Protecting Our Watershed


The City of Santa Ana sits on Southern California’s largest watershed, covering nearly 3,000 square miles of mountains, foothills and valleys.

What is a watershed? It’s an area of land that drains rainfall to a common outlet such as a reservoir or ocean. Watersheds consist of surface water like lakes, streams, reservoirs, and wetlands. These water bodies supply our drinking water, water for agriculture and manufacturing, offer opportunities for recreation and provide habitat to numerous plants and animals.

Snow from the San Bernardino Mountains melts and flows down the Santa Ana River and its many streams and creeks—called “tributaries”—feeding the Santa Ana River Watershed. The largest tributary within Orange County is Santiago Creek.


Since water flow is interconnected, what we do on the land affects the quality of our water for everyone else and can have a big impact on our natural systems, including the plants, animals, and fish that depend on them. That is why protecting our watershed is important to our community.

When it rains, storm drains carry rainwater to our creeks, streams and eventually the ocean without any filtering or cleaning. Storm drains are designed to drain excess water from solid surfaces such as paved streets, parking lots, sidewalks and roofs. Along the way to the storm drains, water picks up trash, debris, and chemicals found on the ground. If we are not careful, our daily activities can lead directly to water pollution problems. By taking personal responsibility, you can prevent water pollution and help keep our creeks, rivers, bays and ocean healthy:


  1. Don’t litter. Recycle soda cans and throw candy wrappers in the trash.
  2. Take used motor oil and old paint to a recycling center.
  3. Use a broom to sweep instead of hosing off sidewalks and driveways. This will help prevent ocean pollution and save water.
  4. Never use fertilizer and pesticides before rain. It can wash harmful chemicals into storm drains that lead directly to the ocean.
  5. Pick up after your pets and throw waste in the trash.
  6. Volunteer to help clean up your local watershed.



Last year, Santa Ana Water Resources Division collaborated with more than 10 agencies including state, county and city governments to underwrite, produce and install Santa Ana River Watershed displays in over 50 park locations throughout the basin. In the City of Santa Ana alone, five displays are installed at Centennial Park, Civic Center, Santiago Creek Nature Center and the Heritage Museum of Orange County. 

The purpose of these displays is to educate the public about the importance of our watershed and promote sustainable landscaping, water conservation and pollution prevention. This project is part of our public outreach initiative to ensure a more sustainable water future for the community of Santa Ana.