Due to climate change and relative sea-level rise, the dikes will eventually have to be made higher and wider. This is a long term uphill battle against the sea. The needed level of flood protection and the resulting costs are a recurring subject of debate, and involve a complicated decision-making process. In 1995 it was agreed in the Delta Plan Large Rivers and Room for the River projects that about 500 kilometres of insufficient dyke revetments were reinforced and replaced along the Oosterschelde and Westerschelde between 1995 and 2015. After 2015, under the High Water Protection Program, additional upgrades are made.