Discover the untold stories and natural features of the Minnesota Valley National Wildlife Refuge. Jutting out of the Minnesota River bottom, the Carver Rapids at the Rapids Lake Unit tell a story that stretches back thousands of years. From the powerful glaciers that shaped the landscape, to the short-lived ghost town of San Francisco, this historical landmark connects us to the past. We at the U.S. Fish and Wildlife Service are proud to protect these rapids and the surrounding valley, and we invite you to discover the cultural and ecological stories they tell.

Glaciers formed Minnesota’s river valley 

The Rapids Lake Unit is located in Carver, Minnesota, about 45 minutes southwest of the Twin Cities. The Minnesota River Valley formed nearly 10,000 years ago when glaciers receded from western Minnesota and melting ice formed glacial Lake Agassiz. As the lake filled and overflowed, it created glacial River Warren - what is now recognized as the Minnesota River.

At the time of formation, glacial River Warren was two to three miles wide. As the glaciers disappeared, the source feeding the river diminished, which caused water levels to drop and leave behind its old shorelines as the surrounding bluffs and terraces we see today. It is within this riverbed that the Carver Rapids were formed, the only rapids along the entire stretch of the Minnesota River, from Granite Falls to Fort Snelling.

Steamboats stuck at the Carver Rapids

Since time immemorial, the Minnesota River Valley has been an active home to Indigenous communities, including the Sisseton and Wahpeton Dakota, who had a large village near the rapids. In 1851 the area was ceded to the United States when Sisseton Wahpeton Dakota signed the Treaty of Traverse Des Sioux and when the Mdewakanton and Wahpakoota Bands signed the 1851 Treaty of Mendota. This marked the beginning of European settlement and industrialization along the river.

At the time, steamboats were the primary method of travel, predating the railroad system. However, the Carver Rapids posed a significant challenge to the new travelers on the Minnesota River. Steamboats were often unable to pass over their shallow, turbulent waters and passengers were forced to disembark and transfer to another vessel on the opposite side of the rapids. Though generally considered a nuisance, in the early 1850s, William Foster saw the rapids as an economic opportunity.

The rise and fall of San Francisco, Minnesota

In 1854, William Foster, a survivor of the Donner Party a decade earlier, had returned to Minnesota and purchased the ceded land around Carver Rapids with the intent to establish a town. Naming it after the beloved city he had left behind, Carver County’s newly founded San Francisco remains the township’s namesake.

Looking to accommodate the disembarking steamboat passengers, Foster opened various hospitably services including a hotel, restaurant and post office. The town, however, had a major flaw: it was prone to flooding, like much of the swampy Minnesota River Valley. Infrastructure and people were difficult to keep in town, and by 1860 it was abandoned. The ghost town site and the rapids, however, still exist as an interesting historical focal point and can be visited today.

The rapids still run

Despite the abandonment of San Francisco, the ecological significance of the Carver Rapids endures. The swift waters and surrounding wetlands are home to a variety of fish species, including both native and migratory species such as bald eagles, wood ducks, river otters, prairie skinks, and white-tailed deer.

If you travel the Minnesota River today, you may not even notice the Carver Rapids. At times, it is signified by just a strong ripple in the water. The river’s water levels have risen since the time of the steamboats. As upland wetlands are drained to create croplands and spur development, water is diverted directly into the Minnesota River.

Nearly a century later, growing awareness of environmental issues sparked a renewed interest in conservation efforts to protect and restore the natural resources of the Minnesota Valley. The formation of the Minnesota Valley National Wildlife Refuge in 1976 was a significant step in safeguarding the ecological treasures of the area, including the Rapids Lake Unit, which houses a visitor center. Refuge staff lead programs aimed at habitat restoration and wildlife protection, emphasizing the importance of preserving these natural areas for future generations.

Visit Carver Rapids

We’d love to see you! The area continues to be a focal point for educational programs, engaging the public in understanding the significance of the Minnesota River and its tributaries. As stewards of this remarkable place, we at the U.S. Fish and Wildlife Service invite you to walk the trail and visit the Carver Rapids, where the woven stories of the past meet the beauty of nature today.

Learn more about the Rapids Lake Education and Visitor Center. Trail conditions may vary by season.