Rivers of the Valley

Five river parks reveal why every protected acre matters in California’s San Joaquin Valley

By Rachael Kirk-Cortez
 

To the untrained eye, the San Joaquin Valley appears to be a grid of perfectly straight lines. Large highways, brimming with cars and trucks barreling through the valley, divide the land. Precise rows of orchards and crops slide past car windows in endless repetition, interrupted only by the concrete aqueducts, often mistaken for rivers, that channel water to these crops. 

Yet for those who know where to look, this same valley offers unexpected beauty, endangered ecosystems, and worthwhile opportunities for recreation. Beloved rivers, more often photographed at their headwaters in the Sierra Nevadas, peacefully wind through this same valley. Hidden in plain sight, the five parks in California State Parks’ Rivers Sector defy human-made order, reminding us that we need wild spaces to thrive.  

Where Every Acre Matters  

Less than 1% — that’s what the 5,000 acres preserved within these five parks represent. Together, they make up less than 1% of the land inside the San Joaquin Valley. Caswell Memorial State Park, Dos Rios, George J. Hatfield State Recreation Area, Great Valley Grasslands State Park, and McConnell State Recreation Area together protect parts of the Stanislaus, Tuolumne, Merced, and San Joaquin rivers as they merge and flow into the Sacramento-San Joaquin Delta. In a place where protected land is limited, every acre of these parks holds outsized importance.   

These parks offer a rare view of the San Joaquin Valley’s natural ecosystems before human intervention. Although the surrounding farmland may look like green space, it does not provide food, shelter, native habitat, or protection from predators that wild animals need to survive. These parks are essential to the survival of threatened plants and animals, from the delta button celery to the riparian brush rabbit. Paige Haller, Rivers Sector Manager with California State Parks, shares, “It’s been personally world-altering for me to experience the life and vibrancy within the ecologically important habitat these parks protect.”  

These parks are critical to a climate-resilient future. By restoring and protecting natural floodplains, these parks allow rivers to rise and spread safely, improving conditions for nearby communities, recharging aquifers, and strengthening the region’s resilience. Ongoing work in riparian oak forests to reduce their fuel load helps prevent megafires in landscapes where fire was once managed naturally.   

Recreation adds another layer of value. These parks offer a respite from the valley’s summer heat, giving visitors a place to reach the river and connect with nature. Their distance from major cities also protects dark skies, making stargazing a signature experience during campfire programs. “We all need open space,” says Danielle Gerhart, Central Valley District Superintendent of California State Parks. “We all need a place where we can enjoy nature and experience the unexpected sense of peace these parks provide.”   

They also carry cultural importance. Located within the ancestral home of the Northern Valley Yokuts, the land now contained in these parks has sustained human life since time immemorial. 

While these parks together form a connected system, each park offers something unique, inviting visitors to discover how much nuance and detail can be found within this region.

McConnell State Recreation Area: Where the Valley’s Park Legacy Began 

McConnell State Recreation Area opened in 1950 as the first state park within the San Joaquin Valley; it was created specifically to bring protected land to a region with few parks. Set along the Merced River, it has served as a welcoming gateway to the beauty of these rivers for the past 75 years. Within a small footprint of 74 acres, visitors enjoy camping, picnicking, and fishing year-round, and swimming and rafting or kayaking in warmer months.    

George J. Hatfield State Recreation Area: A Gift to California 

This park was established in 1953 on 46 acres donated by California Lieutenant Governor and State Senator George J. Hatfield and offers opportunities to kayak, canoe, picnic, swim, and fish along the San Joaquin River. Campers can look forward to campground enhancements, including new picnic tables, shade ramadas, fire rings, modernized restrooms, upgraded parking areas, and refreshed interpretive panels — updates that help the park continue its role as a place of connection and recreation.  

Caswell Memorial State Park: Float Through a Rare Forest 

Caswell Memorial State Park started from a gift from the Caswell family to preserve the mature riparian oak woodland found within the park from encroaching development. Here, visitors can float through willows alongside the Stanislaus River or camp among cottonwoods, experiencing a living window into the San Joaquin Valley of long ago. California State Parks is currently performing trail restoration work and installing campfire center improvements, ensuring that future generations can discover the same sense of refuge and relaxation that inspired the park’s creation. 

Dos Rios: The Next Chapter of the Valley’s Legacy 

A new chapter unfolds at Dos Rios. Purchased through a partnership in 2012, River Partners and the Tuolumne River Trust spent more than a decade transforming working ranchland into restored floodplain forest. More than 350,000 native trees and plants now take root across eight river miles, causing birds (and birdwatchers!) to flock to this park at the confluence of the San Joaquin and Tuolumne rivers.   

The park opened to the public for day use in 2024 with guided tours, picnic areas, and educational programs. The 3-acre Native Use Garden preserves culturally significant plants in perpetuity, ensuring Native peoples have continued access to materials for ceremonies, food, medicine, and traditional arts such as basket weaving. In 2026, a new welcome center will open with expanded public gathering space.  

Great Valley Grasslands State Park: Restoration Continues in the Wetlands

Great Valley Grasslands State Park protects over 2,800 acres that contribute to California’s largest contiguous wetland block. Current work in the park includes breaching levees that no longer serve a purpose, allowing the San Joaquin River to move more naturally across its historic floodplain. This reconnects fish to spawning grounds and restores wetlands and native grasslands while strengthening resilience in the face of future floods. Visitors can take a day trip through this park using the Fremont Ford small boat launch or by walking along the unpaved roads, where wildlife and seasonal wildflowers are common sights.   

Find Your Place: These Parks Await You 

Enjoying these parks is simple. Share the space with other visitors and with the plants and animals that rely on it. Come with curiosity, take time to observe, and immerse yourself in the landscape. “These places have special meaning to the plants and animals that call them home and to the humans that call them a home away from home,” says Haller. 

In a region where protected land is scarce, these river parks carry a responsibility far greater than their size. They are windows into the past, anchors in the present, and living investments in the future — inviting every visitor to step in, look closely, and see what thrives when rivers and people have room to breathe. “When people discover these places, they love them and want to keep coming back,” says Gerhart.  

Parks for the People: Make Your Mark 

Both first-time visitors and familiar faces have the opportunity to chart a course for the future of these parks. Dos Rios and Great Valley Grasslands are currently undergoing the general plan process, a crucial step that allows permanent improvements to be made. “Our goal is to build these parks with the community, not just for the community,” says Gerhart. “These are public places, and we value input.”