Complex sentence: The county also received national media attention because of Lake Lanier, which forms the eastern border of the county, and the scarcity of water resources during a drought that threatened water supplies for the metro Atlanta area and, downstream, areas of Alabama and Florida.
Split into simpler sentences: The county also received national media attention because of Lake Lanier, which forms the eastern border of the county. The scarcity of water resources during a drought threatened water supplies for the metro Atlanta area and, downstream, areas of Alabama and Florida.