Forgotten waterways shape the land. Today we’re exploring Islais Creek Channel. Once known as Du Vrees Creek, Islais Channel and Islais Swamp, this small creek has a rich history. Its name comes from the Salinan Native American word “slay” or “islay”. This refers to the Prunus ilicifolia wild cherries that grew here.
Let’s travel back to the Gold Rush era. This area transformed into an industrial hub. Sadly, the creek’s condition declined. Imagine the chaos. Then the devastating 1906 San Francisco earthquake struck. The city decided to reclaim the creek using earthquake debris. This reduced the waterbody to its present size. Much of Islais Creek became an underground culvert. Remnants still exist today at Glen Canyon Park and Third Street.
Interestingly, the historic Islais Creek was the largest body of water in the city. It covered nearly 5,000 acres. That is over 7.8 square miles. The creek had two main branches. One originated near the southern slope of Twin Peaks. The other began at the intersection of Cayuga Avenue and Regent Street. Precita Creek also joined Islais Creek.
From its sources in Glen Canyon, the creek stretched about 3.5 miles to the San Francisco Bay. The mouth was nearly 2 miles wide. It provided up to 85% of San Francisco’s drinking water. Urban development reduced the watershed by roughly 80%. Many neighborhoods were once covered by the creek. Bernal Heights, Hunters Point, and Visitacion Valley are examples.
Fast forward to 2007. The San Francisco Public Utilities Commission investigated “daylighting” underground portions of the creek. As of 2009, remnants remained in Glen Canyon Park and near Third Street.
The name Los Islais first appeared on Mexican maps in 1834. By 1850, farmers used the creek’s water to irrigate crops. The Gold Rush brought decline. A railroad trestle was built over the creek in the 1860s. In 1883, Islais Creek was declared a non-navigable waterway.
In 1871, the area became known as the city’s “New Butchertown”. Over 100 slaughterhouses opened. The creek deteriorated further. It became a dumping place for garbage, sewage, and animal waste. San Franciscans even called it “Shit Creek”.
After the 1906 earthquake, the creek was filled with debris. During World War II, it served as docking areas for tugs. The largest copra coconut processing plant on the West Coast was located here. An abandoned five-story copra crane still stands as a historic landmark. In the 1950s, Islais Creek was home to the largest sardine canning industry in the world. A water treatment plant improved the creek’s condition in 1970.
Community organizations formed to improve the creek. Friends of Islais Creek was established in 1984. In 1998, the Muwekma Ohlone Park was finished. It is located adjacent to Pier 80. The park has since become an important habitat for wildlife.
In 2001, construction crews cracked a sewer line while working on the Muni Metro T Third Street line. This flooded the creek and Muwekma Ohlone Park with sewage. The park had to be excavated.
Today, Islais Creek Park features a historical information sign, a trail, public art from a copra crane, and a pier. The Third Street Bridge is a major crossing. It carries the T Third Street light rail line.
Islais Creek is a culvert that carries storm water, sewage, and wastewater. This can cause a public health hazard. The creek displays higher levels of heavy metals and bacteria. Several projects were developed to improve the ecological situation of the Islais Creek Channel. A restored Islais Creek Channel can knit together neighborhoods.