Dow’s Hometown, Dow’s Contamination
Midland, Michigan is inseparable from Dow Chemical. The company was founded here in 1897, grew into one of the world’s largest chemical manufacturers here, and still maintains its global headquarters here. Midland is, in many ways, a company town — one where the company’s legacy includes both prosperity and pollution.
For over a century, Dow’s manufacturing operations discharged waste containing dioxins and furans into the Tittabawassee River, which flows through Midland and downstream through Saginaw County to the Saginaw River and eventually Lake Huron’s Saginaw Bay. Dioxins — among the most toxic chemicals known — accumulated in river sediment and floodplain soil, creating a contamination corridor that stretches for miles.
What Are Dioxins?
Dioxins are a group of chemically related compounds that are persistent environmental pollutants. They’re produced as byproducts of industrial processes including chlorine-based chemical manufacturing — exactly the kind of operations Dow conducted in Midland for decades.
The most toxic dioxin variant, 2,3,7,8-TCDD, is classified as a known human carcinogen. Health effects associated with dioxin exposure include:
- Cancer (particularly soft tissue sarcoma, non-Hodgkin lymphoma, and liver cancer)
- Chloracne and other skin disorders
- Liver damage
- Immune system suppression
- Reproductive and developmental effects
- Endocrine disruption
Dioxins don’t dissolve easily in water — they bind to soil particles and sediment. The primary exposure pathways are through contaminated soil, sediment, and consuming fish or other food from contaminated areas.
The Scope of Contamination
The Tittabawassee River floodplain contamination was publicly confirmed in 2000 when testing by the state of Michigan found dioxin levels in floodplain soil at concentrations hundreds of times above residential cleanup criteria.
Key findings:
- Dioxin levels in floodplain soil along the Tittabawassee River downstream of Midland were found at levels up to 1,000+ parts per trillion (toxic equivalents), far exceeding Michigan’s residential cleanup criterion of 90 ppt
- River sediment contained elevated dioxin concentrations for approximately 50 miles downstream of the Dow facility
- Fish tissue in the Tittabawassee and Saginaw Rivers showed dioxin levels that prompted consumption advisories
- The contamination extends into the Saginaw River and Saginaw Bay, affecting one of the Great Lakes’ most important ecosystems
- Residential properties in the floodplain — homes, yards, gardens — were contaminated with dioxin-laden soil deposited during flood events over decades
In 2020, the problem was dramatically highlighted when a dam failure upstream sent floodwaters through Midland, raising fears that contaminated sediment and soil had been redistributed across previously clean areas. Post-flood testing confirmed that the flooding did mobilize some contaminated material.
The Superfund Response
The Dow Midland/Tittabawassee River area was designated as an EPA Superfund site. The cleanup has been divided into multiple operable units:
- Dow’s Midland facility: Source control and on-site contamination
- Tittabawassee River: Sediment removal and floodplain soil remediation from Midland downstream
- Saginaw River and Bay: Assessment and potential remediation of downstream contamination
Dow (now Dow Inc., following corporate restructuring) has been conducting the cleanup under EPA oversight. The work includes:
- Excavation and removal of contaminated floodplain soil from residential and recreational properties
- Sediment remediation in priority river reaches
- Long-term monitoring of dioxin levels in water, sediment, fish, and soil
- Institutional controls including fish consumption advisories and floodplain land use restrictions
The cleanup is expected to take decades and cost hundreds of millions of dollars.
Midland’s Drinking Water
Despite the dioxin contamination in the river and floodplain, Midland’s municipal drinking water has generally met federal standards. Here’s why:
- The city’s water treatment plant draws from the Tittabawassee River but treats the water through a conventional process that removes most particulate-bound contaminants
- Dioxins bind to sediment particles, so they’re largely removed during the treatment process
- The city monitors for dioxins and other contaminants in finished water
However, the situation isn’t completely reassuring:
- Dioxins are toxic at extremely low concentrations, and there’s no federal MCL specifically for dioxins in drinking water
- The 2020 flood raised questions about whether the treatment plant’s intake was exposed to higher-than-normal dioxin loads during the flooding
- Residents on private wells in the floodplain area face a different risk profile than those on municipal water
The 2020 Dam Failures
In May 2020, the Edenville and Sanford Dams upstream of Midland failed during heavy rains, sending catastrophic flooding through the city. The floodwaters inundated neighborhoods, destroyed homes, and raised urgent questions about contamination:
- Did the flooding redistribute dioxin-contaminated sediment from the river and floodplain?
- Were previously clean areas now contaminated?
- Was the Superfund cleanup progress undone?
Post-flood testing found that while some contaminated material was mobilized, the overall impact on the cleanup was less severe than initially feared. But the event highlighted the inherent vulnerability of communities living near long-term contamination sites — especially in an era of more frequent extreme weather events.
What Midland Residents Should Know
- Municipal water is treated and monitored. Check the city’s annual Consumer Confidence Report for current water quality data.
- Don’t eat fish from the Tittabawassee or Saginaw Rivers without checking the current Michigan fish consumption advisories. Dioxin contamination in fish tissue remains a concern.
- Floodplain residents should be aware of soil contamination risks, especially in gardens and areas where children play. If your property is in the floodplain and hasn’t been assessed, contact the Michigan EGLE or EPA.
- Private well users near the river should have their water tested. While dioxins primarily bind to soil, other contaminants from the Dow facility — including solvents and other industrial chemicals — may affect groundwater.
If you’re concerned about your water quality in Midland or the Tittabawassee River corridor, a certified water treatment professional can test your water and recommend appropriate treatment for your specific situation.
Sources: EPA Superfund program (Dow Chemical Co./Tittabawassee River), Michigan Department of Environment, Great Lakes, and Energy (EGLE), Michigan Department of Health and Human Services, ATSDR