If you’ve done a multiday rafting trip on the Rio Grande downstream of Boquillas in the Big Bend region, you probably lugged your boat off the river on a small sandy beach at Heath Canyon Ranch. If you’ve paddled the Lower Canyons, you likely launched from the same remote spot in the desert. Last year, when the longtime owners of the ranch put it up for sale, river users worried they might lose access to the land—and with it, access to the nationally designated “Wild and Scenic River.”The Nature Conservancy in Texas quelled those fears last month, when it purchased the 671-acre property and donated it to Texas Parks and Wildlife. Then, on Tuesday, officials announced that the land will be added to the adjacent…