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We all live in a watershed.

And what we do on land affects the health of waterways and the Monterey Bay. Learn more about watersheds, what’s affecting them and what you can do to help.

What’s a Watershed?

A watershed is the geographic area of land that all drains to a common waterway. Imagine you are a raindrop and you fall from the sky and land in Henry Cowell State Park. You’re going to travel from the spot where you landed to the San Lorenzo River. That means, that you’re in the San Lorenzo River watershed. Alternatively, if you (as a raindrop) fell in downtown Watsonville, you’re going to travel to the Pajaro River before entering the Monterey Bay. That puts downtown Watsonville in the Pajaro River watershed.

Since a watershed is made up of several components that are all part of the “big watershed picture,” it is important to remember that what happens on the land can affect the water. For example, if a river or stream flows through an agricultural area, it can pick up fertilizer, manure, and pesticides from farming operations that run off the land after a rainstorm. And it the river flows through an urban area, it can pick up chlorine, copper and other urban pollutants that run off of people’s yards and driveways after a rainstorm.

Threats to Watershed Health

Historically, in Santa Cruz County, some of the first threats to watershed health came from the cattle ranches established by the Spanish settlers to the region in the late 1770s. The ranches changed the ecosystem dramatically by disrupting the composition of the local wildlife populations. Logging, especially of the Redwoods, also became popular in the 1800s. Logging was arguably the most damaging practice to our local watersheds. To transport logs, pole roads were constructed in local streams. This technique caused massive erosion in the streams which caused landslides in some areas. Today, some of the biggest sources of pollution are from urban runoff and agricultural runoff.

Urban Runoff

Urban Runoff or ‘storm drain pollution’ is one of the leading causes of water pollution in this country. Urban areas contain up to 90 percent hard surfaces such as rooftops and pavement where water collects and quickly runs off. Urban Runoff is difficult to prevent because it is nonpoint pollution. That is, instead of originating from a single-point source, such as a factory or sewage treatment plant, the sources of urban runoff are spread throughout an urban area. Such sources include yards, sidewalks, streets, construction sites and parking lots. Any deposits of oil, grease, pesticides, herbicides, soil, pet droppings, etc. in these areas are flushed by rainwater and other means down the storm drains and directly into a river or bay. The EPA estimates that 70% of water pollution comes from stormwater and sewer discharge. This increase in flow can have impacts on sediment, riparian plant life, and erosion.

Agricultural Runoff

In the Monterey Bay Area there is extensive agriculture. Overgrazing and un-sustainable agricultural practices can lead to significant sediment washing into our local creeks and streams. Agriculture also uses a lot of chemicals and pesticides that can get into water. Common substances that farms use on crops are phosphorous, nitrogen plastic, and various insecticides, herbicides, and fungicides. Badly managed manure and animal feed can lead to bacteria and pathogens getting into the water.

CWC Reports

The following is a list of all of our reports. We will continue to upload reports as they are finalized. All report files posted on this list are links of downloadable PDF files. Please let us know if you have questions about the reports, as our aim is to make the information useful for local leaders, land owners, and all parties interested in watershed improvement and water quality.

Annual Reports
San Lorenzo River Reports
Central Coast Regional Snapshot Day
Urban Watch
First Flush