According to the United States Geological Survey USGS Volcano Warning Scheme for the United States, the Volcano Alert Level for Haleakala as of August 2015 was normal. A Normal status is used to designate typical volcanic activity in a non-eruptive phase. Haleakala has produced numerous eruptions in the last 30,000 years, including in the last 500 years. This volcanic activity has been along two rift zones: the southwest and east. These two rift zones together form an arc that extends from La Perouse Bay on the southwest, through the Haleakalā Crater, and to Hāna to the east. The east rift zone continues under the ocean beyond the east coast of Maui as Haleakalā Ridge, making the combined rift zones one of the longest in the Hawaiian Islands chain.