Duff McCartin, age 8, of Costa Mesa, California, for his question:

How does water get way up into a water tower?

A water tower may look like a big round ball, perched high on top of a sturdy pillar. Or it may look like a round sided tank propped high above the ground on a set of spindly legs. In any case, it is made to store water. But the water cannot climb up the tall tower all by itself.

You can see a water tower from afar and as you get closer it seems to stand there all alone. But it is not alone. It is connected to a water district. And a water district is a very complicated system that spreads for miles and miles through the county and then maybe through the state. Your water district brings in the water piped into your home and still more water for all the plants and factories, the hotels and motels, stores and restaurants near and far. It may be connected to the water districts of other states. It has a network of pipes and conduits, hidden underground and in the walls of buildings. Above the ground, it has dams, reservoirs and water towers.

All these parts of the water district are connected. And streams of water must be kept flowing through the whole system. When left to do as it pleases, water flows down hill. It cannot flow up a hill or climb over a mountain by itself. It needs a helping push. So the water district has pumps to push the water where we want it to go. Sometimes a city's water must be brought from a lake or a river on the .other side of a hill. The water district has built in pumps all along the way to help it up and over the hump.

Clever engineers plan the water district to supply all the water we need day and night. 0f course we use much more water during the daytime. The water is kept flowing steadily through the pipes and conduits. But sometimes we need extra supplies. So the water district has places to store them. It may have outdoor reservoirs to hold the streaming water from showers and rainy seasons. A strong dam holds the water in a man made reservoir lake. When the season is dry, valves are turned to spill the stored water through the dam. Pumps in the water district push it on its way up hill or down dale through the network of pipes and conduits.

Sometimes a water district needs to store a smaller supply of extra water. A huge lake reservoir is not needed for such a small job. So instead, they build a water tower. It may be shaped like a ball or a round tank. It may hold enough water to fill half a million or as many as 16 million milk bottles. It must be propped up high so that the water will flow down into the pipes by itself, whenever we need it. But strong pumps are needed to push the water up to be stored in the tower. No water could climb up there by itself and every water tower has at least one sturdy pump to keep it filled.

Every person uses a few quarts of water for drinking and cooking and several gallons for cleaning and bathing. This household water must be filtered and purified by the water district. But a factory may use 20 quarts of water to make a pound of steel, or 23 quarts to make a pound of man made rubber. This factory water need not be purified like water for the home. Some water towers store filtered and purified water. They are connected to pipes that lead to our homes. Other water towers store less purified water. Their pipes lead down to factories and industrial plants.