The creek has a tributary stream named Twelvemile Creek, which joins it from the southwest along Westborough Blvd. in South San Francisco.[4]
History
The large delta the creek once supported was an important stop for migratory waterfowl and other wildlife. However, like many urban creeks, Colma Creek has been surrounded by
flood control walls, buried in some parts, and had much of its large delta filled in by developers. 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. In 2005, Shelterbelt Builders developed a habitat restoration plan to return the creek to its former state by removing invasive and non-native plants and replanting native,
riparian plants at the source.[3] In addition, in South San Francisco, new wetland was created to mitigate wetland lost to floodwall construction and improvements. The California clapper rail is expected to reinhabit the new salt and freshwater wetland, along with other species displaced by the flood control works.[5]
Watercourse gallery
On the west side of El Camino Real in front of Woodlawn Memorial Park, Colma, looking northwest
By the South San Francisco BART station, looking northwest along the border with Colma
At Chestnut Ave, looking southeast, just above where Twelve Mile Creek joins from the right
Twelve Mile Creek at Antoinette Lane, South San Francisco, looking southwest, upstream
At Orange Memorial Park, South San Francisco, looking northwest into the park
At S. Linden Ave, South San Francisco, as the creek approaches the railroad tracks and US 101 on its way to the bay