Be Prepared for Life Activity Kit Three: "Water for Life"

Part 1. Getting water

DO YOU KNOW -
HOW MUCH YOUR WATER WEIGHS?

250 ml of water has a mass of 250 g,
so 1 liter of water has a mass of 1 kg.

If you used 1037 liters yesterday, then the mass of your water was 1037 kg. Almost the mass of an empty Kombi minibus!

I wonder how much water you would have used yesterday if you had to carry it home in a bucket from a tap 500 meters away? A 10 liter bucket of water has a mass of 10 kg and if you used 133 buckets of water and had to carry each one 1 kilometer you would walk 133 kilometers in a day!.

You might try to carry two buckets at a time - its still 66 kilometers - still too far! I know you would use much less water! You would discover you didn't need so much. What "water uses" would you give up? How much less water would you use in a month? In South Africa most people walking to a tap one kilometer water away use 5 liters [half a bucket] a day for all their water needs. How much better it would be to have the water close to home. Scouts can help this become a reality.

Project 1: Build your water collector Place four poles in the ground during dry weather. Tie a clean sheet over the poles when it rains and place a container at the center. Alternatively, use a plastic sheet with a small hole at the lowest point. Build a small earth reservoir lined with plastic to gather heavy down pours. Siphon the water out at the lowest point. Place a container under your roof guttering or place a wooden water diversion on the roof to direct water into a container. Do not collect the first rains for "drinking" purposes till the roof is clean.

DO YOU KNOW -
HOW TO STORE WATER IN LARGE QUANTITIES?

Project 2: Building an underground water tank Choose a site at least 50 meters away from a toilet site. If there is a large flat rock, granite dome or threshing floor nearby, dig a concave pit at the lowest point and line the pit with 3 cm of cement [1 cement: 3 sand] inserting short wire ties in the lining. The next day line the cemented pit with chicken wire using the tie ends to hold it firmly in place. Add another 3 cm of smoothed cement lining. Cover the pit with sticks and reeds / grass or build a conical roof over the tank. Use a bucket or siphon to lift water out of the tank. If there is no hard surface available - lay plastic sheeting on an up-hill slope above the tank just before the rains come. Lay the plastic over earth walls funnelling water towards the tank. Use stones to hold the plastic in position. Store the plastic away after the rains have passed or lay the plastic on the water surface to reduce evaporation. This water will need to be purified before drinking. See Project 5 BUILDING A SURFACE TANK The surface tank is filled with water collected from a roof gutter or roof diversion [see Project 1] or a protected spring [see Project 3]. There are 3 ways of building a large cement surface tank... Using a mould of 4 curved iron sheets which are bolted together using wooden spacers. Using a tube of weld mesh. Using bricks. BUILDING THE BASE Level the ground and lay a ring of bricks 2 meters in diameter as a mould. Mix concrete [1 cement: 4 stone, 2 sand], and caste a round slab 5 cm thick. Place a circle of weldmesh or chicken wire reinforcement on the wet concrete base and caste another 5 cm on top of the reinforcing. If you are using weldmesh roll a 1,8 m diameter tube, wire together and embed the ends into the wet concrete base. BUILDING THE WALLS Using the weldmesh method. Stretch a length of hessian over the framework and wire into position. Place bands of heavy gauge fence wire around the hessian-covered frame. Make a slurry of cement [1 cement : 3 sand] and flick it onto both sides of the hessian with a large brush to a thickness of 10 cm. Leave to cure overnight. Build up successive cement layers [1 cement to 4 sand] to a maximum thickness of 30 - 40 cm in all. Smooth the inside with a steel float to make it water tight. Using the mould method Bolt the four sections together, remembering to insert four spacer boards to enable the mould to be removed. Wrap chicken wire around the moulds and bind with heavy gauge fencing wire loops. Apply cement [1 cement: 3 sand] to the outside of the mould, covering the reinforcing in successive 3 x 5cm layers over 3 days. Leave 2 days to cure and remove mould. Apply 2 x 5 cm layers to the inner surface. Smooth the inner surface with a steel float. Build up the outer walls with cement [1 cement: 4 sand] to a 30 - 40 cm thickness. Using the brick method Cement [1 cement: 3 sand] a double wall of bricks enclosing a 1,5 m diameter tank. Insert the 3 pipes at this stage [see point 5]. Make sure that the vertical spaces between bricks do not line up. Allow the cement to set for 2 days. Wrap chicken netting and heavy gauge wire around the tank walls. Apply two layers of cement [1 cement : 4 sand] in two layers to both sides of the tank to a maximum thickness of 30 cm each side. Insert 3 pipes... Tap pipe 15 cm above the base. Inlet pipe, just below top of wall. Over-flow pipe, just below inlet pipe. BUILDING THE ROOF The roof keeps the water clean and reduces evaporation. Lay the empty cement bags on the ground and form a circle with a plastic pipe, with roof diameter of 2 meters. Place the reinforcing [weldmesh etc.] on top of the pipe and cut to size Place a plastic 2 litre water bottle at the point where a gutter entry hole may be needed. Caste a cement cover [1 cement : 3 sand]. Allow to cure and lift into position using planks. Seal in place with cement. Screen the entrance hole to keep leaves and rodents out of the tank. Such a tank should have a 20 to 30 year life span. BUILDING A CEMENT WATER JAR An alternative method can be used to make smaller water jars in areas where rains are more frequent. Make a large hessian bag and stuff it with dried leaves or grass or other bags. Place a 2 liter plastic water bottle in the mouth of the bag to make a convenient opening. Wet the bag and plaster it with cement [1 cement : 3 parts sand] to a thickness of 2,5 cm. Allow to cure overnight. Wrap chicken wire and fence wire around the jar before adding another 2,5 cm layer of cement. When dry, carefully remove the plastic bottle and the bag and its contents. Plaster the inside with a strong cement mixture and get it as smooth as possible with a trowel.

DO YOU KNOW -
WHAT A SPRING IS?

  Springs are usually found in mountainous or hilly country where underground water runs out at the surface. This may be under a lake or river or in a small patch of lush green vegetation. People and animals seek out these valuable water points and may contaminate the water. Springs are protected to lead their water to more convenient storage places [surface tanks] where they can be used safely.

Project 3: Protecting a spring A small concrete [1 cement: 3 sand: 4 stone] retaining wall is caste in a wooden mould around the source [eye]. Set a 40mm screened PVC pipe into the moulding 10 cm above the bed of stones inside the wall and lead to the storage tank. Insert two additional pipes into the moulding, an overflow pipe at the top, and a scour pipe in the base of stones [plug the scour pipe securely later]. The spring water drains away through the scour pipe while allowing the concrete wall to dry for three days. [If necessary build mud walls inside the concrete wall to keep it dry for the first three days]. Now remove the moulding. If the springs eye is in a bank you can caste a concrete floor over the ground below the eye. Build a back wall of loose stones to allow water to flow through them into the protected area. Make a reinforced concrete roof to fit over the spring. [See Project 2 : Building the roof]. Place the roof over the spring and seal the roof edges with bitumen [tar]. Alternatively, fill the enclosure with large stones, and cover with thick sheets of plastic. Cover the spring box with soil and fence the area off from animals. Close the scour pipe and the storage tank will fill. When enough water has been collected the supply pipe can be closed and the over-flow pipe will carry the excess water away from the protected spring. Once a year the scour pipe can be opened to clear the sediments out of the springs protective box.

Part Two: Cleaning water

© Copyright 1991 - 1994 Dr Frank Opie for the South African Scout Association