Thomas Howe Scanlan, Reconstruction mayor of Houston, son of Timothy Scanlan, was born on November 10, 1832, in Castle Mahon, Limerick County, Ireland. When he was seven his father took the family to New York. In 1853 Thomas moved to Houston and entered the mercantile trade. During the Civil War he made a fortune smuggling cotton through Mexico. He invested his new wealth in valuable real estate in Houston and Galveston. On April 28, 1861, he married Harmena Ebert, a member of a prominent Houston family. They were members of Sacred Heart Catholic Church. Of their ten children, seven daughters survived. After Union troops occupied Houston in June 1865, Scanlan declared himself a Republican. Radical Reconstruction began in 1867 when Gen. Joseph J. Reynolds, commander of the Department of Texas, replaced traditional Democratic leadership in city government with loyal Republicans. In August 1868 Scanlan accepted the appointment as alderman of the Third Ward. In this position he guarded against corruption by insisting on strict compliance with terms by city contractors. Beginning in August 1868 he served as chairman of the finance committee. He greatly improved the city's financial condition. This experience enabled him to manage the city as mayor, a position to which he was appointed in 1870. During his mayoralty for the first time four out of the ten appointed aldermen were black. Scanlan promoted the cause of freedmen by appointing blacks to the police force and supporting the election of black councilmen in 1872. His administration continued the other policies initiated by the Democratic party after 1865. Long-term bonds for municipal improvements were paid for by an ad valorem tax rate of 2 percent. Scanlan's city improvements included paved streets, sidewalks, a new market house, better roads and bridges, improved navigation of Buffalo Bayou through dredging of the canal, and a sewer system, all of which had long been goals of the city. Though the people wanted these improvements, they disliked the tax burden to pay for them. The Democrats seized the opportunity to accuse Scanlan of graft and wasting city revenues. In large part these accusations stemmed from the cost of constructing the market house. After Scanlan's election to a second term, construction began in 1872 at a proposed cost of $228,000. The structure's plans were altered to make it a civic monument. The city hall and market house, completed during Scanlan's third term in June 1873, included a 1,000-seat theater, retail shops, and professional offices. Houstonians now had an elaborately appointed building costing over $400,000. On July 8, 1876, however, the market house was destroyed by fire, and when rebuilding cost less than $100,000, charges of waste and corruption abounded. Although the accusers overlooked the fact that the new building was constructed on the old foundation, omitted the Italianate elegance, and lacked the theater, Scanlan and the Republicans had lost control of the city to the Democrats once again.
In 1875 President Ulysses S. Grant named Scanlan postmaster of Houston. He served until 1879. His interest in municipal improvements continued as he actively invested time and money in the Houston City Street Railway Company, the Texas Western Railroad, the Houston Gas Light Company, and the Houston Water Works Company. Thomas W. House was president and Scanlan vice president of the gas company. Scanlan became the first president of the Houston Water Company in 1881, with House as vice president. But the company proved unable to keep up with city expansion, and major fires in 1886, 1891, 1894, and 1901 had to burn themselves out because there was no water pressure at the hydrants. Scanlan's explanation in each case was that the 1878 franchise called for pipes that were so small that pressure levels could not be maintained. Another source of grievance against the company was the inability to provide the city with clean water. In defense against both charges, the company reported that 52 percent of money invested in the company was being spent on new mains, on drilling for artesian wells, and on doubling the plant's pumping capacity. But the company persistently refused to install water meters and to stop the sources of pollution above its reservoir. It also continued to use water from the contaminated Buffalo Bayou. The chronic failure of the company to provide fire protection and pure water caused a clamor for municipal ownership. The city council offered to buy the waterworks in 1903. Settlement was finally concluded in 1906 after an arbitration board set the price. After the sale of the waterworks in June 1906, Scanlan vacationed at his summer home in Chicago, where he died suddenly on July 9, 1906. His wife had died in Houston on March 20, 1898. Both are buried in Glenwood Cemetery, Houston. Scanlan's daughters received a multimillion-dollar estate in real estate and oil property. His estate executor, Kate Scanlan, built the Scanlan Building in 1909 and named it in his honor.