This piece was produced in partnership with Outlier Media.

In the early hours of June 26, Tammy Black was awakened by her grandson.

“Grandma,” he said. “It’s flooding in the bedroom.”

As she and her grandson hurried to salvage items from the basement, Black thought, “Oh no, not again.”

Black’s Jefferson-Chalmers home has flooded five times in the last 10 years, a combination of sewer backups from the city and river flooding due to periods of high water levels on the Great Lakes. This time, sewage-laced water nearly rose to her fusebox. 

Now, nearly three weeks after the flood, her lights are still flickering, her dining room is still stacked with storage pulled from the basement, and she’s still wondering: Why do I spend all that money on a drainage fee anyway?

For Black, the latest flood has reignited concerns about the cost of managing stormwater in the city and whether Detroit is treated equitably by the Great Lakes Water Authority, the regional water utility formed in 2014 in the wake of Detroit’s bankruptcy. GWLA leases and controls the central infrastructure of Detroit’s water and sewerage system.

At the center of both of her concerns lies the city’s combined sewer system, more than 3,000 miles of sewer lines that play a key role in the city’s flooding and water affordability issues. 

Like hundreds of older cities in the Midwest and Northeast that began developing prior to the 20th century, Detroit operates a combined sewer system that merges sewage and stormwater into a single stream of waste en route to its final destination—the Detroit wastewater treatment plant on Jefferson just west of Zug Island. At the plant, the combined sewage is treated according to federal and state regulations and discharged into the Detroit River.

The wastewater treatment plant—one of the largest in North America—is crucial to Southeast Michigan. The plant is owned by the city of Detroit but is currently leased and operated by the Great Lakes Water Authority, which officially took over operations in 2016.

During dry weather, the plant has more than enough capacity to collect and treat the region’s sewage. But during extreme wet weather events, like the torrential rains in late June, the rapid surge of stormwater into Detroit’s combined sewers can overwhelm the local and regional infrastructure, leading to critical bottlenecks that then flood the city’s streets, residents’ basements and create overflows—known as Combined Sewer Overflows (CSOs)—into the Detroit and Rouge rivers.

After the passage of the Clean Water Act in 1972, the federal EPA started to crack down on CSOs to clean up the nation’s waterways. In 1977, the federal government sued Detroit for not complying with the act. The lawsuit lasted nearly four decades, and for more than 30 years, the Detroit Water and Sewerage Department (DWSD) operated under the oversight of Judge John Feikens who had the power to settle rate disagreements between the city and the growing suburban communities that were tied into the city-owned infrastructure. Feikens had a contentious relationship with longtime Detroit Mayor Coleman Young and was nearly removed from the case in 1985 for expressing doubt in Black people’s ability to “run city governments.”  

Since the passage of the Clean Water Act, Detroit has invested $1.5 billion in CSO treatment facilities and retention basins that add capacity to the sewage system by temporarily holding and/or preliminarily treating combined sewage while other parts of the system are at capacity. 

Based on a rate settlement agreement between Detroit and the suburbs overseen by Feikens in 1999, Detroit covers 83% of the facilities’ operating costs and the debt associated with constructing them.

Managing stormwater in the era of climate change and massive floods

On the whole, the CSO facilities have drastically reduced untreated discharges into the rivers. But the late June rains are a stark reminder that in an age of climate change, extreme wet weather can still dramatically overwhelm Detroit’s sewer system—and cause combined stormwater and sewage to back up into basements and overflow into the city’s waterways. 

According to records accessed on July 13 through the Michigan Department of Environment, Great Lakes, and Energy’s (EGLE) public database, more than 2 billion gallons of “Diluted Raw Sewage” entered the Rouge and Detroit rivers on June 25. Those records are no longer available. Just seven years ago, a 2014 storm triggered nearly 3 billion gallons of CSOs into the rivers.

After the storm, Mayor Mike Duggan stressed that no sewer system could handle that amount of rain. 

“Nobody designs systems to handle two months of rain in one day,” Duggan said.

This is the central challenge that cities all across the country face in the era of climate change: There may always be a bigger storm right around the corner, and it might come sooner and more often than expected. Designing and building ever-larger retention basins, pipes and pumps is exorbitantly expensive, and such facilities may always be “behind the curve”—under-designed for what climate change has in store. 

A move toward incorporating more green stormwater infrastructure represents a shift in strategy. Instead of adding capacity to the system by building additional “gray” infrastructure (pipes, pumps and basins), green stormwater infrastructure creates or re-designs existing natural structures to soak up stormwater in the natural landscape—to avoid, delay or reduce how much water gets sent through the system.

In its latest Capital Improvement Plan, DWSD signaled an embrace of that change, stating that its goals over the next five years were to “[reduce] future investment in new CSO facilities” and “[increase] acres managed by green stormwater infrastructure.” DWSD is required to spend funds on green stormwater infrastructure to comply with its National Pollutant Discharge Elimination System (NPDES) permits, which regulate discharges. 

In an emailed comment to Planet Detroit, DWSD spokesperson Bryan Peckinpaugh wrote that DWSD “is committed to stormwater management beyond the NPDES permit requirement.” He cited the 2018 addition to the city code requiring that new developments or re-developments larger than a half acre have “onsite management of wet weather runoff instead of putting it into the city’s combined sewer system.” 

How the combined sewer system disproportionately drives up costs for Detroiters

Like many cities, however, Detroit faces the challenge of how to meaningfully fund a major overhaul in stormwater management without causing rates to drastically increase for current and future ratepayers. 

Currently, the average Detroit resident pays three-quarters of their monthly water bill to sewer and drainage services. That includes the drainage fee, adopted by the city’s Board of Water Commissioners in 2016, which charges residents and commercial and industrial properties based on the amount of impervious or hard surface on their property. 

In this sense, Detroit’s water affordability crisis is a misnomer. What drives costs for city residents is actually the combined sewer system.

The Great Lakes Water Authority charges each of its 19 wholesale customers “Sewer Shares” that aim to recover each customer’s costs of the system. Each community then adds its own local costs to these wholesale charges before billing its customers. A closer look at DWSD’s budget shows that more than half of its sewerage costs come from GLWA.

GLWA calculates these costs using a methodology that, in large part, charges each sewer district based on the volume of wastewater they contribute to the system. 

This is where Detroit’s combined sewer system disproportionately costs city ratepayers. Detroit’s combined system contributes more volume to the system than the separate sewers in many suburbs because it passes on stormwater in addition to sewage. As a result, Detroit is charged more than its suburban neighbors.

This year, GLWA will charge Detroit more than $194 million for sewerage costs, or 40% of the regional sewerage budget. This means that Detroiters, who account for just 25% of GLWA’s sewerage customers and represent only one of its 19 wholesale customers, cover an outsized proportion of the region’s shared sewer costs. 

This cost allocation is not new. GLWA inherited a system from DWSD that also charged Detroit in large part based on wastewater volume. Despite the recent appearance of the controversial DWSD drainage charge—which is not unique because cities across the country use the same method to cover stormwater costs—Detroiters have long been paying an outsized portion of the region’s sewerage costs. As the city has lost population, the burden of those costs have gotten heavier for each remaining Detroiter. As it stands today, about 675,000 Detroiters are covering the costs of a sewer system that once served 1.8 million people.

Marcus Hudson fought against this regional inequity as DWSD’s Chief Financial Officer from 2015 to 2017. He believes that the current methods of shared sewer costs, though recently simplified by GLWA, ignore the history and current reality of the region’s development pattern—namely that the suburbs were only ever able to grow by being connected to Detroit’s wastewater infrastructure. 

“You are penalizing Detroiters for staying in Detroit, first and foremost, and for rain that gets into a sewer system that’s shared by all,” Hudson said. “You should not be able to cross 8 Mile and leave your fixed costs behind. We all share in the same system.” 

In 2020, GLWA announced it had simplified how it divided up sewer costs in collaboration with its member partners. In a written statement to Planet Detroit, Suzanne Coffey, chief planning officer of GLWA, wrote that the two-year process “resulted in a simplification of what was previously a very complex method” and that the method would be reevaluated in 2029 “or earlier if circumstances develop that warrant a revisit.”

“Because the collaborative work over the last two years thoroughly considered both dry and wet weather system operations, GLWA does not believe, and is not hearing from its member partners, that the method should be [reconsidered] any earlier than 2029, as agreed upon,” Coffey wrote. 

GLWA’s new cost-sharing method went into effect this year, resulting in a nominal increase of sewer costs for Detroit.

“Rate simplification is a crock of shit,” Hudson said. “Nothing’s changed one iota.”

For residents like Tammy Black, this likely means a future where things look as they do now: Bills dominated by sewerage costs and periodic flooding.

Still, the floods are not pushing Black out.

“I love my area. I love my home. I love my neighborhood,” Black said. “We don’t want to leave our home. We need better infrastructure.”

Nina Ignaczak contributed reporting to this piece.