Is Detroit, MI Tap Water Safe to Drink?

Where Does Detroit Get Its Water?

Detroit's drinking water comes from the Great Lakes system, drawn and treated by the Great Lakes Water Authority (GLWA) before being distributed through the city's own water system. The primary utility serving Detroit residents is the City of Detroit water system, which purchases treated water from GLWA and delivers it across Wayne County.

GLWA operates two major treatment plants that serve the Detroit area: the Springwells Water Treatment Plant and the Water Works Park Water Treatment Plant. Detroit's system also includes a Northeast Water Treatment Plant and a Southwest Water Treatment Plant, providing additional capacity and redundancy for the region.

Several neighboring communities, including Hamtramck, Highland Park, Redford Township, and River Rouge, receive water through interconnections with Detroit's distribution network. All of these systems draw from the same GLWA-treated source water, meaning the underlying water quality is largely consistent across the area.

How Is Detroit Tap Water Treated?

The water goes through a multi-step treatment process before reaching your tap. This includes conventional treatment steps such as coagulation and filtration to remove particles and sediment. Ozone is also used as part of the treatment process, which helps break down organic compounds and improves taste and odor.

Disinfection uses free chlorine, which is maintained through distribution to protect against microbial contamination between the plant and your home. A low-level ultraviolet (UV) treatment step is also applied, providing an additional layer of protection against pathogens without adding chemical byproducts.

The combination of ozone, UV, and free chlorine represents a layered disinfection approach. This multi-barrier strategy is common among large surface water systems and helps ensure microbiological safety even as water travels through miles of distribution pipe.

What's in Detroit Tap Water?

The most widely detected substances in Detroit's recent EPA testing were PFAS compounds, a family of synthetic chemicals, and lithium, a naturally occurring element. Lithium was detected across all 29 monitored ZIP codes at levels up to 9 micrograms per liter. There is currently no enforceable federal maximum for lithium in drinking water; this figure is compared against a non-regulatory health reference level, and no ZIPs exceeded that benchmark.

Among the PFAS compounds detected, PFTrDA was found at a maximum of 0.007 micrograms per liter, exactly at EPA's drinking water standard for that specific compound, but not above it. Other PFAS including 6:2 FTS, 8:2 FTS, and PFBA were each detected at or below 0.005 micrograms per liter. None of these exceeded their respective guidelines, and zero ZIP codes were flagged as above any guideline.

PFAS compounds are a broad class of chemicals historically used in industrial processes, firefighting foam, and consumer products. They can enter source water through industrial discharge or runoff. The Great Lakes region has faced scrutiny over PFAS contamination in recent years, which is why national testing programs have prioritized monitoring these compounds in municipal water supplies.

Health Risk Profile for Detroit

For most Detroit residents, current tap water poses a low immediate health risk based on the available data. All detected contaminants, including PFAS compounds and lithium, were measured at or below their respective EPA guidelines or non-regulatory screening benchmarks. No ZIP code in the monitoring dataset exceeded any guideline threshold.

Sensitive groups should still pay attention. Infants, pregnant individuals, and people who are immunocompromised may be more vulnerable to even low-level PFAS exposure over time. PFAS compounds are associated with potential effects on the immune system, thyroid function, and development, though the health science continues to evolve. For these households, a certified filter adds a practical layer of protection.

For PFAS concerns, look for a filter certified to NSF/ANSI 58 (reverse osmosis) or NSF/ANSI P473 (covers PFOA and PFOS specifically). NSF/ANSI is an independent, third-party certification that confirms a filter actually performs as labeled, so look for that mark on the packaging or the manufacturer's product page. Point-of-use filters installed at the kitchen tap are generally more practical and effective than whole-house systems for PFAS removal.

Because lithium has no enforceable federal drinking-water limit, its presence at these levels does not constitute a regulatory violation. EPA's health reference level is the benchmark used here, and Detroit's water did not exceed it. Research on long-term low-level lithium exposure from drinking water is still developing, and the EPA has not set a maximum contaminant level for this substance.