
That desire led NRDC and a host of other environmental groups to file an appeal yesterday challenging the renewed Clean Water Act permits issued in December by Illinois EPA to the Metropolitan Water Reclamation District for its “big three” sewage treatment plants in the Chicago River system – Stickney, Calumet, and O’Brien (formerly Northside).
The permits are, sadly, yet another in a string of head-in-the-sand responses we’ve been seeing to one of the most serious problems facing our waterways, in Chicago and nationwide: the choking mats of algae being fueled by phosphorus and nitrogen dumped into the water by sewage treatment plants and other sources. While the MWRD permits do at least take the modest step of implementing a numeric limit on discharges of phosphorus – the pollutant most responsible for algal blooms in the Chicago region and downstream – that limit is not even close to strong enough to make a serious dent in the problem. Federal and state law required that Illinois EPA establish a permit limit on phosphorus through scientific analysis, but the Agency didn’t do that. Or do anything that even resembled that. Sad to say, the evident basis for phosphorus limit is that it’s the limit MWRD told the Agency it wanted.

US EPA has not done nearly enough to address the problem, which is why we recently sued and won concerning its failure to take action. However, the federal Agency at least took initiative to set some rough numeric benchmarks awhile back for the level of phosphorus that will protect against excessive algal and plant growth. Agency scientists surveyed the nation’s waters and came up with a maximum level of phosphorus that could be present in the water in various “ecoregions” without fueling algal blooms. Here in the Chicago area, that level was found to be .076 milligrams per liter (mg/L) in rivers and streams. Meanwhile, Wisconsin – which is far ahead of Illinois and most other states in this regard – did its own analysis and set a phosphorus level of 0.1 mg/L for its rivers and .075 for smaller streams, meaning that all of its dischargers (including sewage treatment plants) will have to have permit limits that ensure that very low level is not exceeded.
When Illinois EPA first proposed the new MWRD permits back in 2009 – yes, governments move at about that speed when they have a problem they don’t want to deal with – US EPA, to its credit, told Illinois EPA that it had better comply with legal requirements to come up with a science-based phosphorus limit that would prevent algal blooms.
Alas, however, that demand turned out to be empty saber rattling. Illinois EPA more or less let MWRD pick the limit it wanted, and US EPA let them get away with it. That limit – 1.0 mg/L – is ten times higher than the level established for rivers in Wisconsin (which is pretty similar to what would be right for neighboring Illinois), as well as the .076 mg/L criterion recommended for the region by US EPA.

North Shore Channel photo (top) by Susan D. Lannin
Lower Des Plaines River photo (middle) by Cynthia Skrukrud, Ph.D
I-55 Bridge phote (bottom) by Alan Burton, Ph.D