Situated in a grassland, Modesto has few distinctive natural features. One, however, stands out -- the Tuolumne River. Without it, life in Modesto and surrounding areas would not exist in its present form. The river skirts many parts of the city, forms the focal point of the Tuolumne River Regional Park and provides drinking and irrigation water.
The river's long journey begins in the Sierra and makes its way across the San Joaquin Valley to the San Francisco Bay. This journey provides an interesting tale that portrays both the progress of civilization and of the damage it has done.
As the last ice age melted to its conclusion, rivers began to flow from the Sierra toward California's great Central Valley. Formed in Yosemite National Park's Tuolumne Meadows at the junction of Lyle and Dana creeks, the Tuolumne rushes from one amazing sight to another as it rumbles down a series of waterfalls and through the Grand Canyon of the Tuolumne into the spectacular Hetch Hetchy Valley.
Disastrous flooding in the 19th century had presented a major hazard for those living downstream along the Tuolumne River. Meanwhile, the growing population of the San Francisco area demanded more water and electricity. These demands culminated in the building of dams across the valley's rivers.
The most prominent are O'Shaughnessy Dam, at the edge of Hetch Hetchy Valley, and New Don Pedro Dam, completed near Jamestown in 1971.
Behind Don Pedro and east of Groveland, the river remains officially designated as wild and scenic. Thanks to efforts of groups like The Tuolumne River Trust -- which has successfully (so far) fought San Francisco's demands for more water -- this section of the Tuolumne has been preserved. A raft trip down this portion of the river can give the impression of what life in California's riparian habitats were like before the arrival of Europeans. It is along this section that the Clavey River joins the Tuolumne.
From the foothills to the valley floor, the river's banks have always been populated -- first by Native Americans who used the river for fish and other foods, having little negative impact on their surroundings. But as the Gold Rush boomed, it brought mining to the canyon and that had terrible consequences for the river. Many gold hunters favored placer, or hydraulic, mining -- that channeled the Tuolumne's water into high-powered hoses that blasted away dirt from the canyon sides so it could be sifted for gold. Downriver the water became coated with what miners called "slickens," or the muddy and mercury-laden runoff.
Continuing west, the river passes La Grange, Waterford, Ceres and Modesto where substantial farming replaced mining as the dominant activity. In the valley, steamboats operated on the Tuolumne to haul grain from vast dryland farms to Stockton and San Francisco. The river was to early Stanislaus County what Highway 99 is today -- a major trade route.
The river's 140-mile trip finally ends as it pours into the San Joaquin River, the watery main conduit into San Francisco Bay.
The Tuolumne River Trust is sponsoring a photo exhibit, "The Clavey: A River Running Wild," at the Great Valley Museum, 1100 Stoddard Ave., starting through Dec. 31.
McAndrews is a docent and board member of the Great Valley Museum. E-mail him at firstname.lastname@example.org.