Water Knowledge

Metering and Private Water Management

Your water meter is where public water management by the District ends and your private management begins. The meter to your house is located near the street curb in front of your house or in the alley/easement behind the house. It is a rectangular box in the ground with a removable cover. The meter tells the District how much water flows through it, meaning how much water you use. The public service line from the water main to the meter, the meter itself, and the meter box are owned by the District. You are then responsible for the private service line after the meter to your house and any other private outdoor pipes on your property.

If you need to turn off the water to your house, please turn it off at the water shut-off valve at the house, NOT at the water meter. If you need the water turned off to your whole property, please call the District at (520) 575-8100 and we will turn off the water at the meter.

There are many useful resources for water management to address a wide range of maintenance and conservation strategies from water provider organizations in Southern Arizona:

  • Water Use It Wisely – Conservation strategies and public awareness of wise water usage in our desert for both adults and children.
  • Smart Home Water Guide – Sponsored by Arizona Municipal Water Users Association (AMWUA) in the Phoenix area. An excellent resource to assist homeowners in reading their meters, outdoor and indoor leak inspections, isolation strategies of the private system to address leaks, and water efficiency in our desert environment.

Disaster Preparation

How to Winterize your Pipes
Take a quick survey and look for any water pipes exposed to the elements. Typically, this would include the main pipe entering the house (located with the water shut-off valve), irrigation lines, backflow preventers and, if applicable, swamp cooler lines and swimming pool lines.

Any water line that is exposed to the elements, where water does not constantly move, is a potential candidate for freezing. The exposed lines can be protected with pipe insulation, which is a low-cost solution that can be purchased at local hardware stores.

What if it’s too late and your pipes freeze?
During an extended or severe cold spell, your pipes can freeze, even if you take all the proper precautions. If you think you know where the freeze occurred and you want to try thawing it yourself, the easiest tool to use is a hair dryer. DO NOT under any circumstances use an open flame. Using the hair dryer, wave the warm air back and forth along the pipe. DO NOT heat only one spot on the pipe, as this can cause it to burst. If you don’t have a hair dryer, you can wrap the frozen section with rags or towels and pour hot water over them. It’s messy, but it works. Be careful when heating the pipe. It may already be broken and just not leaking because the water is frozen. When you thaw it out, the water could come gushing out. Be ready to run for the main water shut-off valve if necessary.

How can I be prepared for natural/man-made disasters?
You cannot predict when, or if, natural or man-made disasters will occur, but you can do some simple planning and take some simple precautions in the effect they do occur. The Federal Emergency Management Agency (FEMA) under the Department of Homeland Security (DHS) has prepared guidelines for preparing a kit, having a plan for your family or business, and remaining informed in case such events occur.

For more information visit READY.GOV

Where can I get information on how to make water safe to drink in an emergency?
In the event of emergencies, where the safety of food and the water supply may come into doubt, the Center for Disease Control (CDC) has established guidelines and provides instructions for ensuring safe food and what to do to ensure safe drinking water.

For more information about “Food, Water, Sanitation, and Hygiene Information for Use Before and After a Disaster or Emergency” at the CDC website.

Water Fundamentals

What is Water?

Water is the building block of all life and an essential component of all living things. Known by its popular chemical formula, H2O, each molecule of water is made from two hydrogen atoms and one oxygen atom, forming a covalent-bonded, polar molecule. As a molecule, water has very unique properties, especially in how it expands as it freezes (about 9%), which is why ice floats on water, and why lakes freeze from the top down. The only other substances that expand when frozen are silicon, bismuth, antimony, and gallium. For its size of molecule, water can also form an unusually large number of intermolecular hydrogen bonds that lead to a strong attraction between water molecules, evident in water’s high surface tension and capillary forces. These intermolecular bonds give water the second highest specific heat capacity of any substance (ammonia is the highest), and a very high heat of vaporization, both of which allows water to moderate the climate of planet Earth by buffering large fluctuations in temperature. 

Many know or are not surprised that water covers over 70% of the Earth’s surface, and that oceans comprise 97% of all water. However many are surprised to find out the fresh water in rivers, lakes, and ponds comprise only 0.6% of the total water on earth, or that only an estimated 1.6% of all water is contained within underground aquifers. The remainder is contained in frozen glaciers and polar ice caps. Depending upon someone’s size, between 55% and 78% of a human body is comprised of water, and water has very unique chemical properties that make life possible and sustainable. There is a reason humans can only survive a few days in a hot desert without water, because so much of how our bodies work and regulate temperature is reliant on being properly hydrated. For this, and many other reasons, clean drinking water should always be considered a precious resource for all living things.

What is the water cycle?

The water cycle is the continuous process water goes through on earth shown in the diagram below. Surface water, primarily from oceans or other freshwater storage, undergoes “evaporation” into the atmosphere. Along with evaporation is “transpiration” (or evapotranspiration), where water vapor is also released from plants and animals. Also, “sublimation” occurs when frozen water vaporizes without first melting. All this water vapor is stored in the atmosphere until finally undergoing condensation when the air becomes sufficiently saturated, forms into droplets, and falls to the ground by way of “precipitation” in rain, snow, etc. Frozen precipitation is generally stored until it seasonally melts and joins other liquid water in streams, rivers, and other surface runoff as it makes its way back to the oceans or other freshwater storage areas. A portion of this surface runoff also sinks into underground aquifers, or groundwater, that also is eventually released into the oceans. The cycle then begins all over again.

Why does the water come out when I turn on the faucet?

Water comes out of your faucet because it is stored under pressure in the water pipes. Pressure is defined as a force applied to a given area. If you hold your finger over a straw and try to blow through the straw, you can feel the pressure building behind your finger. If you release your finger, air is allowed to flow out of the straw. The same applies to water within pipes when a faucet is opened.

Where does the water come from when I turn on the faucet?
For customers of Metro Water, water coming out of your faucet first comes from a well, typically from hundreds of feet below ground, pumped up to the surface and usually stored in very large tanks called “reservoirs”. This water is then either pumped or drops in elevation through underground pipes in the streets to each neighborhood. Each house then connects to these bigger pipes call “mains” with smaller pipes called “service lines”. The water then enters the plumbing in each house, and to each fixture such as a faucet.

How do you know how much water people use?

Metro Water knows how much water each customer uses with what is called a “meter”. This device is placed along the service line extending from the water main to where the water enters a home (typically at the property line), and records the volume of water that passes through it. Readings are taken each month to determine how much water a customer used since the reading the previous month.