The Top 10 Biggest Wastewater Treatment Plants
The largest wastewater treatment plants around the globe.
Illustration: Justin Reynolds for ENR
1. Stickney Water Reclamation Plant, Chicago. Capacity: 1.44 billion gallons per day. Owner: Metropolitan Water Reclamation District (MWRD). The Stickney WWTP, located on 570 acres in Cicero, Illinois, southwest of Chicago, serves 2.4 million people living in Chicago and 43 suburban communities. It consists of two plants the western plant which began operating in 1930, and the southwestern plant which entered service in 1939. The Mainstream Pumping Station, the largest underground sewage pumping station in the world, lifts sewage from a deep tunnel system 300 ft underground to the plant. The sludge from the plant is dried and pelletized by Metropolitan Biosolids Management, a joint venture of Biosolids Management and Veolia Water North America Operating Services, which received a 20-year contract to design, build, own, operate and maintain the pelletization plant.
Metropolitan Water Reclamation District
2. Deer Island Sewage Treatment Plant Boston, USA. Capacity: 1.27 billion gallons per day. Owner: Massachusetts Water Resources Authority (MWRA). Driven by a federal court order in 1986 to end the discharge of 500 million gallons of poorly treated wastewater a year into Boston Harbor, the MWRA launched an 11-year, $3.6 billion program to upgrade treatment for the greater Boston area. ICF Kaiser Engineers provided construction management. Three pump stations bring the influent, which flows through grit chambers and then is routed to 48 primary treatment clarifiers. Secondary treatment is accomplished using both gravity treatment and an oxygen-activated sludge system, handled by twelve 140-ft tall, 90-ft dia egg-shaped sewage sludge digesters, the largest digesters in North America at that time. The methane produced by digestion is fed to a generator, producing 3MW of electricity. The sludge is dried further and processed into fertilizer pellets. 75 tons per day of the pellets are produced, and sold to blenders of agricultural fertilizers, landscapers, and golf courses. Following primary and secondary treatment, the wastewater undergoes disinfection to kill bacteria, first mixing it with sodium hypochlorite, followed by adding sodium bisulfite to dechlorinate the water so that the discharge will not threaten marine organisms. The plant includes both a five-mile-long, 14-ft dia underwater tunnel bringing influent from the Nut Island primary treatment plant, and a 9.5-mile long, 24-ft dia outfall tunnel to deposit the treated effluent into Massachusetts Bay. The plant handles sewage from 2.5 million people in 43 communities in the greater Boston area.
Massachusetts Water Resources Authority
3. Detroit Wastewater Treatment Plant Detroit, USA. Capacity: 930 million gallons per day. Owner: Detroit Water and Sewerage Department. The plant began operating in 1939, and only offered primary treatment at that time. The 1972 Federal Water Pollution Control Act (the Clean Water Act), which required all municipal wastewater to undergo full secondary treatment, led to the construction of aeration tanks, final clarifiers, cryogenic oxygen plants and additional sludge handling facilities at the plant. Two pumping stations lift wastewater from the interceptors into the plant. The plant incorporates a pure-oxygen activated sludge process, with covered rectangular tanks. It serves 3.5 million people living in Detroit and 76 surrounding communities in southeastern Michigan, a region of 946 square miles.
Detroit Water and Sewerage Department
4. Bailonggang Wastewater Treatment Plant Shanghai, China. Capacity: 528 million gallons per day. Owner: Shanghai Municipal Sewerage Company. The largest plant in Asia, Bailonggang first began operating in 1999, and expanded to its current capacity in 2008. Anaerobic sludge digesters were added to the plant as part of the expansion, as well as a sludge drying and disposal facility. The digestion process reduced the volume of raw sludge. A portion of the digested and dewatered sludge is treated further by thermal drying, and the remaining portion is landfilled. The dried sludge is used for non-crop applications. The biogas from the digestion process is used to operate the sludge drying plant. The expansion and upgrade project, from April 2007 to June 2008, cost $350 million and was executed by five firms: Beijing General Municipal Engineering Design & Research Institute, Shanghai General Municipal Engineering Design & Research Institute, Shanghai No. Seven Construction Co. Ltd., Shanghai No. One Municipal Engineer Co. Ltd., and China Nuclear Industry Huaxing Construction Co. Ltd. A second expansion project started in December 2009. When it is completed at the end of 2012 the plants capacity will reach 740 million gal.
Shanghai Municipal Sewerage Company
5. Stonecutters Island Sewage Treatment Works Hong Kong. Capacity: 455 million gallons per day. Owner: Hong Kong Drainage Services Department. The Stonecutters Island plant, which began operating in 2001, only offers chemically-enhanced primary treatment. It receives wastewater from the Kowloon peninsula and many parts of Hong Kong Island, about 75 percent of the catchment area of the Harbour Area Treatment Scheme (HATS), a sewage collection, treatment and disposal scheme for areas on both sides of Victoria Harbour. An expansion program, known as HATS Stage 2A, is currently under way. It includes the construction of an 880 m long, 8.5 m dia effluent tunnel and disinfection facilities aimed at intercepting and treating the sewage generated from the populated areas in the northern and southwestern parts of Hong Kong Island, which is expected to be completed in 2015. It is being built by the Chun Wo-CEC Joint Venture.
Arup
6. Hyperion Sewage Treatment Plant Los Angeles, USA. Capacity: 450 million gallons per day. Owner: City of Los Angeles Department of Public Works. The Hyperion plant began operating in 1925 as a screening plant. It underwent a $1.6 billion makeover in the 1990s, as part of a consent decree to meet state and federal standards for secondary treatment. Four influent lines feed the headworks building, where bar screens and grit chambers remove large particles. From the headworks the wastewater stream flows to four batteries of primary settling tanks. The plant incorporates a high-purity oxygen waste-activated sludge system, using a cryogenic process. Following secondary aeration, the effluent moves to secondary clarifiers and solids flow to 20 anaerobic digesters. 500 tons per day of biosolids produced by the plant are sent to Green Acres Farm in Kern County, for use as fertilizer. The farm grows crops such as wheat, oats and alfafa, which are harvested and sold as feedstock to dairies. 45 tons of biosolids per day are used to produce compost. And 7.5 million cubic feet of biogas per day is converted to electricity. The plant handles sewage from 4 million southern Californians.
City of Los Angeles Department of Public Works
7. (tie) Gabal el Asfar Wastewater Treatment Plant Cairo, Egypt. Capacity: 449 million gallons per day. Owner: Holding Company for Water and Wastewater. The Gabal el Asfar plant, located on Cairo's northeast periphery, treats wastewater for six million of the city's residents. It provides both primary treatment, including grit removal, sedimentation, clarification, chlorination and sludge thickening, and secondary treatment, including anaerobic digestion and mechanical dewatering of sludge. Methane produced by the digesters is used to generate 18.5 MW of electricity, providing 70 percent of the 26.6 MW needed to operate the plant. The plant is currently undergoing a $329 million expansion, which will increase it's capacity to 660 million gal per day when it is completed. The treated water from the plant is used to irrigate an adjoining 40-acre experimental farm that grows olives, lemons, flowers, jojoba, jetrova and cotton.
EPM Consultancy
7. (tie) Seine Aval Wastewater Treatment Plant Paris, France. Capacity: 449 million gallons per day. Owner: Syndicat Intercommunal pour lAssainissement de lAgglomeration Parisienne (SIAAP)/Greater Paris Wastewater Treatment Authority. The Seine Aval plant, the largest in Europe, is located in Acheres, 23 km northwest of Paris, and began operating in 1940. Visually the plant looks far less industrial than other wastewater plants. The rows of trees surrounding each section of the plant and the grass-covered sloping roof above the sludge treatment tanks give the site a more park-like quality. It currently treats the wastewater for three-quarters of the residents of the metropolitan area. It is undergoing a $1.3 billion modernization, which began in 2000 and is expected to be completed in 2015. During the first phase, completed in 2007, OTV France (a subsidiary of Veolia Water) built a three-story, 300 m long, 170 m wide building to hold the nitrification unit, which involves the biological oxidation of ammoniacal nitrogen into nitrates (nitrification phase), followed by the transformation of the nitrates into gaseous nitrogen (denitfrication phase). The nitrification plant uses Veolias Biostyr process, in which effluent flows through cells containing submerged polystyrene beads, to which microorganisms attach, acting as filters for removing suspended solids. OTV also incorporated their Actiflo process in the clariflocculation phase to remove phosphorus in dry weather and treat excess flows of stormwater in wet weather. During the current phase of the modernization, Degremont (a subsidiary of Suez Environnement) is increasing the plant's biofiltration capacity and adding membrane filtration capability, with Vinci and Eiffage performing additional construction tasks. Many of the improvements to the plant are responses to new requirements by the European Water Framework Directive for nitrogen and phosphorus removal. Seine Aval and the other plants in Paris have had a very positive impact on the local ecosystem; whereas only two species of fish were found in the Seine 15 years ago compared to 35 species today.
SIAAP
9. Morigasaka Water Reclamation Center Tokyo, Japan. Capacity: 406 million gallons per day. Owner: Tokyo Metropolitan Government, Bureau of Sewerage. The Morigasaka plant, Japans largest, opened in 1967, and treats the wastewater from 2.2 million of Tokyos residents. It includes the East Water Treatment Facility in Showajima, the West Water Treatment Facility in Omori, and the Nanbu Sludge Plant in Jonanjima. The East Facility has primary and secondary sedimentation tanks, and four heated digestion tanks, each 28 m dia and 19.5 m high. Methane generated in the digestion tanks is fed to a biomass power generation facility that produces 3 MW. The plant also features a micro-hydro power generation facility that produces 800,000kw.
Tokyo Metropolitan Government, Bureau of Sewerage
10. Blue Plains Advanced Wastewater Treatment Plant Washington, D.C., USA. Capacity: 370 million gallons per day. Owner: DC Water. The plant began operating in 1938 as a primary treatment facility. In 1959 it was upgraded to accommodate secondary treatment, and its capacity expanded to 240 mgd to handle wastewater from four adjoining suburban counties in Maryland and Virginia. An ambitious improvement program is currently under way. One component is a project to reduce nitrogen from about 5 mg/l to under 4 mg/l by 2015, to meet new federal standards. Eight new reactor tanks with a capacity of 40 mil gal will be added, along with a 890 mgd pump station, post-aeration facilities, new channels and conveyance structures. The program manager for this $950 million project is AECOM, and the design engineer is CH2M Hill. PC Construction Co. is doing the site preparation and some of the tankage, while Ulliman Schutte Construction will be performing the mechanical and electrical work. Because of the 153-acre sites proximity to the Potomac River, a 50-ft deep slurry wall bathtub will be built around the new denitrification tanks to avoid groundwater intrusion. Another major initiative, called the Clean Rivers Project, will reduce combined sewer overflows by digging a 4 mile-long, 23-ft dia tunnel and building a large pumping station. Traylor Skanska Jaydee Joint Venture is currently excavating a 120-ft-deep, 132-ft dia shaft, prior to beginning the tunneling in 2013. The most innovative upgrade is the Cambi thermal hydrolysis process, which will cook sludge material under high pressure and steam to generate a better class of biosolids as well as generating 13 MW of power. Blue Plains will be the first plant in North America to use the process, which is already installed at 15 plants across Europe. Camp, Dresser & McKee (CDM) is the project manager and design engineer on the biosolids project, and the CDM Constructors Inc./PC Construction Co. joint venture will build the main process train and supporting infrastructure. The combined cost of the three projects is $4 billion.
DC Water
