Sonoma State University

Sources of municipal water (both tap and bottled) include rivers, lakes, streams, ponds, reservoirs, springs, and wells. As water travels across land or through ground layers, it dissolves naturally-occurring minerals and, in some cases, radioactive materials, and can absorb substances from animal presence or human activity.

Potential contaminants in source water include:

• Microbial contaminants such as viruses and bacteria from sewage treatment facilities, septic systems, agricultural operations, and wildlife
• Inorganic contaminants including salts and metals that occur naturally or result from urban runoff, industrial/domestic wastewater, oil/gas production, mining, or farming
• Pesticides and herbicides from various sources including agriculture, urban stormwater runoff, and residential uses
• Organic chemical contaminants, including synthetic and volatile organic compounds from industrial processes, petroleum production, gas stations, urban runoff, and septic systems
• Radioactive contaminants that can occur naturally or result from oil/gas production and mining activities

To ensure tap water safety, the U.S. EPA and State Water Resources Control Board establish regulations limiting contaminant levels in public water systems. State Board regulations also set similar standards for bottled water to provide equivalent public health protection.

Tables 1-6 list all contaminants detected during our most recent sampling. The presence of these substances doesn't necessarily indicate a health risk. The State Board permits monitoring for certain contaminants less than annually since concentrations typically remain stable. Some data, while representative of current water quality, may be more than one year old.

Any violation of an AL, MCL, MRDL, or TT is marked with an asterisk. Additional information about violations is provided later in this report.

Common Questions About Municipal Water

Why did the City turn my water off?

1. An emergency water leak or broken water main: To complete necessary repairs, water service may be immediately interrupted for multiple households. During emergencies, we may not have time to notify all affected customers.
2. Non-payment of utility bill: If your payment becomes delinquent, the Finance Department may discontinue service. To restore service, contact Customer Service at (623) 773-7160.
3. Scheduled water leak repair: We deliver notifications to affected properties, advising when water will be temporarily shut off for maintenance. On the day of repairs, our team may provide an estimated timeframe for the outage.

What causes low water pressure?

In most service areas, water pressure typically ranges between 50-80 psi. During peak demand periods, pressure may drop to around 40 psi, which remains adequate for most household needs. To help maintain consistent system pressure, consider scheduling high-volume activities like lawn irrigation, pool filling, and car washing during off-peak hours.

Why is my water cloudy?

Milky or cloudy water usually results from air in the distribution system. The cloudiness consists of millions of tiny air bubbles that typically clear within 2-3 minutes as they rise to the surface. This condition is harmless.

Why is my water brown?

Discoloration may occur after water line repairs or hydrant flushing in your area. Sediment disturbance in water mains can cause a brownish or rusty appearance. Though unappealing, this discoloration doesn't pose health concerns and can usually be resolved by running water for several minutes until it clears.

My water sometimes has an unusual taste or smell. Is it safe?

Occasional unpleasant tastes or odors may result from naturally occurring algae in water sources. Some odors might persist even after treatment and filtration. Chlorine used for disinfection can also create distinctive but harmless tastes and smells. Other causes include bacteria growth in rarely-used water heaters or internal corrosion in water heater anodes. The most common odor issues actually originate from drain bacteria rather than the water itself.

Why is my cold water warm in summer?

This common summer phenomenon occurs because water pipes adapt to surrounding soil temperatures. During hot weather, ground temperatures increase, warming the water passing through pipes. Due to these environmental conditions, truly cold water is rarely achievable during peak summer months.

Is fluoride added to our water?

The municipal system fluoridates surface water treated at the Greenway Water Treatment Plant. Additional surface water supplied by neighboring systems is also fluoridated. Groundwater typically contains naturally occurring fluoride and isn't supplemented. As a public health agency, we monitor guidance from national health and water industry associations regarding fluoridation practices. When used at recommended levels, fluoride in municipal water is considered safe and effective for reducing tooth decay.

Why do water main breaks occur so frequently?

Most water line failures result from aging infrastructure, nearby construction vibrations, material defects, or installation issues. The utility has systematically replaced aging pipes in recent years, significantly reducing break frequency throughout the system.

What's the purpose of hydrant flushing?

Hydrant flushing is essential for maintaining water quality. High-velocity water flow helps clean and scour pipe interiors while removing accumulated sediments from the distribution system.