Water on the Irvine Ranch : The History
A great portion of the lower portion of the ranch, from the Upper Newport Bay all the way up to Red Hill in Tustin, was a large, marshy bog called “Cienega de Las Ranas” or “Swamp of the Frogs.” Present day shopping and business areas like Park Place, The Irvine Industrial Park, and The District in Tustin would have been a swampy mess.
All of the rain that fell on the western foothills of the Santa Ana Mountains and the eastern slopes of the San Joaquin Hills drained into this long, wide swampy stretch land. During the rainy winter months, these lowlands could not be crossed, even on horseback.
Why Swamp of the Frogs? Because of the millions of tree frogs that lived in the marsh. Their croaking chorus could be heard for miles. In fact, travelers in the early 1800’s knew they were approaching because of the song of the frogs, even in the darkness of night.
The impassability of the swamp forced the re-routing of the El Camino Real further north towards the foothills. This was troublesome for stagecoach travelers passing between Los Angeles and San Diego. The stage was forced to slow down because of the hilly terrain, so passengers were vulnerable to robbers.
Later, The Swamp of the Frogs and its vast groundwater supply was the key to the success of James H. Irvine’s citrus groves. Oranges are a thirsty crop. Irvine invested greatly in digging wells on his ranch in the early 1900’s. By the 1920’s, much of the marshland had been drained considerably, forcing Irvine to build a reservoir system that would irrigate his ranch on the future.
The Swamp of The Frogs Today
The original Swamp of the Frogs is a memory, but the marshy, preserved wetlands of Irvine are still an important natural resource today. The San Joaquin Marsh and Wildlife Sanctuary isn’t just a lovely place to visit and enjoy the tranquility of nature. These 300 acres of coastal freshwater marsh are also part of the Irvine Ranch Water District’s Natural Treatment System that naturally cleans urban runoff from San Diego Creek and helps to protect the environmentally sensitive Upper Newport Bay.
Water flows into the marsh and is filtered through the plant life there. After interacting with the bulrush and other plants for seven to ten days, up to 70 percent of the nitrogen is removed. The cleaner water is returned to the creek to continue its journey to Upper Newport Bay and the ocean.
For centuries, the water resources of Irvine area have supported the people who have lived here. Thanks to the conservation efforts of the IRWD, these same natural systems are still working to provide a cleaner, fresher environment for residents of today.