Coastal Dunes
III. Human Impacts

Coastal beaches along much of the MBNMS are eroding at a high rate (Griggs and Johnson 1979, Plant and Griggs 1991; and see Geology section). Adjacent coastal Flandrian cliffs (5,000 to 18,000 year old) are also eroding, by as much as 6 feet per year at Fort Ord.

Erosion is due to rising sea level on a geologic scale, and several much more short-term human impacts. A sand budget deficit has been created due to interception of longshore sand movement by jetties, sand mining and damming of rivers, which has impeded sediment output to beaches (Monterey Bay Dunes Coalition 1991).

Coastal dune communities are also directly impacted by human trampling, horseback-riding, agriculture, one active and two retired sewer processing plants, a freeway, trailer park and two hotels with more planned (Monterey County Herald 1995b), and a planned desalination plant (Monterey County Herald 1995a, c). Management of this ecosystem is complicated by the numerous landholders and diversity of agencies, jurisdictions and goals (Big Sur Land Trust 1992). However, major, long-term commitments of conservation through restoration have been successful (Cowan 1975, 1995, Emery 1989, Gray and Ferreira 1988) and have set the stage for ongoing efforts at Asilomar (Willoboughy 1995), Moss Landing (ABA Consultants1992) and several other Monterey Bay locations (J. Dorrell-Canepa pers. comm.).