Iron & Rust in San Diego Water: What You Should Know

If you’ve noticed yellow water, brown spots, or a metallic taste in your tap water, you’re not alone. Across San Diego and surrounding communities, residents frequently encounter signs of iron contamination in their water supply—especially in neighborhoods with aging plumbing or private wells. While iron is a naturally occurring mineral that the body needs in small amounts, elevated levels of iron can lead to rusty water, plumbing damage, and even potential health concerns.

Let’s explore how iron particles enter San Diego’s water, the risks of iron overload, and how Culligan of San Diego can help you restore clean, safe water in your home.

Understanding the different forms of iron, their effects, and how to treat them is essential for keeping your water clean and your plumbing system running smoothly.

Red Iron
Ferric iron is an oxidized, insoluble form that is visible in water as a reddish tint. It often causes staining on fixtures and in laundry. While some water softeners can remove small amounts, iron filters—such as Culligan’s Iron-Cleer® system—are specifically designed to remove red water iron from your water supply.

Clear Iron
Ferrous iron is dissolved in water and can pass through pipes unnoticed until it oxidizes when exposed to air, causing discoloration. It often originates from groundwater sources and is best treated with a Culligan Water Softener, which uses ion exchange to remove the iron, particularly in homes with low pH levels.

Organic Iron
Organic iron forms when iron binds with organic matter like tannins, often present in shallow wells. This combination results in dark-colored water or black residue in containers. It’s more difficult to filter and typically requires customized water treatment systems.

Iron Bacteria
Iron bacteria thrive in iron-rich groundwater and leave behind dark, slimy deposits in toilet tanks and on plumbing fixtures. These bacteria also create foul odors and unpleasant tastes. While shock chlorination can help temporarily, reducing the iron content in your water is the only long-term solution.

San Diego’s water supply is sourced from a combination of imported water (from the Colorado River and Northern California via the State Water Project) and local surface water and groundwater. This supply is managed by the City of San Diego Public Utilities Department and other regional agencies. While treated to meet federal and state standards, residents may still experience orange water, cloudy water, or discolored water due to local factors such as:

Even homes connected to the municipal water supply may experience rust issues if plumbing is outdated or not properly maintained. Discolored cold water or warm water from a faucet may signal corrosion within the home’s plumbing.

In areas of San Diego County where private wells are still in use—such as parts of Ramona, Alpine, or Valley Center—iron can infiltrate well water through natural and environmental processes:

These conditions can lead to yellow water, metallic taste, and staining, especially in homes that rely on untreated or minimally treated private wells.

Rusty water causes more than just cosmetic issues. It can result in household frustration, shortened appliance lifespan, and concerns about water safety.

While the EPA classifies iron as a secondary contaminant—not typically hazardous to human health—high concentrations may contribute to indirect health risks, especially when combined with other contaminants like chlorine disinfection byproducts, arsenic, or excess sediment.

People most at risk from long-term iron exposure include:

Even when iron levels fall below the EPA’s secondary standard of 0.3 mg/L, it can still affect water’s taste, odor, and appearance. The safest way to assess your water quality is through testing by certified laboratories that can measure precise levels of iron and other contaminants.

Culligan of San Diego provides custom water treatment solutions to address the region’s specific water quality concerns, including iron and rust.

Culligan water softeners are designed to remove ferrous iron and reduce calcium buildup through ion exchange, providing soft water that protects your plumbing and improves appliance efficiency.

Sediment filters are ideal for homes dealing with orange sediment or naturally-occurring particles. Culligan also offers independent water testing performed by certified laboratory personnel to identify issues and build a personalized treatment plan.

If you’ve been dealing with rust stains, cold water discoloration, or a strange taste in your drinking water, now is the time to take action. Culligan of San Diego offers free water testing in San Diego, Chula Vista, El Cajon, La Mesa, Poway, and surrounding areas.

We’ll evaluate your iron content, calcium levels, and any potential health risks based on your specific location and plumbing conditions. Our experts will then recommend the best treatment method to deliver clean, high-quality water to every tap in your home.

Don’t let metallic-tasting or discolored water impact your daily life. Contact Culligan of San Diego today and take control of your home’s water quality.