Clean Water: Cleaning Up in Atlanta

Atlanta-area Entities are Undertaking Multiple, Major Sewer and Water Projects.

By Debra Wood

Faced with aging pipes, rapid population growth and, in the case of the city of Atlanta, a consent decree, the Atlanta region has embarked on a massive water infrastructure upgrade.

"Decades of not maintaining the system is an issue not only in Atlanta but in other cities and counties all around the United States," said Rob Hunter, commissioner of Atlanta's Department of Watershed Management. "We, as a nation, are at a point where our systems are failing because we have not invested in them."

In 1995, the Environmental Protection Agency, the Georgia Environmental Protection Division, the advocacy group Upper Chattahoochee Riverkeeper and a citizen brought suit against the city of Atlanta for multiple water-quality violations. The city settled the lawsuits with a $3.2 billion upgrade plan.

The city has funded the work through bond issues, raising customers' water and sewer rates by 45 percent, a one-cent sales tax and a commercial paper program with a $1.2 billion line of credit.

"We are now doing things to change the infrastructure for Atlanta for the next 100 years," Hunter said.

The first consent decree, which was issued in 1998, directed the city to develop and implement a plan to stop combined sewer overflows from polluting the Chattahoochee River by November 2007. One year later, the parties agreed to amend the document to eliminate violations from sanitary sewer overflows by 2014.

While undertaking the court-ordered improvements, the city decided to also invest in its drinking water system. Between Christmas 2005 and New Years Day, Atlanta experienced 13 major waterline breaks, and so it will replace drinking water lines and mains in those areas where it replaces or divides sewer lines.

The city will conduct a full evaluation and necessary rehabilitation of the sewer system. Divided into six groups, the Sewer System Evaluation Survey will inspect and repair 2,200 mi. of sanitary sewers during a 12-year period. The process involves digital closed-circuit television images, pipe lining and bursting, and open-cut rehabilitation, completed as separate contracts. Hunter said the survey was about 40 percent complete at the end of January, with the two groups most in need of repair evaluated.

Companies that performed the SSES group one included Atlanta Infrastructure Managers, a joint venture between Atlanta Utility Constructors of Decatur, Ga., Metals & Materials Engineers of Suwanee, Ga., and Q-Solutions of Tucker, Ga.; Weston Solutions of West Chester, Pa.; Compliance EnviroSystems of Atlanta; and Camken Consulting of Atlanta. All of the same companies are working on SSES group two, except for Weston Solutions.

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The city expected to release contracts for the third and fourth groups early in 2006.

The survey becomes the basis for a detailed rehabilitation plan. Contractors can watch the television footage before bidding and will know the condition of the pipes and work required. The city was preparing to release the first rehabilitation contract early in 2006.

Atlanta's Projects

Atlanta's sewer system includes separate sanitary sewers in 85 percent of its territory and a 19-sq.-mi. area with combined sanitary and stormwater pipes. The consent decree requires separation of the combination lines in the Greensferry and McDaniel CSO Basins and the Stockade sub-basin, to bring the total separated area to 90 percent.

Ruby-Collins/Reynolds/EPR, a joint venture, is performing the separation at Greensferry and Stockade. The partners include Ruby Collins of Smyrna, Ga.; Reynolds Inc. of Orleans, Ind., and EPR Environmental Pipeline Rehabilitation of Hoboken, Ga. Rockdale Pipeline of Conyers, Ga., and Integrated Municipal Services Corp. of Decatur, Ga., received the contract for the McDaniel separation.

The decree also requires construction of a deep-rock tunnel storage and treatment system that will capture overflow from the sanitary and combined sewers above and enable it to flow by gravity to treatment facilities. The plan calls for reduction of the number of overflows from more than 60 per year to an average of four annually, with those overflows screened, disinfected and dechlorinated before discharge.

The first tunnel project, the Nancy Creek Tunnel in northern Atlanta, aimed to relieve sewage backup into peoples' homes and yards. The city awarded that $150 million job to Nancy Creek Constructors, a joint venture of Obayashi Corp. of San Francisco and CJB Contracting of Atlanta.

Laser-guided tunnel-boring machines started at two different points and crews worked around the clock to complete the $150 million, 16-ft. finished diameter, 8.5-mi.-long tunnel to the R.M. Clayton Water Reclamation Center in December.

"We've had three large storm events since [the Nancy Creek Tunnel] went active, and we have had zero overflows in the basin," Hunter said.

Last July, Atlanta CSO Constructors, a joint venture of Obayashi and Massana Construction of Marietta, Ga., began work on the $286 million West Area Combined Sewer Overflow Storage Tunnel, a 8.5-mi.-long, 24-ft. finished diameter tunnel, ranging from 125 ft. to 300 ft. below ground, which will collect and carry combined sanitary and stormwater overflow to the R.M. Clayton plant.

The West Area team also will use two tunnel-boring machines to plow through the solid granite. Although work got off to a slow start, Hunter anticipates the project will finish before the Nov. 7, 2007, court deadline.

Atlantic Skanska of Atlanta is building a $47 million, 85-million-gallons-per-day combined sewer overflow plant that will process material from the West Area Tunnel. It also is scheduled for completion at the end of 2007.

Gunther-Nash of St. Louis received a $28 million contract to build a 10-million-gallon, underground storage facility at the Custer Avenue Combined Sewer Overflow Storage and Dechlorination facility, which will increase capacity to 44 million gallons.

The work, scheduled for completion in 2007, will require a 30-ft.-diameter, 120-ft.-deep, vertical construction access shaft to reach the area, then excavation of solid rock, using drill and blasting methods.

Also, the city hired Western Summit Constructors of Norcross, Ga., to complete a $26 million upgrade at the Intrenchment Creek Combined Sewer Overflow Plant, which handles flow from the Custer Avenue facility.

Atlanta also plans to start a stormwater utility to deal with maintenance of stormwater culverts, retention ponds and other facilities. Currently, if a retention pond fills with sediment, the city cannot clean it out because fees are restricted to water and sewer, with no provision for stormwater.

The city is developing options for the new services, which will add about $4 in fees to an average homeowner's monthly water bill. Then it will conduct public meetings to learn what residents want to support.

Other Area Projects

While unaffected by Atlanta's consent decrees, surrounding communities also are investing in sewer upgrades.

Crowder Construction Co. of Apex, N.C., began work in August on a $55 million expansion to increase capacity from 6 mgd to 10 million mgd at Clayton County's Northeast Water Reclamation Facility.

Crews will install a new solid handling system, switching the plant from dewatering on a belt filter press to a centrifuge that extracts more water, decreasing hauling and disposal fees, said Jim Poff, Clayton Water Reclamation Department manager.

The project, expected to finish in 2008, includes upgrading the manually operated facility to an electronic Supervisory Control and Data Acquisition System.

"The advantage is it's easier to operate and maintain the facility in compliance with a much more strict permit," Poff said. "Going from 6 to 10 MGD, we were not able to get any additional waste load into the receiving [area]. Our permit limits almost cuts in half what we had to meet."

Cobb County also has a reclamation expansion project under way. Atlantic Skanska began expanding capacity at the Northwest Water Reclamation Facility from 8 mgd to 12 mgd in 2004. The $22 million project will wrap up at the end of 2007.

At Cobb County's R.L. Sutton Water Reclamation Facility, Archer-Western Contractors of Atlanta is expanding the plant's solid-waste handling capacity and enhancing incineration and dewatering facilities. Crews will install a fluidized bed incinerator, which according to Cobb County engineers will make the plant more cost effective. This project also began in 2004 and is scheduled to finish in 2007.

Max Foote Construction of Birmingham, Ala., is building a new $16 million, 20-MGD Level Creek Pump Station, with a 2.5-million-gallon emergency wet well, for Gwinnett County. It replaces an existing 5.9 mgd pump station and will transfer raw sewage to the F. Wayne Hill Water Resources Center for treatment.

The project includes excavation of 100,000 cu. yds. of soil and rock, placement of 9,000 cu. yds. of concrete and 1,000 tons of steel reinforcement. Construction began in September and is anticipated to finish in June 2007.

"This is being done to prevent overflow into the Chattahoochee River," said Rich Schoeck, chief engineer, Gwinnett County Department of Public Utilities. "We're just keeping up with demand in the area."

Useful sources:

Clean Water Atlanta
http://www.cleanwateratlanta.org/

Upper Chattahoochee Riverkeeper
http://www.ucriverkeeper.org