Several slow moving, tide-affected major rivers in alluvial channels terminate in San Francisco and Monterey Bays. Much of the saltwater marshes on the north and south ends of San Francisco Bay are converted to salt evaporation ponds. A few slow moving perennial streams in alluvial or weak bedrock channels flowing directly to the Pacific Ocean occur in the northern part of the area. Some fast moving perennial streams in weak bedrock channels flowing directly to the Pacific Ocean occur in the southern part of the area. Reservoirs for municipal water supply are common in the northern part of the Section.
Fires are of variable frequency, season, and intensity.
This is a seismically active area with strong shaking and ground rupture. These changes related to grazing, agriculture, forestry, and urbanization. The northern part is densely urbanized. Humans have been utilizing the Section for about 8,000 years, and have been an integral part of central coast ecology for about 2,000 years, thriving on the diversity of habitats from ocean and estuary to forest, and intensively gathering numerous resources. The Spanish established missions throughout the area in the late 1700's and early 1800's, introducing agriculture and religious and social changes.