Upper Merced River Watershed Council


                              Map of the Merced River and Watershed


The Merced River flows from its headwaters in Yosemite Nation Park to the to where it joins the San Joaquin River in California’s Central Valley. A significant portion of the Merced River however is impounded by the New Exchequer Dam that forms Lake McClure. There is a somewhat confusing use of names for the various parts of the river that is described here and illustrated on the map above.

The Upper Merced River goes from the headwaters in Yosemite to where this section of the river becomes Lake McClure about 5 miles above the bridge on HWY 49 at Bagby. However, the lower part of this river segment, below Briceburg where it separates from HWY 140 to where it ends above Bagby, is refered to as the lower Merced River (lower case “l”).

The Upper Merced River and the South Fork of the Merced River are designated as Wild and Scenic Rivers according to the Wild and Scenic Rivers act. The most unspoiled section of the lower Merced River section, as with much of the river within Yosemite are classified as “Wild”, the most pristine classification under the Wild and Scenic Rivers Act.

The Lower Merced River (upper case “L”) starts below the dams at Lake McClure and Lake McSwain as well as the Merced Falls Dam and the Crocker-Huffman Diversion Dam.  Together these dams completely blocks the passage of anadromous fish up the Merced River and remove almost half the natural flow of the River, and an even more during dry years.  The Lower Merced River is not designated Wild and Scenic.

Please see our page about the Wild and Scenic Status of the Merced River, and the various threats to that status.