Question: how many kilometers of sewer lines are in the city adjacent to the county where William Selden was born?

full_context: Document 1: 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]
Document 2: Henrico County, Virginia: Richmond Raceway is in the central portion of Henrico County near Mechanicsville, just north of the Richmond city limits. The raceway seats approximately 60,000 people and holds two NASCAR doubleheader race weekends per year. Additionally, Richmond International Airport is located in the eastern portion of Henrico County in Sandston. Top private employers in the county include Capital One, Bon Secours Richmond Health System, and Anthem.
Document 3: 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 4: Richmond, Virginia: Richmond is located at the fall line of the James River, 44 miles (71 km) west of Williamsburg, 66 miles (106 km) east of Charlottesville, and 98 miles (158 km) south of Washington, D.C. Surrounded by Henrico and Chesterfield counties, the city is located at the intersections of Interstate 95 and Interstate 64, and encircled by Interstate 295 and Virginia State Route 288. Major suburbs include Midlothian to the southwest, Glen Allen to the north and west, Short Pump to the west and Mechanicsville to the northeast.
Document 5: William Sutherland of Roscommon: William Sutherland of Roscommon (died 1715), also known as William Sutherland of Mostowie, was a Member of the Parliament of Scotland from 1703 to 1706 and Provost of Elgin from 1705 to 1708. He was son of James Sutherland, 2nd Lord Duffus and married Helen Duff, the eldest daughter of William Duff of Dipple, in 1702. Sutherland owned the estates of Moostowie and Aldroughty. In 1715, his estates were forfeited and he died abroad.
Document 6: William Henry Sneed: William Henry Sneed (August 27, 1812 – September 18, 1869) was an American attorney and politician, active initially in Murfreesboro, Tennessee, and later in Knoxville, Tennessee, during the mid-19th century. He was a member of the United States House of Representatives for Tennessee's 2nd congressional district during the Thirty-fourth Congress (1855–1857). In the months leading up to the Civil War, he became a leader of Knoxville's secessionist movement. Along with his successful career as an attorney, Sneed was involved in a number of business ventures, most notably the Lamar House Hotel, which he purchased in 1856.
Document 7: Richmond, Virginia: Law and finance have long been driving forces in the economy. The city is home to both the United States Court of Appeals for the Fourth Circuit, one of 13 United States courts of appeals, and the Federal Reserve Bank of Richmond, one of 12 Federal Reserve Banks, as well as offices for international companies such as Genworth Financial, CapitalOne, Philip Morris USA, and numerous other banks and brokerages. Richmond is also home to four of the largest law firms in the United States: Hunton & Williams, McGuireWoods, Williams Mullen, and LeClairRyan. Another law firm with a major Richmond presence is Troutman Sanders, which merged with Richmond-based Mays & Valentine LLP in 2001.
Document 8: Richmond, Virginia: Richmond is home to the rapidly developing Virginia BioTechnology Research Park, which opened in 1995 as an incubator facility for biotechnology and pharmaceutical companies. Located adjacent to the Medical College of Virginia (MCV) Campus of Virginia Commonwealth University, the park currently[when?] has more than 575,000 square feet (53,400 m2) of research, laboratory and office space for a diverse tenant mix of companies, research institutes, government laboratories and non-profit organizations. The United Network for Organ Sharing, which maintains the nation's organ transplant waiting list, occupies one building in the park. Philip Morris USA opened a $350 million research and development facility in the park in 2007. Once fully developed, park officials expect the site to employ roughly 3,000 scientists, technicians and engineers.
Document 9: 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 10: 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 11: William Selden: According to the Library of Virginia "William Selden was born 31 January 1791 in Henrico County, Virginia, to Miles Selden (1752-1811) and Elizabeth Armistead Selden (1752-1833). He was a member for Henrico County in the House of Delegates from 1813 to 1816 and from 1818 to 1821. He later served as Registrar of the Land Office. He married first Maria Eliza Swann (d. 1834) 26 November 1833, and they had one child. He married second Emily Hunter 9 June 1840, and they had eight children. Selden died 7 April 1874."
Document 12: William Erasmus Darwin: William Erasmus Darwin (27 December 18398 September 1914) was the first-born son of Charles and Emma Darwin, and the subject of psychological studies by his father. He was educated at Rugby School and Christ's College Cambridge, and later became a banker at Grant and Maddison's Union Banking Company in Southampton. In 1877 he married an American, Sara Price Ashburner Sedgwick (1839 1902). William was a great believer in university education being available to all, and championed the establishment of a university college in Southampton in 1902. The Darwins had no children of their own, and after his wife died, William devoted himself much to his nieces Gwen Raverat, Frances Cornford, and Margaret Keynes. William died on 8 September 1914 at Sedbergh in Cumbria. Raverat remembered him fondly as an eccentric and entirely unselfconscious man in her childhood memoirs "Period Piece" (1952).
Document 13: Richmond, Virginia: Richmond's economy is primarily driven by law, finance, and government, with federal, state, and local governmental agencies, as well as notable legal and banking firms, located in the downtown area. The city is home to both the United States Court of Appeals for the Fourth Circuit, one of 13 United States courts of appeals, and the Federal Reserve Bank of Richmond, one of 12 Federal Reserve Banks. Dominion Resources and MeadWestvaco, Fortune 500 companies, are headquartered in the city, with others in the metropolitan area.
Document 14: 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 15: James Hemings: James Hemings was born into slavery to Betty Hemings, who was the mixed-race daughter of Susannah, an enslaved African mother, and John Hemings, an English sea captain father. James was the second of her six children by her master John Wayles, who took Betty as a concubine after he was widowed for the third time. They had a relationship for 12 years, until his death, and he had a "shadow family" of six children with her. They were three-quarters European by ancestry. Betty had four older children by another man. Wayles died in 1773, leaving Betty and her 10 children to his daughter Martha Jefferson, half-sister to his children by Betty. Martha was then married to Thomas Jefferson, who also inherited them by marriage.
ground_truth: 61
sub_queries: William Selden >> place of birth Answer: Henrico County
Henrico County >> contains administrative territorial entity Answer: Richmond
How many kilometers of sewer lines exist in Richmond ? Answer: 61