EPA: City's sewer plan destined to fail
Stormwater, sewage runneth over
A letter from the U.S. Environ-mental Protection Agency to the city of Atlanta, recently obtained by CL, seems to spell bad — and costly — news for the city's efforts to clean up the sewage flowing into local waterways during heavy rains.
The Sept. 21 letter states that improvements to Atlanta's combined sewer overflow facilities, in which the city has already invested hundreds of millions of dollars, are unlikely to meet water-quality standards — and thus will fail to meet requirements mandated by a judge.
The city's combined sewer overflow treatment program, which was implemented in the mid-1980s, is designed to deal with heavy rains that overwhelm the city's regular treatment plants, causing raw sewage to flood into streams and over creek banks. The mini-treatment plants are designed to strain out solids and spray the remainder with chlorine before releasing it to area streams. Six such facilities have been built.
"Based upon our initial analysis ... all the current CSO Control Facility (sic) will continue to have violations of the water quality standards," the letter says. It notes that city officials are not bound to accept EPA's assessment, but warns that — based on the city's own studies of treatment-plant discharges — current CSOs will continue to pump unacceptable levels of raw sewage into local waters during heavy rains.
The problem is decades old, but only within recent years has the city made serious efforts to remedy it. In essence, the city's sewer system is still largely based on 19th-century practices, which funnel human sewage from homes and businesses, as well as storm-water runoff from city streets, into the same sewer pipes.
When it's pouring rain, CSO treatment facilities are frequently unable to handle the massive volumes of water, and untreated sewage is released. As a consequence, pollutants such as disease-causing fecal coliform bacteria, industrial solvents and an assortment of metals present in road runoff are flushed into streams, ultimately finding their way into the Chattahoochee and other local waterways.
Over the past 10 years, Atlanta has paid nearly $19 million in fines linked to pollution discharges, spills and failures to meet construction deadlines. In a 1998 consent decree settling a federal lawsuit filed by the Upper Chattahoochee Riverkeeper, U.S. District Judge Thomas Thrash agreed that the CSO treatment plants were releasing untreated and under-treated sewage. He ordered the city to come up with a workable plan by April, 2001. The program's construction must be complete — and in compliance — by 2007.
The city has four options:
Total separation would require renovating the entire system, separating sanitary sewage from stormwater. It's the most reliable method but, at $1.4 billion, also the most costly. Still, advocates of this plan point to the heavy fines and current shortcomings as proof that the city's apparent determination to keep the CSOs is the wrong approach.
Partial separation would separate stormwater and wastewater in roughly half of the areas currently served by CSOs, while retaining combined sewers in the city's older, more densely developed areas. Although less reliable than total separation, at $1.12 billion this technique would be cheaper than total separation, and mean less disruption as streets are torn up for construction.
On-site storage and treatment would require the construction of huge underground tunnels at each CSO to store sewage until it can be treated. Estimated cost: $718 million.
Consolidated storage and treatment would require the construction of a massive underground tunnel to carry combined sewage to a new plant to be constructed on the Chattahoochee. Although the $544 million estimate is the lowest option, it's also the least likely since federal regulators have already nixed any new sewage treatment plants along the river.
A key problem with the three latter options involves the reliability of Atlanta's CSOs. Although federal guidelines allow CSOs to overflow up to four times a year, they must meet other minimum standards as well — which Atlanta's do not. Thus, even if the city's CSOs operated as expected, they'd be in violation.
And for the two storage-and-treatment options, there's an even more compelling objection: Studies indicate that those plans will provide only one-quarter of the necessary storage capacity during rainy spells.
Public works officials did not return calls seeking comment. Nor did Atlanta's chief operating officer, Larry Wallace.
But others are less reticent. Longtime separation advocate Bill Eisenhauer says it's time for everyone to face reality.
"In the past, we may have bought the notion that these CSOs would meet the permitting standards," he says. "In this case, we now have enough data to make it dead clear that they're not gonna meet those standards."