Coastal development can cause increasing levels of pollution in the oceans, which often come from sewage and industrial wastes, as well as from the so-called "urban runoff," which is the result of rain washing out of urban areas. In addition to breaking the chemical balance of the ocean waters, coastal pollution also include the increasing generation of solid waste. The high number of cars and factories is the main cause of air pollution, another environmental problem found in over-developed coastal areas.
Coastal development negatively affects many species living in the coast. Tourism, which often takes place in coastal areas, also contributes towards biodiversity loss. Mass tourism is the main threat to marine turtles, such as the loggerhead, which is endangered. On the Mediterranean coast, numerous nesting beaches are also top tourist destinations. In addition to nest destruction, the lights of coastal bars and hotels confuses young animals during their journey to the sea. Coastal development also damages coral reefs, one of the most fragile ecosystems in the world.
Closely linked to uncontrolled human development, coastal erosion is a global problem that affects coastal ecosystems. Salt marshes, mangroves and other wetland ecosystems are especially vulnerable to the increasing human presence on the coasts. In addition to causing the depletion of soil nutrients, coastal erosion also contributes to the eutrophication (the introduction of excess nutrients to water) of oceans or mineral saturation, which is damaging to sea life.
One of the first environmental impacts of coastal development is often deforestation. In South America, less than 10 percent of the Brazilian Atlantic Forest remains, according to Conservation International. Although sugar cane and coffee plantations contributed in the past to this decline, the increased expansion of urban areas is the main cause of forest loss today. In North America, coastal native forests have been decreasing in size, since the arrival of the first European settlers.