The areas to the south of Santa María are considerably affected by volcanic activity at Santiaguito. Currently, the most common volcanic hazards at Santa María are lahars, which frequently occur in the rainy season due to heavy rainfall on loose volcanic deposits. Lahars are particularly large and frequent during periods of high volcanism at Santiaguito. The town of El Palmar, from Santiaguito, has been destroyed twice by lahars from Santiaguito forcing the town to be moved to the present Nuevo El Palmar, and infrastructure such as roads and bridges have been repeatedly damaged. Lahar deposits from Santiaguito have affected rivers all the way downstream to the Pacific Ocean.