Redwood Creek
A tributary joins Redwood Creek in Reinhardt Redwood Regional Park near Canyon, California
Location
Country	United States
State	California
County	Contra Costa
Physical characteristics
Source	Redwood Regional Park
Mouth
• coordinates	37.79166°N 122.13097°W
Length	3 mi

Redwood Creek is an approximately 4 mile-long perennial creek in Contra Costa County, California, in the San Francisco Bay Area. It is named for the redwood forest where it originates.

Course

Redwood creek begins as two spring-fed branches in Dr. Aurelia Reinhardt Redwood Regional Park near Canyon and Moraga, California. It flows generally south through its narrow and densely-wooded canyon for the entirety of its course. It receives numerous intermittent tributaries originating out of the canyon. Historically, Redwood Creek was a tributary to San Leandro Creek, but following the construction of the Upper San Leandro Reservoir in 1926, the creek became a tributary to the lake.

Geography

Redwood Creek is located in Contra Costa County, California, in the San Francisco Bay Area. Though the redwood creek watershed itself has very little development, it is surrounded by a rapidly-encroaching network of suburbs.

It is located in the westernmost of a series of linear north-south canyons in the Berkeley Hills. Located directly across the San Francisco Bay from the Golden Gate, the low hills where Redwood Creek originates are subject to frequent low fog which provides conditions suitable for Coast Redwood (Sequoia sempervirens) in an environment with otherwise too little precipitation to support them. On average the watershed receives 27.5" of rainfall in a year.^[1]

Redwood Creek is paralleled by the Stream Trail in Reinhardt Redwood Regional Park for much of its length and can be accessed from a number of trailheads on Skyline Road.^[2]

Ecology

Redwood Creek is incredibly unique among streams of the East Bay in that it is primarily forested with Coast Redwood. While common in areas closer to the coast, redwoods are absent from the rest of the East Bay and the inland South Bay due to the area's generally hot climate and lower precipitation than areas closer to the coast. A low break in the Berkeley Hills allows for frequent infiltration of maritime fog into the canyon of Redwood Creek. This fog, in addition to high average precipitation, supports the redwoods which are able to absorb water through their leaves.^[3]

Vegetation typical of the redwood forest habitat grows along Redwood Creek, including California Bay (Umbellularia Californica), California Hazel (Corylus cornuta var. Californica, Pacific Madrone (Arbutus menziesii), Western Sword Fern (Polystichum munitum), California Blackberry (Rubus ursinus) and Redwood Sorrel (Oxalis oregana) are commonly found.

Exotic and invasive species of plants, which compete with native species are also prevelant in the Redwood Creek catchment, especially Himalayan Blackberry (Rubus armeniacus) which covers large swaths and grows rapidly.

Black-tailed deer, Coyotes, Raccoons and a wide variety of other mammals utilize Redwood Creek and the habitats found in its watershed year-round. Redwood Creek provides ample shade and cool, consistent flow through the summer, a rarity in the hills of Contra Costa County.

References