Congress doesn't get high marks from the public very often these days. An action that surely does merit praise is the quick and overwhelming approval last month of the Great Lakes-St. Lawrence River Basin Water Resources Compact. In August, the U.S. Senate ratified the compact without objection before its recess, and the House Judiciary Committee also approved the legislation. Hope that the full House would do likewise was not misplaced. It approved the compact by a vote of 390-25. President Bush promptly signed the legislation into law. This compact is tremendously important to the people of the eight Great Lakes states. Its purpose -- to prevent diversion of water from the Great Lakes Basin to other regions or countries -- will go a long way toward protecting the ecosystem. The concern, that Great Lakes water might become a commodity that state law alone could not protect, was very real and required preemptive action by Congress. Because the compact includes, in addition to eight states, two Canadian provinces, it is an international treaty as well as a federal law. It has been nearly a decade since the compact project began. A milestone was passed in 2005 when the governors of all eight states signed it. The next stage was obtaining the ratification of all eight state legislatures, each with its own take on the Great Lakes. That was achieved just this spring. Most had thought getting the compact through Congress would be yet another mountain to climb. But the legislation sailed through both houses. Perhaps lawmakers understand what we know to be true: The immense but extremely fragile Great Lakes ecosystem, in addition to being home to some 25 million people, defines this region. And it is a national treasure as well. This legislation was a major step toward assuring the protection of the Great Lakes watershed far into the future.