Question: when was the sewage system built in the city that Claire Clairmont's sister is from?

full_context: Document 1: She Walks in Beauty: It is said to have been inspired by an event in Byron's life; while at a ball, Byron met best friend Robert Wilmot, Mrs. Anne Beatrix Wilmot. She was in mourning, wearing a black dress set with spangle she was striking and he adored her and soon fell in love and she became his wife, as in the opening lines;
Document 2: Mary Shelley: Mary Shelley was born Mary Wollstonecraft Godwin in Somers Town, London, in 1797. She was the second child of the feminist philosopher, educator, and writer Mary Wollstonecraft, and the first child of the philosopher, novelist, and journalist William Godwin. Wollstonecraft died of puerperal fever shortly after Mary was born. Godwin was left to bring up Mary, along with her older half-sister, Fanny Imlay, Wollstonecraft's child by the American speculator Gilbert Imlay. A year after Wollstonecraft's death, Godwin published his "Memoirs of the Author of A Vindication of the Rights of Woman" (1798), which he intended as a sincere and compassionate tribute. However, because the "Memoirs" revealed Wollstonecraft's affairs and her illegitimate child, they were seen as shocking. Mary Godwin read these memoirs and her mother's books, and was brought up to cherish her mother's memory.
Document 3: Thoughts on the Education of Daughters: Although much of Thoughts is devoted to platitudes and advice common to all conduct books for women, a few passages anticipate Wollstonecraft's feminist arguments in A Vindication of the Rights of Woman (1792), such as her poignant description of the suffering single woman. However, several critics suggested that such passages only seem to have radical undertones in light of Wollstonecraft's later works.
Document 4: Percy Bysshe Shelley: Percy Bysshe Shelley ( ; 4 August 17928 July 1822) was one of the major English Romantic poets, who is regarded by some as among the finest lyric and philosophical poets in the English language, and one of the most influential. A radical in his poetry as well as in his political and social views, Shelley did not see fame during his lifetime, but recognition of his achievements in poetry grew steadily following his death. Shelley was a key member of a close circle of visionary poets and writers that included Lord Byron, John Keats, Leigh Hunt, Thomas Love Peacock and his own second wife, Mary Shelley, the author of "Frankenstein".
Document 5: Claire Clairmont: Clara Mary Jane Clairmont (27 April 1798 – 19 March 1879), or Claire Clairmont as she was commonly known, was the stepsister of writer Mary Shelley and the mother of Lord Byron's daughter Allegra. She is thought to be the subject of a poem by Percy Bysshe Shelley.
Document 6: London Underground: The system's first tunnels were built just below the surface, using the cut - and - cover method; later, smaller, roughly circular tunnels -- which gave rise to its nickname, the Tube -- were dug through at a deeper level. The system has 270 stations and 250 miles (400 km) of track. Despite its name, only 45% of the system is actually underground in tunnels, with much of the network in the outer environs of London being on the surface. In addition, the Underground does not cover most southern parts of Greater London, with less than 10% of the stations located south of the River Thames.
Document 7: Great Stink: The Great Stink was an event in central London in July and August 1858 during which the hot weather exacerbated the smell of untreated human waste and industrial effluent that was present on the banks of the River Thames. The problem had been mounting for some years, with an ageing and inadequate sewer system that emptied directly into the Thames. The miasma from the effluent was thought to transmit contagious diseases, and three outbreaks of cholera before the Great Stink were blamed on the ongoing problems with the river.
Document 8: She Walks in Beauty: ``She Walks in Beauty ''is a short lyrical poem in iambic tetrameter written in 1813 by Lord Byron, and is one of his most famous works.
Document 9: Allegra Byron: Clara Allegra Byron (12 January 1817 – 20 April 1822) was the illegitimate daughter of the poet George Gordon, Lord Byron and Claire Clairmont.
Document 10: Ode to the West Wind: "Ode to the West Wind" is an ode, written by Percy Bysshe Shelley in 1819 near Florence, Italy. It was originally published in 1820 by Charles in London as part of the collection "Prometheus Unbound, A Lyrical Drama in Four Acts, With Other Poems". Perhaps more than anything else, Shelley wanted his message of reform and revolution spread, and the wind becomes the trope for spreading the word of change through the poet-prophet figure. Some also believe that the poem was written in response to the loss of his son, William (born to Mary Shelley) in 1819. The ensuing pain influenced Shelley. The poem allegorises the role of the poet as the voice of change and revolution. At the time of composing this poem, Shelley without doubt had the Peterloo Massacre of August 1819 in mind. His other poems written at the same time—"The Masque of Anarchy", "Prometheus Unbound", and "England in 1819"—take up these same themes of political change, revolution, and role of the poet.
Document 11: Age of Enlightenment: Immanuel Kant (1724–1804) tried to reconcile rationalism and religious belief, individual freedom and political authority, as well as map out a view of the public sphere through private and public reason. Kant's work continued to shape German thought, and indeed all of European philosophy, well into the 20th century. Mary Wollstonecraft was one of England's earliest feminist philosophers. She argued for a society based on reason, and that women, as well as men, should be treated as rational beings. She is best known for her work A Vindication of the Rights of Woman (1791).
Document 12: The Cloud (poem): "The Cloud" is a major 1820 poem written by Percy Bysshe Shelley. "The Cloud" was written during late 1819 or early 1820, and submitted for publication on 12 July 1820. The work was published in the 1820 collection "Prometheus Unbound, A Lyrical Drama, in Four Acts, With Other Poems" by Charles and James Ollier in London in August 1820. The work was proof-read by John Gisborne. There were multiple drafts of the poem. The poem consists of six stanzas in anapestic or antidactylus meter, a foot with two unaccented syllables followed by an accented syllable.
Document 13: 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 14: London sewerage system: Joseph Bazalgette, a civil engineer and Chief Engineer of the Metropolitan Board of Works, was given responsibility for the work. He designed an extensive underground sewerage system that diverted waste to the Thames Estuary, downstream of the main centre of population. Six main interceptor sewers, totalling almost 160 km (100 miles) in length, were constructed, some incorporating stretches of London's ``lost ''rivers. Three of these sewers were north of the river, the southernmost, low - level one being incorporated in the Thames Embankment. The Embankment also allowed new roads, new public gardens, and the Circle line of the London Underground. Victoria Embankment was finally officially opened on 13 July 1870.
Document 15: Johannes Hudde: As a "burgemeester" of Amsterdam he ordered that the city canals should be flushed at high tide and that the polluted water of the town "secreten" should be diverted to pits outside the town instead of into the canals. He also promoted hygiene in and around the town's water supply. "Hudde's stones" were marker stones that were used to mark the summer high water level at several points in the city. They later were the foundation for the "NAP", the now Europe-wide system for measuring water levels.
ground_truth: officially opened on 13 July 1870
sub_queries: Who is Claire Clairmont's sister? Answer: Mary Shelley
What city is Mary Shelley from? Answer: London
when was the sewage system built in London Answer: officially opened on 13 July 1870