one-vote in the 1960s. It passed the Land Use and Development Law (Act 250) in 1970, to discourage suburban sprawl and to limit major growth to already developed areas. The law, the first of its kind in the nation, created nine District Environmental Commissions appointed by the Governor, who judged land development and subdivision plans that would have a significant impact on the state's environment and many small communities. As a result of Act 250, Vermont was the last state to get a Wal-Mart (there are now six Wal-Marts in the state, as of November 2017, but only three — in Williston, St. Albans, and Derby — were newly built from the ground up). Because of the successful attempts to dilute what is perceived as the original intent of Act 250, and other development pressures, Vermont has been designated one of America's most "endangered historic places" by the National Trust for Historic Preservation. From 1856 (the first presidential election after the Republican Party's founding) to 1988, Vermont voted Republican in every presidential election except 1964, when Democrat Lyndon B. Johnson became the first of his party to carry the state amidst a national landslide. Since 1992, Vermont has voted Democratic in every presidential election, marking a massive shift in the state's politics. In 1995, the state banned the spreading of manure from December 15 to April 1, to prevent run-off and protect the water. Therefore, farms must have environmentally approved facilities to store manure during this time frame. While the state voted largely Democratic, Republican Governor Douglas won all counties but Windham in the 2006 election. A controversy dating from 1999 has been over the adoption of civil unions, an institution which grants same-sex couples nearly all the rights and privileges of marriage at the state, but not federal, level. In Baker v. Vermont (1999), the Vermont Supreme Court ruled that, under the Constitution of Vermont, the state must either allow same-sex marriage or provide a "separate, but equal" status for them. The state legislature chose the second option, by creating the institution of civil union; the bill was passed by the legislature and signed into law by Governor Howard Dean. In April 2009, the state legislature overrode governor Jim Douglas's veto to allow same-sex marriage, becoming the first state in the nation to legalize same-sex marriage through legislation. In September 2009, Vermont became the fourth state in which same-sex