Water Quality


Channel Islands National Marine Sanctuary provides habitat for a wealth of biological diversity, outstanding recreational opportunities and spectacular scenery. Every organism that resides within or moves through the sanctuary depends upon clean water, as do all our commercial and recreational uses.

Poor water quality can cause illness or disease, impair condition and reproductive capacity, and decrease productivity in marine organisms. It can also endanger human users of the sanctuary. Sources of water quality impairment in the sanctuary are land-based discharges from the mainland and the islands (e.g., runoff can include sediment, bacteria, and agricultural-based chemicals such as pesticides and herbicides), vessel discharges from recreational, commercial, and industrial vessels (e.g., sewage, bacteria, and marine debris), and discharges associated with oil production (Engle 2006). Nonpoint source pollution from the mainland may reach the eastern portion of the sanctuary (Anacapa and Santa Cruz Islands) during major runoff events via plumes from the Ventura and Santa Clara Rivers (Engle 2006). Agricultural and urban runoff, as well as effluent from municipal wastewater treatment plants, may be some of the sources of pollution from the mainland that reach the sanctuary. Because pollutants can be carried to the sanctuary by ocean currents, or transported through the food chain, the spatial extent of water quality threats is much larger than the sanctuary itself. For example, the pesticide DDT was manufactured in Los Angeles until the early 1970s and discharged into the ocean off the Palos Verdes peninsula. The chemical-contaminated fish within those waters were in turn eaten by seabirds and marine mammals. This affected foraging communities throughout southern California, including the Channel Islands, long after the chemical production stopped. Levels of DDT and a derivative DDE are still measurable in sediments. Some wildlife species such as Bald Eagles are only now beginning to recover.

There are a number of watersheds located on the northern Channel Islands, contributing a small amount of fresh water into the sanctuary. Most fresh water entering the sanctuary region, however, comes from the streams and rivers along the mainland coast, such as the Santa Clara and Ventura Rivers, which provide the majority of the freshwater and sediments into the Santa Barbara Channel. The Santa Ynez and Santa Maria Rivers provide major drainages north of Point Conception. These major rivers have been shown to transport sediment plumes that reach sanctuary waters. The regional coastal mainland also includes the San Antonio Creek watershed and 41 small coastal watersheds on the south side of the Santa Ynez Mountain Range. The creeks of these watersheds provide important nutrients to the marine environment (as well as pollution from agricultural and urban runoff).

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Map Repository

Cruise Ship Anchoring Sites

Cruise Ship Anchoring Sites

This map depicts permitted areas to anchor large cruise ships within Monterey Bay.
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Project Database


Plumes and Blooms

The Plumes and Blooms Project is aimed at understanding the ocean color roles of sediment plumes and phytoplankton blooms in a complex coastal ocean using satellite and ship acquired data.


Santa Barbara Sediment Trap Time-Series Program

Since August 1993, a moored sediment trap has been located near the center of the Santa Barbara Basin (SBB) (34˚14' N, 120˚02'W). Over the course of the time series, the deep trap was deployed between 500 m and 540 m in a total water depth of approximately 590 m. A second shallow trap was added in 2009 and is located at ~ 250 m depth. Sinking particles have been continuously collected by an automated Mark VI sediment trap (0.5 m2 trap opening) equipped with 13 sampling cups poisoned with sodium azide on a rotating carousel. Each trap sample represents approximately two-weeks of collection time. Occasional disruptions in the time series data set are typically due to trap clogging associated with periods of high mass flux or due to loss of the sediment trap.


Southern California Bight Regional Marine Monitoring Program (Bight Program)

The Southern California Bight (SCB) is a unique ecological and economic resource, home to some of the most productive coastal ecosystems, but also some of largest pollutant inputs in the United States. Historically, environmental monitoring of the coastal environment has been temporally intensive, but spatially focused on narrow areas closest to regulated discharges, providing a potentially biased perspective of overall coastal sediment quality. Beginning in 1994 and conducted approximately every five years thereafter, nearly 100 regulated, regulatory, non-governmental or academic organizations join forces to implement the SCB Regional Marine Monitoring Program (the Bight Program).