May 15, 1885: Responding to concerns that rampant deforestation will damage New York City's water supply, the New York State Legislature sets aside 681,000 acres of land as the Adirondack Forest Preserve (at right).
May 15, 1928: In a response to the great Mississippi River Floods of the previous year, U.S. Congress enacts the Flood Control Act, directing the Army Corps of Engineers to build massive flood control systems along the lower Mississippi River and California's Sacramento River. The levee system greatly reduces the flood risk, but forever alters the ecosystem of the Mississippi Delta, contributing to today’s dire erosion problems along the Louisiana Coast.
May 15, 1989: A "Tri-Party Agreement" between Washington state and the U.S. EPA and Energy Department launches the costliest environmental cleanup to date. The Hanford Nuclear Reservation, with nearly a half-century of environmental contamination from nuclear weapons production, undergoes a reversal. Home prices in nearby towns experience an unlikely boom for years to come as highly-skilled workers flock to live near a toxic site.