Question: How many kilometers of sewer lines exist in the city that contains the university where Charles Oakley was educated?

full_context: Document 1: Terry Davis (basketball): Like two similar players, Charles Oakley before him and Ben Wallace (also undrafted) after him, Davis attended Virginia Union University and made a name for himself as a hard-nosed defensive player and rebounder.
Document 2: Melbourne: Water storage and supply for Melbourne is managed by Melbourne Water, which is owned by the Victorian Government. The organisation is also responsible for management of sewerage and the major water catchments in the region as well as the Wonthaggi desalination plant and North–South Pipeline. Water is stored in a series of reservoirs located within and outside the Greater Melbourne area. The largest dam, the Thomson River Dam, located in the Victorian Alps, is capable of holding around 60% of Melbourne's water capacity, while smaller dams such as the Upper Yarra Dam, Yan Yean Reservoir, and the Cardinia Reservoir carry secondary supplies.
Document 3: Roberts Vaux: He was born in Philadelphia, Pennsylvania, the eldest son of a well-known Quaker family (Richard and Anne Roberts Vaux) and connected by marriage to another such family, the Wistars. He received his education at private schools of Philadelphia.
Document 4: Robert Lee Vann: He was born in Ahoskie, North Carolina, the son of Lucy Peoples and an unknown father. He graduated as valedictorian of Waters Training School in Winton, North Carolina, in 1901, and attended Wayland Academy and Virginia Union University in Richmond, Virginia, from 1901 to 1903. He then attended Western University of Pennsylvania, (now the University of Pittsburgh) and graduated from its law school in 1909. He passed the bar examination in 1909 and married Jessie Matthews from Gettysburg, Pennsylvania, on February 17, 1919.
Document 5: Darryl Dawkins: Darryl Dawkins (January 11, 1957 – August 27, 2015) was an American professional basketball player, most noted for his days with the National Basketball Association's Philadelphia 76ers and New Jersey Nets, although he also played briefly for the Detroit Pistons and Utah Jazz late in his career. His nickname, "Chocolate Thunder", was bestowed upon him by Stevie Wonder. He was known for his powerful dunks, which led to the NBA adopting breakaway rims due to his shattering the backboard on two occasions in 1979.
Document 6: Backboard shattering: Darryl Dawkins became famous for shattering backboards, and is credited for being the one person to cause the NBA to introduce ``breakaway rims ''. Shaquille O'Neal slam dunked so hard that he broke the supports holding two backboards during games against the New Jersey Nets and the Phoenix Suns during the 1992 -- 93 NBA season.
Document 7: Tucson, Arizona: In an effort to conserve water, Tucson is recharging groundwater supplies by running part of its share of CAP water into various open portions of local rivers to seep into their aquifer. Additional study is scheduled to determine the amount of water that is lost through evaporation from the open areas, especially during the summer. The City of Tucson already provides reclaimed water to its inhabitants, but it is only used for "applications such as irrigation, dust control, and industrial uses." These resources have been in place for more than 27 years, and deliver to over 900 locations.
Document 8: James Davis (cornerback): James Steven Davis (born June 12, 1957 in Los Angeles, California) is a former American football cornerback with the Los Angeles Raiders of the National Football League. He attended Southern University.
Document 9: Ryaverket: Ryaverket is a large sewage treatment plant in Gothenburg, Sweden. The plant is located in southern Hisingen and treats wastewater from 666,000 people in the Gothenburg region (2011).
Document 10: Duane Ferrell: Duane Ferrell was never drafted but found his way into the NBA after being signed as a free agent by the Atlanta Hawks in 1988.
Document 11: Robert Mardian: Robert Mardian went to public school in Pasadena, California followed by Columbia University, North Dakota State Teachers College, and the University of California, Los Angeles. While serving in the United States Navy he met and married Dorothy Denniss in 1946. They had three sons. Mardian was awarded a law degree from the University of Southern California in 1949. After leaving law school he went into private practice as a corporate lawyer.
Document 12: Richmond, Virginia: The wastewater treatment plant and distribution system of water mains, pumping stations and storage facilities provide water to approximately 62,000 customers in the city. There is also a wastewater treatment plant located on the south bank of the James River. This plant can treat up to 70 million gallons of water per day of sanitary sewage and stormwater before returning it to the river. The wastewater utility also operates and maintains 1,500 miles (2,400 km) of sanitary sewer and pumping stations, 38 miles (61 km) of intercepting sewer lines, and the Shockoe Retention Basin, a 44-million-gallon stormwater reservoir used during heavy rains.
Document 13: George Watts Hill: Born in New York City, the son of John Sprunt Hill and Annie Louise Watts, George Watts Hill grew up in Durham and attended the University of North Carolina at Chapel Hill where he earned a Bachelor of Science in Commerce in 1922 and law degree in 1924. At UNC he was a member of Sigma Alpha Epsilon fraternity. He married Ann Austin McCulloch on September 30, 1924. Following a ten-month honeymoon around the world, the couple made their home in Harwood Hall, the mansion that his grandfather, George Washington Watts, had built.
Document 14: Jodi Rell: Born Mary Carolyn Reavis in Norfolk, Virginia, Rell attended Old Dominion University, but left in 1967 to marry Lou Rell, a U.S. Navy pilot. The couple first moved to New Jersey, where Lou Rell took a position as a commercial airline pilot with Trans World Airlines. The family then moved to a 19th-century farmhouse in Brookfield, Connecticut in 1969. Jodi Rell later attended, but did not graduate from, Western Connecticut State University. She received honorary law doctorates from the University of Hartford in 2001 and the University of New Haven in 2004. In 2015 she received an honorary doctorate degree of humane letters from Western Connecticut State University. In her early career, she tutored and did substitute work for the Hartford Public Schools.
Document 15: Philadelphia: Historically, Philadelphia sourced its water by the Fairmount Water Works, the nation's first major urban water supply system. In 1909, Water Works was decommissioned as the city transitioned to modern sand filtration methods. Today, the Philadelphia Water Department (PWD) provides drinking water, wastewater collection, and stormwater services for Philadelphia, as well as surrounding counties. PWD draws about 57 percent of its drinking water from the Delaware River and the balance from the Schuylkill River. The public wastewater system consists of three water pollution control plants, 21 pumping stations, and about 3,657 miles of sewers. A 2007 investigation by the Environmental Protection Agency found elevated levels of Iodine-131 in the city's potable water.[citation needed] In 2012, the EPA's readings discovered that the city had the highest readings of I-131 in the nation. The city campaigned against an Associated Press report that the high levels of I-131 were the results of local gas drilling in the Upper Delaware River.[citation needed]
ground_truth: 61
sub_queries: Charles Oakley >> educated at Answer: Virginia Union University
Virginia Union University >> located in the administrative territorial entity Answer: Richmond
How many kilometers of sewer lines exist in Richmond ? Answer: 61