IRWD’s San Joaquin Marsh is a 300-acre water filter disguised as a nature preserve, purifying urban runoff in the most beautiful way while providing a sanctuary for photographers, birdwatchers and nature-enthusiasts alike.
Customers recently enjoyed a guided photo walk around one of the Marsh’s ponds, where they were treated to the sights and sounds of local and migratory birds while watching a gorgeous summer sunset.
With 12 miles of walking trails, the Marsh is a beautiful place to enjoy nature. But its importance goes beyond aesthetics.
Why is the Marsh so important?
These wetlands are a critical component of IRWD’s Natural Treatment System, also known as NTS. The first and largest of IRWD’s NTS sites, the Marsh was established in 1997. It naturally cleans urban runoff (i.e., pollutants from washing your car or hosing off your driveway) from the San Diego Creek before water makes its way to our oceans. Nearly 95% of the dry-weather runoff in San Diego Creek is diverted into the Marsh, where about 75% of the nitrogen in urban runoff is removed simply by giving the water time to interact with plants and soils in ponds and wetlands. This helps to protect the environmentally sensitive Upper Newport Bay and improves the water quality of Orange County beaches overall.
Learn more about the Marsh at IRWD.com/marsh.
IRWD’s Natural Treatment System
IRWD’s NTS uses smaller, man-made wetlands modeled after the natural treatment ponds found at the Marsh. Today, there are 46 NTS sites throughout Orange County in addition to the Marsh. The Marsh cleans 1.7 billion gallons of dry-weather runoff each year, while the additional 46 sites clean a total of 241.5 million gallons annually.
“The extensive, collaborative work of IRWD staff at NTS sites over recent years has contributed significantly to improvements in local water quality,” Natural Resources Manager Ian Swift said. “It’s just one of many examples of IRWD’s longstanding commitment to sustainability.”
Learn more about the Natural Treatment System and IRWD’s commitment to sustainability and urban runoff treatment at IRWD.com/nts.
Visit the Marsh
The Marsh is open daily from dawn to dusk for self-guided access, with more than 12 miles of trails to explore. For directions, a trail map and Marsh rules, visit IRWD.com/marsh.
