Monumental Questions - Tell me More About Cache Creek

Kristie Ehrhardt • May 11, 2022

Cache Creek flows past Valley Vista Regional Park as it enters Capay Valley

Cache Creek begins at Clear Lake and is the only outlet for the Lake. The Cache Creek watershed flows east through Lake, Colusa and Yolo Counties and eventually into a settling basin near Woodland where the sediments are allowed to settle out and the water is then released into the Yolo Bypass and eventually into the Sacramento River through a series of flood control channels.


Upper Cache Creek courses through a canyon vegetated mainly with chaparral and is generally inaccessible. There are a few tributaries that flow into Cache Creek but the two major tributaries are the North Fork and Bear Creek. The North Fork begins north of Clear Lake on the slopes of Goat Mountain in the Mendocino National Forest, through the Indian Valley Reservoir and into Cache Creek below Highway 20. Bear Creek flows through the wildflower hotspot of Bear Valley and joins Cache Creek in Colusa County, then progresses through Yolo County’s splendid Capay Valley.


The name “Cache Creek” comes from the then Canadian-owned Hudson Bay Company, which began exploring Northern California via the Siskiyou Trail between 1820 and 1830. In 1828 they began trapping along the Sacramento River and caching their furs and pelts along the river’s tributaries, including Cache Creek – and the name stuck.


A landslide that resulted from the 1906 San Francisco earthquake temporarily blocked Cache Creek north of the town of Rumsey. The blockage caused the creek level to drop drastically and, in some places, it went completely dry. Eventually the creek broke through the mud and caused severe flooding in Rumsey. A rock ledge, called the Grigsby Riffle, approximately a mile and a half downstream from Clear Lake restricts water flow and increases the chances of flooding for communities around the lake. In 1914, a dam was constructed on the main fork of Cache Creek a few miles downstream of Clear Lake. The dam, cleverly named Cache Creek Dam, was built to increase the lake’s capacity and to regulate the outflow but the narrow, shallow creek channel does not allow the water to flow as fast as the dam can release it. This causes the water in Clear Lake to rise rapidly after prolonged rain events and to decrease very slowly. If flows were increased by altering the creek channel, communities downstream in Yolo County would be subject to flooding. This has been a long-standing squabble between counties resulting in court decisions and ongoing negotiations. The Capay Diversion Dam was constructed approximately 50 miles downstream from the Cache Creek Dam to distribute water throughout Yolo County using a network of canals and water control structures. 


Beginning in the early 1800’s and for about the next 150 years, mercury (also called quicksilver) mining took place along Cache Creek and other waterways in California. Because there were no environmental regulations then, waste from mining activities made its way uncontrolled into Cache causing an increase in mercury in both the creek and eventually the Sacramento River. In 2004 the Environmental Protection Agency (EPA) stated that the mercury level was continuing to rise in Cache Creek and that the source was nearly forty old mines along the drainage. Several partners including the Bureau of Land Management (BLM), the Cache Creek Technical Advisory Committee, UC Davis, Tuleyome and others are working to monitor mercury levels and to organize and guide mine-remediation.


Although barriers exclude fall run chinook salmon and steelhead from migrating up Cache Creek, in years with very high flow conditions, some salmon may spawn in the lower regions of the creek. The portion of the creek above the Capay Dam provides one of the best native fisheries for pikeminnow, hitch California roach and Sacramento suckers on the west side of the Valley. Other species include large and smallmouth bass and catfish.


Tuleyome led the effort to have thirty-one miles of Cache Creek designated as a California Wild and Scenic River and the watershed includes the 27,245-acre Cache Creek Wilderness Area which is managed by the BLM. It is home to two herds of Tule Elk, Bald Eagles and many other species of plants and wildlife. Further downstream, the Cache Creek Conservancy has restored a 130-acre site known as the Cache Creek Nature Preserve. Cache Creek offers many recreational opportunities including whitewater rafting (spring and summer when water is released), kayaking, canoeing, tubing, hiking and camping and more.


-Kristie Ehrhardt; kehrhardt@tuleyome.org


Tuleyome Land Conservation Program Manager

RECENT ARTICLES

By Ellen Jenkins July 2, 2026
From left to right, Horticulture Interns Ellen Jenkins, Rithika Warrier, and Diego Barraza Hernandez, with Education Associate Geoff Benn, who coordinates the internship program. From September to June, I worked as a Horticultural Intern at Tuleyome. Each week at the Woodland Regional Park Preserve, I would meet with my mentor Teri Barry. Over the course of the year, we worked together identifying, documenting, and analyzing the preserve's growth. Through this opportunity, I gained experience in hands-on restoration efforts, familiarity with plant taxonomy and classification, and community outreach.
By Kristie Ehrhardt July 2, 2026
I’m sure you already know that the Bald Eagle is used as a symbol of our Nation’s freedom, strength, perseverance and independence. It is said that our founding fathers chose the Bald Eagle to adorn our Great Seal because it is indigenous to North America and if you look closely at it, you’ll see that it is holding 13 arrows and an olive branch simultaneously symbolizing the power of war and the power of peace. But, what about our national mammal? Er, maybe you didn’t even realize that we had a national mammal… President Barack Obama designated the American Bison as our national mammal in May of 2016. It too is endemic to North America and in prehistoric times, millions of them roamed through roughly two-thirds of the United States. Their range was known as the “great bison belt” - a stretch of habitat that encompassed the forests of Alaska, the grasslands of the North American plains and stretched from the Great Basin east to the eastern Appalachian Mountains. Side note - I’m just gonna come clean right now and tell you that the historic range of the American bison, American Buffalo or just plain bison or buffalo does NOT include the Berryessa Snow Mountain National Monument (Monument). I’m supposed to be writing about the Monument region and I picked a topic that is clearly not there but it’s important and they are impressive so please don’t tattle. Another side note - the American Bison and the American Buffalo are one in the same and both names can be used interchangeably. Its scientific name (genus and species) is actually Bison bison so I guess calling them bison is probably more scientifically accurate but either works. Bison are North America’s largest land animal; an adult male averages about 2,000 pounds - that’s a ton (thanks Schoolhouse Rock, I will never forget this one!), are about 12 feet long from nose to rump and about six feet tall. Females max out at around 1,000 pounds and are a little over nine feet long. In the wild bison can live ten to twenty years. Both females and males have massive forequarters and sport what looks like a shaggy, long-sleeved sweater. Both sexes have short, curved horns that are an integral part of their status in the herd and defensive strategy. During the snowy winters, bison display a dark brown winter coat and in the summer they show off their lighter brown summer-bods. Calves typically arrive from March through May depending on weather conditions. When they’re first born calves are an orangey-red color which earned them the nickname “red dogs”. Within a few months they become darker brown like their parents and their little horns start to poke through. Around this time they also begin to develop their iconic shoulder hump. The hump is made of solid muscle buttressed by elongated vertebrae. This dense network of muscles act as a powerhouse that allows the animal to swing its massive head from side to side and plow through icy snow to access buried forage enabling them to survive even the harshest winters. Although they are not known for keen eyesight, bison have superb senses of hearing and smell. As monumental (get it?) as these animals are, they are shockingly quick and agile. Bison have been clocked at running 35 miles per hour (!), they can spin and turn on a dime, leap over high fences and are incredibly adept swimmers. All these mad skills on a strictly vegetarian diet - that’s ruminant efficiency. For thousands of years, before the European settlers arrived, Native Americans of all tribes and regions revered the bison. They were the cultural, spiritual and resource backbone of indigenous societies across the United States. Every part of the animal was used; the meat was consumed, the hide was used for clothing, shoes and shelters, and the bones and hooves were used for tools and weapons. Even the sinew was used for sewing and bow strings. Everything was copacetic then came the Europeans with their domestic cattle diseases and thoughtless greed. Bison were hunted to near extinction within roughly just 100 years. Their numbers went from an estimated 60 million (!) to less than 550 individual animals by 1889. They were hunted mercilessly and their habitat destroyed, some say as a way to control the Native Americans by removing their primary resource. One of the buffalo’s biggest fans was President Teddy Roosevelt. In the early 1880’s he traveled to what is now North Dakota (shout out to my people!) to hunt. After recognizing the bison’s diminishing population numbers he co-founded the American Bison Society in 1905 to help conserve and protect this American emblem. For many years the few buffalo that remained were only found in national parks and preserves but primarily on Native American reservations. Had it not been for the willingness of tribes across the country to work with interested individuals and state and federal governments, the American Bison would be gone today. Much like the Bald Eagle, the bison is an authentic symbol of American character and as it turns out, another one of the greatest conservation success stories in U.S. history. The bison within the Yellowstone National Park boundaries are direct descendants of the original animals that roamed our country’s grasslands and are the only herd that still occupy their original prehistoric location. This free-ranging herd numbers approximately 5,500 animals and is the largest herd on public land. Recovery efforts paid off and today bison can be found in all 50 states including private and tribal lands, national parks and wildlife refuges.