The position of the town on the edge of the Somerset Levels, where they meet the Bristol Channel, has resulted in a history dominated by land reclamation and sea defences since Roman times. Burnham was seriously affected by the Bristol Channel floods of 1607, and various flood defences have been installed since then. In 1911, a concrete sea wall was built, and after the Second World War further additions to the defences were made, using the remains of a Mulberry harbour. The present curved concrete wall was completed in 1988. There have been many shipwrecks on the Gore Sands, which lie just offshore and can be exposed at low tides. The Bridgwater Corporation sent the first lifeboat to Burnham in 1836; the present rescue service is provided by the Burnham-on-Sea Area Rescue Boat. The need to protect shipping using the channel has also led to the development of the lighthouses, which are prominent landmarks. The original lighthouse, known as the Round Tower, was built to replace the light on the top of the 14th-century tower of St Andrews Church. The four-storey round tower was taken over and improved by Trinity House in 1815, and was operational until 1832. The top two storeys were later removed, to prevent confusion with the new lighthouse. The 110 feet (34 m) pillar or High Lighthouse and the low wooden pile lighthouse or Lighthouse on legs on the beach were built to replace it.