[4] The large delta the creek once supported was an important stop for migratory waterfowl and other wildlife.

Most of the lower parts of the creek are devoid of native vegetation due to the flood control project, reducing the habitat of the endangered California clapper rail and other species that use the creek.

The headwaters of the creek are lined with non-native trees like eucalyptus, cypress, and Himalayan blackberry, displacing the native riparian plants like dogwood and willow.

The creek sometimes runs dry due to the non-native vegetation lowering the water table at the source.

The California clapper rail is expected to reinhabit the new salt and freshwater wetland, along with other species displaced by the flood control works.