Fighting the war against phosphorous

The Chicago River is the single largest contributor to the Gulf of Mexico “dead zone,” but recent recovery efforts seek to reduce dangerous levels of phosphorous making its way south.
The Chicago River is the single largest contributor to the Gulf of Mexico “dead zone,” but recent recovery efforts seek to reduce dangerous levels of phosphorous making its way south.

Almost a year after the settlement between environmental groups and the Metropolitan Water Reclamation District of Greater Chicago, progress is inching forward in reducing dangerous levels of phosphorous in the Chicago River.

By Morgan Levey
Medill Reports

It’s common knowledge amongst environmentalists that phosphorus is a harmful nutrient in bodies of water, making them uninhabitable for marine life by spurring algae growth and choking oxygen levels. It’s particularly destructive in waterways that flow out of cities, where highly polluted effluent spreads downstream, contaminating tributaries and entering larger bodies of water.

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Chicago sits nearly 800 miles away from the Gulf of Mexico, yet phosphorus from the Chicago River has a damaging reach and historically has been the single largest contributor to what scientists call the “dead zone,” an area in the Gulf roughly the size of New Jersey where fish can’t survive. And closer to home, phosphorous has been detrimental to the water quality of the lower Des Plaines and Illinois rivers.

That’s why in January 2017, after six years of litigation between local environmental groups and the Metropolitan Water Reclamation District of Greater Chicago (MWRD), a settlement was reached to prioritize the determination of what constitutes a healthy phosphorus level in the Chicago River. Now a year after the agreement was brokered, the process of redefining permit levels is proving to be slow, but the groups involved remain hopeful they are finally on the right track.

“Algae is a huge problem downstream of the plant,” said Ann Alexander, senior attorney for the Lands and Wildlife Program of the National Resource Defense Council (NRDC), of the MWRD’s treatment plant in suburban Stickney. “The point of settlement was basically to study what needs to be done in order to ultimately put together a fix to the problem, which isn’t going to happen tomorrow.”

Alexander was the attorney that negotiated the phosphorous settlement in her previous role as the NRDC’s legal advocacy director of the Midwest Program. As part of the settlement a Nutrient Oversight Committee will be established in 2018, comprising members of MWRD, the Illinois Environmental Protection Agency and a representative from the environmental groups. The committee will then hire a consultant to determine the exact levels of nutrient discharge required and make suggestions to the Illinois EPA, which will use the findings to mandate statewide permit limits.

“The expectation is that they’ll likely come up with a number by the end of next year,” Alexander said.

The initiative’s ultimate goal is to get phosphorus levels, which are measured in milligrams per liter, to a point in which they will not degrade the quality of the water that flows out of the city. While the MWRD has been operating under a self-imposed permit limit of 1 milligram per liter, Alexander said scientists agree that number needs to be closer to — if not under — 0.1 milligram per liter.

“You need to get below 0.1 [milligram per liter], which is sort of the functional limit of available technology,” said John Quail, director of watershed planning at the advocacy group Friends of the Chicago River.

An interim backstop goal of 0.5 milligram per liter by the year 2030 was written into the settlement, ensuring the process could move forward. This aligns with the MWRD’s plans to complete its Deep Tunnel project by 2029, which will manage Chicago’s stormwater runoff and make it easier to monitor the river’s water quality.

Prior to the agreement, the MWRD already employed technologies in its water treatment process to recover phosphorus from raw sewage and stormwater runoff, before it hits the river. The most productive system being utilized locally is from Ostara Nutrient Recovery Technologies. Installed at the Stickney Water Reclamation Plant, the Ostara equipment is capable of recovering phosphorus that is already dissolved in water.

”It’s allowed the largest plant in the world to achieve very low discharge numbers in terms of phosphorus,” said MWRD Executive Director David St. Pierre. And because of the Ostara process, the MWRD claims the Stickney plant is ahead of schedule, already recovering enough phosphorus to drop its discharge to 0.5 milligrams per liter.

The Ostara technology also essentially pays for itself as a revenue offset for the MWRD, according to agency officials. It turns the recovered phosphorus into non-water soluble fertilizer pellets, which are then sold as a product called Crystal Green.

“What’s nice about this product is that the nutrient value gets to the plants and it doesn’t dissolve in the water and runoff into the waterways,” St. Pierre said.

Other nutrient-recovery processes would be pricey, at a factor of ten times the current cost, according to St. Pierre. “For the taxpayers it’s an excellent way to get to the type of numbers that we need to be responsible,” he said.

Still, environmental groups insist that Ostara cannot be the only process the MWRD relies on to reduce phosphorous levels. Plus, it’s not even installed at all of the MWRD’s plants. “Ostara is only at Stickney, and that’s pretty far downstream, so we need it installed at O’Brien and Calumet also,” said John Quail of Friends of the Chicago River.

Both Quail and Alexander insist the MWRD must invest in new technologies in order to meet the levels the Illinois EPA will likely set next year. Chicago’s MWRD is by far the largest wastewater discharger in the state of Illinois, so environmental groups are hopeful that if it can make an impact on Chicago’s MWRD it can influence change statewide.

“If you can get the MWRD to agree to do something then it’s hard for somebody that’s a lot smaller to say they can’t do it,” Quail said.

Photo at top: The Chicago River is the single largest contributor to the Gulf of Mexico’s “dead zone,” but recent recovery efforts seek to reduce dangerous levels of phosphorous making its way south. (Morgan Levey/MEDILL)
Correction on 1/10/18: A previous version of this story mischaracterized the deep tunnel project as being planned/constructed by the city of Chicago. The Midwest Water Reclamation District is constructing the TARP/Deep Tunnel project slated for completion in 2029.