dijken

Dijken, or dikes in English, are long, elevated barriers designed to keep water out of land that lies below or near sea level. In Dutch, dijk means a dike or levee; dijken is the plural. They safeguard towns, farmland, and infrastructure by managing water levels in coastal zones, rivers, and polders.

Historically, dikes were built of earth and clay, sometimes reinforced with stone or reed. In the Netherlands and neighboring regions, a dense network of river and coastal dikes developed from medieval times onward to reclaim land from water and to protect population centers from flood events. After major floods in the 20th century, large-scale works such as the Delta Works and its components, including the Oosterscheldekering, were constructed to provide robust protection against storm surges.

Construction and maintenance regard dikes as integrated systems. Typical dikes consist of an outer slope, a crest, and an inner core, with drainage and pumping arrangements to control water levels. In the Netherlands, maintenance is organized by water boards (waterschappen) and coordinated with national safety standards; regular inspections, strengthening, and sometimes raising dikes are common to ensure ongoing protection. Many regions rely on dike rings, where several dikes encircle a low-lying area to provide regional flood defense.

Types of dikes include sea dikes, which protect against coastal flooding; river dikes, which defend settlements along waterways; and reinforced coastal dunes that function as natural and engineered barriers. Notable examples in the Netherlands include the Oosterscheldekering storm surge barrier and the Maeslantkering movable barrier, both part of broader flood-defense programs. Globally, dikes appear in various forms to protect populations and agricultural land from river and coastal flooding, particularly in low-lying or delta regions.

The ongoing challenge of climate change, sea-level rise, and subsidence has heightened emphasis on dike maintenance, upgrading, and integration with land-use planning and broader water-management strategies.