Tempe, Arizona Water Outage Today

Tempe tap water system, by the numbers

City of Tempe is the water system EPA lists for Tempe, serving about 165,000 people. Customers know it as City of Tempe Water Utilities; the name on your bill is the one to call.

Source water and treatment in Tempe

Tempe drinks surface water. City of Tempe draws it from rivers, lakes or reservoirs and treats it before it goes into the distribution system.

The outage angle. Surface water needs a treatment plant running around the clock, so a plant shutdown, a raw-water pump failure or a long power cut at the plant can lower pressure across the whole service area, not just on one street. Boil water notices are more likely to be citywide after that kind of failure than after a single main break. EPA lists 2 emergency connections to neighboring systems, which can be opened to move water across a boundary during a failure.

What causes water outages and low pressure in Tempe

These are the causes that match the record for Tempe, listed roughly in order of how much they matter here.

• Flooding and heavy rain. NOAA logged 560 flood, flash flood and heavy rain reports in Maricopa County from 2015 through 2026. High water can wash out the ground under buried pipe, flood pump stations and push treatment plants past their limits, which is why boil notices so often follow a flood.
• Summer demand. Tempe has about 139 days a year at or above 95°F and 104 at or above 100°F, and the hottest day in the record came on June 20, 2017. Lawn irrigation and cooling push demand to its yearly high, so pumps run hard, tanks drain faster than they refill and pressure sags on high ground in the evening.
• Storm-driven power loss. Thunderstorm wind, hail and tornado reports in Maricopa County number 852 since 2015. Pump stations and treatment plants that depend on Salt River Project (SRP) run on the electric grid, so a storm that downs power lines can lower water pressure even when no pipe is damaged.
• Long dry spells. The longest stretch without measurable rain since 2015 lasted 98 days, ending December 16, 2017. Dry soil shrinks and shifts around buried pipe, and breaks often cluster when the rain returns and the ground swells again.
• Younger pipe, different risks. Only 17% of occupied homes in Tempe predate 1970 (US 35.5%), so more of the network is newer plastic or ductile iron. Breaks tend to come from construction damage, pressure surges and weather rather than age.
• Construction and third-party damage. A backhoe or boring crew that hits a main is among the most common reasons a single block goes dry without warning. Utilities handle those the same way as any break: isolate, repair, flush.

How weather strains the Tempe water system

Heat, not frost, is the main weather stress on the water system in Tempe: summer demand peaks while irrigation and cooling run at full tilt.

The figures are reanalysis estimates for the center of Tempe, not readings from a single weather station, so treat them as a guide to how often each kind of weather occurs rather than as official records.

Is Tempe water safe? Boil notices and EPA record

EPA lists 2 health-based violations for City of Tempe since 2015. It also lists 13 monitoring or reporting entries that are about paperwork rather than water quality, such as a missed sample or a late report.

Most recent health-based entries:

• October 2017: A treatment technique violation It is marked resolved.
• April 2017: Drinking water above the legal limit for total trihalomethanes It is marked resolved.

When Tempe loses pressure after a break or a failed test, City of Tempe Water Utilities asks affected customers to boil water for drinking and cooking. The notice ends only after samples come back clean, which usually takes one to two days after service returns, and the Arizona Department of Environmental Quality (ADEQ) supervises the process.

Lead service lines and old plumbing in Tempe

The most recent 90th-percentile lead result filed for City of Tempe is 4.4 ppb (2024). The federal action level is 15 ppb, so that result is far from the limit.

17% of occupied homes in Tempe were built before 1970, and lead service lines and solder stayed legal until the federal ban in 1986. After any outage that disturbs the pipes, run the cold tap 30 seconds to 2 minutes before drinking, and ask City of Tempe Water Utilities about its lead service line inventory.

How long a water outage lasts in Tempe

A crew that arrives at an ordinary main break in Tempe usually needs 4 to 8 hours to isolate the pipe, dig, repair, flush and restore pressure. Large transmission mains, deep pipes and breaks under busy streets can take a day or more.

Ask City of Tempe Water Utilities for a restoration estimate when you report the outage; for large breaks it is normally posted and updated as the repair progresses.

Preparing for a long water outage in Tempe

Census figures put the typical Tempe household at about 2.4 people. At one gallon per person per day that is 7 gallons for three days or 34 gallons for a two-week supply.

• Heat: 139 days a year top 95°F here, so plan for more than the one-gallon minimum, and keep extra for pets.
• 24.1% of homes are in buildings with 20 or more units. Upper floors lose pressure first, and rooftop tanks and booster pumps depend on building power.
• 57.7% of households rent. Tell your landlord or property manager about a leak or outage right away, since the shutoff valve may be theirs.
• A standard water heater is a ready-made 40-gallon reserve. Shut off its power or gas, open a hot tap somewhere in the house, and draw from the drain valve.
• If a planned shutoff or storm is coming, fill the tub and some buckets for flushing toilets and washing; keep drinking water in clean sealed containers.

How Tempe compares with nearby water systems

Water outage pages for nearby cities

Mesa, AZ · Scottsdale, AZ · Phoenix, AZ · Tucson, AZ