Delta Works was completed by the Europoortkering which required the construction of the Maeslantkering in the Nieuwe Waterweg between Maassluis and Hoek van Holland and the Hartelkering in the Hartel Canal near Spijkenisse. The works were declared finished after almost forty years in 1997. In reality the works were finished on 24 August 2010 with the official opening of the last strengthened and raised retaining wall near the city of Harlingen, Netherlands. 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
Sacramento–San Joaquin River Delta (BiOp) lead to pumping restrictions from the State and Federal projects from the Delta, a number of potential solutions to the Delta's problems have been proposed. These followed the CALFED process which had offered several staged solutions. A first set of alternatives would maintain the Delta in its current condition and configuration. The second would restore parts of the Delta more closely to its natural state but include the construction of an additional Peripheral Canal to maintain the water supply currently provided by the Delta. The Contra Costa County Public Works Department is working with the California Coastal Commission and