   heavy, and tiring. plan to avoid it where you can.

The siphon deserves a word, because it is the pioneer's friend at the settling stage. A length of clean tube, primed full of water with both ends kept below the surface of the source container, will carry water from a higher drum to a lower one by gravity alone, with no pump and no fuel. Its great virtue at a water point is that it lets you draw the clear water off the top of a settling drum without dipping in and stirring the settled silt back up, which is exactly what you want when clearing cloudy water. Set the drawing end well above the layer of settled mud, and stop the siphon before it reaches it.

Storing water safely

Water found, moved, and treated is wasted if it is then allowed to become dirty again, and recontamination in storage is one of the commonest ways safe water turns unsafe. The discipline of storage is simple and unforgiving: clean container, kept covered, drawn without fouling.

Prepare the container with the same care as the water. Use a kind meant for water, sound and without cracks, cleaned and, if it has held anything doubtful, disinfected before treated water goes in. Never store drinking water in a container that has held fuel, oil, or any chemical, however well rinsed, because a can that smells even faintly of fuel poisons the water and the smell is your warning. Keep the container covered with a close-fitting lid or cap at all times except when drawing, so dust, dirt, insects, and dirty hands cannot reach the water, and store it out of the sun and off the bare ground so it stays cool and clean.

Draw the water without fouling it. The last few inches between the container and the cup are where most fouling happens, so draw through a tap, or with a clean dipper kept solely for the purpose and never set on the ground between uses. Never dip a personal cup, a canteen, or a hand into the stored water: a single dirty hand fouls the whole supply at a stroke, which is why a hand-washing place belongs beside every water point. Even treated water does not stay safe for ever; boiled water has no protection against fresh fouling and is best used the same day, while chemically treated water holds a little longer but is still drawn down and refreshed, not left standing for days.

Above all, keep treated water strictly apart from untreated, and drinking water apart from washing water. Mark the clean containers plainly and consistently, keep them in their own place apart from the raw-water and washing-water containers, and make the marking a habit so firm that no one stops to wonder which can is which. A single careless filling of a clean can from a dirty one undoes all the treatment at a stroke. This is the principle that runs through the whole of field water and field sanitation alike: keep the clean strictly apart from the dirty.

Purifying water: the treatment train

Now the heart of the lesson, the step that actually makes water safe. When water cannot be had from a known safe supply, and in the field it rarely can, it must be treated, and treatment is best understood not as a single act but as a short train of steps in order: settle, then filter, then disinfect. Each step prepares the next, and the order matters because clearing the water first is what makes the disinfection at the end reliable.

   THE TREATMENT TRAIN  (clear it, THEN make it safe)

   RAW WATER
      |
      v
   1. SETTLE     let it stand still in a drum until the silt and mud
                 sink to the bottom; draw the clear water off the top
                 (a siphon is ideal, so the settled mud is not stirred)
      |
      v
   2. FILTER     pass the cleared water through a filter or clean cloth
                 to take out the finer suspended matter
      |
      v
   3. DISINFECT  make it SAFE by ONE of:
                 - BOILING to a rolling boil (surest)
                 - approved purification TABLETS at the correct dose,
                   wetting the threads, full contact time
      |
      v
   POTABLE WATER     store covered and clean, kept apart from raw

   WARNING: steps 1 and 2 only make water CLEAR. clear is NOT safe.
            water is not safe until step 3, the disinfection, is done.

The first two steps clear the water, and clearing matters for two reasons. The obvious reason is that no one wants to drink mud. The real reason is that cloudy water shields the disease-causing organisms from heat and chemical alike, and uses up the disinfectant on the silt instead of on the disease, so disinfecting cloudy water is far less reliable than disinfecting clear water. To settle, let the water stand still in a container until the suspended matter sinks, then draw the clear water off the top without stirring the bed, which is exactly where the siphon earns its place. To filter, pass the settled water through a clean cloth, a sand-and-charcoal column, or a purpose-made filter to take out the finer matter the settling left behind.

But clearing is not cleaning, and this is the warning that governs the whole lesson: clear water is not safe water. Water filtered and settled until it runs perfectly clear has had its mud removed, not its disease. The water is not safe until the third step, the disinfection, is done.

Disinfection is the step that makes water safe, and there are two field methods to know. The first and surest is boiling. Bringing water to a true rolling boil, where the bubbles rise fast and break across the whole surface, not the first lazy bubbles at the side of the pot, destroys the organisms that cause water-borne disease. Boiling is the method to trust where fuel and time allow, because the heat does the work and there is no dose to get right, which is its great merit when conditions are poor. Its one weakness is that it leaves no lasting protection, so boiled water has no guard against being fouled again; cool it with the lid on and keep it covered.

The second is chemical disinfection, most simply by the purification tablets the Army issues for the purpose, and here the method is exact and the exactness is the point. Add the correct dose for the quantity of water, set by the instructions and never guessed, because a small canteen and a large can need different amounts. Cap and shake so the tablet dissolves; then loosen the cap, tip, and invert so a little treated water runs out around the threads and wets them, because the threads and lip are where untreated water hides and would recontaminate the lot at the first drink. Tighten the cap and wait the full contact time before any is drunk, allowing longer for cold or cloudy water, because cold slows the chemical and cloudiness shields the organisms. The tablets must be dry and within date; tablets gone soft or crumbled may not work at all. Chemical disinfection has one advantage over boiling: it leaves a small protective residual that goes on guarding the water and that, at a water point, can be measured to prove the treatment is holding.

A practical caution that the in-person training drives home, and that no reading can replace: do not drink field-treated water on the strength of this lesson alone. The settling, filtering, dosing, and timing are reinforced and certified in person, under qualified supervision, and the mixing of chemicals is never done unsupervised from a book. What the page gives you is the method and the reason; the hands are trained and signed off in person.

Planning a field water supply

The last task is to plan a supply, for a unit and for a relief site, and planning begins with the figure every plan rests on: how much water people need. Plan for the whole need, not only thirst, because water is wanted for drinking, for cooking, and for the washing that hygiene demands, and a planner who budgets for drinking alone will run the camp short and dirty.

   PLANNING WATER NEED  (litres per person per day; 1 litre ~ 1 kg)

   USE                  TEMPERATE, AT REST    HOT / HARD WORK
   ----------------     ------------------    ---------------
   drinking                 ~2.5 - 3 L          ~6 L or more
   cooking                  ~1 - 2 L            ~1 - 2 L
   basic washing/hygiene    ~2 - 4 L            ~2 - 6 L
   ----------------     ------------------    ---------------
   ROUGH TOTAL / HEAD       ~6 - 9 L            ~10 - 15 L+

   These are PLANNING figures, settled exactly in the practical
   training. Always plan with a MARGIN, and raise the figure for
   heat, for hard work, and (because thirst is blunted) for cold.

   WEIGHT CHECK: 200 people x 10 L = 2,000 L = ~2 TONNES of water
   to move and issue EVERY DAY. plan the lift and the route for it.

Drinking is the part that cannot be cut; cooking and washing can be trimmed in scarcity but not abandoned, because hygiene is itself a defence against the disease that thrives where people are crowded and unwashed. Hard work and heat raise the drinking need sharply, two or three times the resting figure, and cold raises it too in a way that surprises people, because thirst is blunted in the cold and under-drinking becomes a real danger. Plan generously, with a margin, and budget for the hot working day, not the cool resting one.

Then lay the supply out so that distance and slope do the guarding for you, exactly as the field-health course requires. Establish one clear, marked drinking-water point, treated and known safe, where people draw drinking and cooking water and only there. Keep the washing water separate, drawn and stored apart and never mixed with the drinking cans. And keep the latrines, the soakage, and the waste water well away from the drinking-water point and, wherever the ground allows, downhill and downstream of it, so nothing drains from the dirty toward the clean. A clear distance, not a pace or two but well back, separates any latrine or soakage from any water source and from the water point. A hand-washing place beside the drinking-water point closes the circle. The whole layout has one aim: that no person, and no rain shower, can carry filth from where it is made to where the water is drawn.

In Practice: The Water Point at the Relief Site

An earthquake has cracked the mains and fouled the wells of a small town, and within a day people are crowding onto a school playing-field on higher ground with nothing safe to drink. The Army arrives, and a pioneer corporal, an OR-3, is given the water task with a small party. The corporal works the chain in order. First, the source: the river below the field runs brown and is plainly doubtful, and a track crosses it upstream where animals are watered, so it is taken only as a last resort. But there is a borehole well at the corner of the field, set well back and uphill of where the latrines will go, its cover sound; this is chosen as the best source, because the earth has filtered it and nothing drains down to it.

Next, the weight. The corporal reckons two hundred people at ten litres a head, two tonnes a day, and decides at once that the people will come to the water rather than the water be carried to them, siting the issue point beside the well to spare the back-breaking labour of cans. A foot pump lifts the well water into a settling drum on a raised stand, so that from there it can run by gravity, and a hand party is spared.

Then the treatment train. The well water is fairly clear, so settling is brief, but the corporal settles it anyway and siphons the clear water off the top into a second drum, leaving any silt behind. It is then disinfected with the issued tablets at the correct dose for the drum's quantity, shaken, the threads of the issue cans wetted, and left the full contact time before a drop is issued. The residual is tested before the first issue and again that evening to confirm the treatment is holding, because a supply safe in the morning may not be safe by night.

Then storage and issue. One drinking-water point is established under a tarpaulin, marked plainly, drawn only by tap, with a hand-washing place beside it. The washing water, drawn separately, is kept at the far side of the field in cans marked and never mixed with the drinking cans. The latrines are dug well back and downhill of the well, a clear distance off, so nothing drains toward the source.

Downhill, a family camped by the river takes its water straight from the brown stream and falls sick within days, the children first. At the relief site, where the water was found well, lifted by pump and gravity rather than by aching backs, settled and siphoned clear, disinfected and tested, stored clean and kept strictly apart from the washing water and the latrines, no outbreak comes. The earthquake was the same for both. The difference was the engineering of water.

Check Your Understanding

Explain why supplying clean water is a decisive engineering task, and why it is among the most life-saving things the Royal Kaharagian Army is likely to do. Why can the water task not be deferred the way some others can?
Describe how you would find and assess a water source, naming the four kinds of source and the four looks you take before trusting one. Why does the lesson say the water itself tells you least, and what is the one kind of contamination the treatments here cannot handle?
Set out the treatment train in order, saying what each step does and why the order matters. Explain why "clear water is not safe water," and give the strength and the weakness of boiling against chemical disinfection. Separately, why does the weight of water at one kilogram per litre shape so much of the planning?

Reflection (write a short paragraph): This lesson insists that water is heavy, that clear is not safe, and that a single careless act, a clean can filled from a dirty one, a contact time cut short, a latrine sited too near the well, can poison many people at once, including the vulnerable people you were sent to help. Imagine you are responsible for water at a relief site after a disaster. Which step of the chain, find, lift, store, treat, issue, would be easiest to neglect when you are tired and the queue is pressing, and how might that one lapse open the route of disease for a whole camp? What does that tell you about the discipline this task demands?

Summary

Water is a decisive engineering task because it cannot be deferred: a force or a population without clean water fails within days, and for the Royal Kaharagian Army, supplying clean water in a disaster is among the most likely and most life-saving things it does, while a careless water point can start the very outbreak the relief was meant to prevent.
Find water from surface, ground, or rain sources, preferring protected ground water and running streams to standing pools, and assess every source by four looks: the kind of source, what lies upstream and uphill, the ground around it, and the water itself, which tells you least; clear water may be deadly, but a fuel or chemical smell rules a source out, because these treatments handle disease, not poison.
Reckon with the weight of water, one kilogram per litre and about twenty kilograms a full jerrycan, and move it by the simplest means: gravity flow where the source is uphill, a siphon to decant clear water off a settling drum, a simple pump where lift is needed, and carrying by hand only as a heavy last resort; bring the people to the water rather than carry it far.
Treat doubtful water by the train of settle, filter, then disinfect: settle and filter to clear it, which makes the disinfection reliable, then disinfect by boiling (surest, but leaving no protection) or by approved tablets at the correct dose, wetting the threads and waiting the full contact time; clear is not safe, and field-treated water is never drunk on the strength of the reading alone.
Store treated water in clean, covered, sound containers never tainted by fuel, draw it by tap or clean dipper and never by hand or dipped cup, and keep treated water strictly apart from untreated and drinking water apart from washing, with the clean cans plainly marked.
Plan the supply for the whole need, drinking, cooking, and hygiene together with a margin that rises for heat, hard work, and cold; establish one marked drinking-water point, keep the washing water separate, and site latrines and soakage a clear distance back and downhill of the source, so that distance and slope keep the dirty from ever reaching the clean.

Water in the Field