Park at Expo Idaho

The Park at Expo Idaho transforms a former horse racing track into a vibrant, multi-use public landscape where water, ecology, and recreation are intertwined. Located along the Boise River and connected to the regional Greenbelt Trail, the project reimagines an underutilized site into a regional destination that reconnects people with the Boise River through immersive landscapes, nature-based recreation, and restored ecological systems.

At the heart of the project is the restoration of the site’s historic floodplain. Before development, this landscape was defined by braided channels, wetlands, and riparian forests tied to the Boise River. Decades of filling and grading for the racetrack erased these systems, replacing a dynamic floodplain with a uniform engineered landscape. The design reverses this history by lowering the site’s interior to create the Lowlands, restoring both the landforms and ecological processes that once shaped the site.

The resulting 17-acre Lowlands are defined by more than 1.4 miles of perennial stream channels that weave through wetlands, riparian woodlands, and meadows. Repurposed irrigation water and existing drainage flows are redirected into the restored system, where they move gradually across the landscape before returning to the Boise River. Throughout this process, the water is naturally filtered while replenishing groundwater, expanding flood storage, and reconnecting wetland and riparian habitats. The restored floodplain supports a diverse mosaic of native plant communities that reflect the ecological gradients of the Boise River corridor, creating resilient habitat for wildlife.

Trails, boardwalks, overlooks, and bridges allow visitors to follow the water as it enters the park, moves through wetlands and riparian forests, and ultimately reconnects with the Boise River. Seasonal flooding, changing water levels, and shifting plant communities become visible expressions of the landscape’s ecology, transforming hydrologic infrastructure into a shared public experience.

The excavated soil from the Lowlands is repurposed to form the Ridges, a series of elevated landforms inspired by the mountain ranges surrounding Boise. Wrapping the perimeter of the park, the Ridges establish its primary circulation loop while framing the restored floodplain at its core. At their highest peak, they reach approximately sixteen feet above existing grade, allowing visitors at the various lookouts to enjoy views of the Boise foothills. Strategic openings within the Ridges create gateways to the adjacent Expo Idaho fairgrounds, ensuring connection between the two sites.

Embedded within the Ridges are the park’s two anchor destinations—the Nature Playground and the All-Wheel Sports Garden. Concentrating these active program areas within the elevated landscape allows the restored floodplain to remain the ecological heart of the park while raising significant public investments above potential flood hazards. Within the anchor program areas, water extends into the experience of play and recreation. The Nature Playground draws inspiration from the Boise River’s riparian woodlands, incorporating dry creek beds, boulder scrambles, woodland climbing features, and misting elements that echo the forms and processes of the Lowlands. These spaces encourage open-ended, sensory engagement while reinforcing a tangible connection between play and the surrounding ecological systems.

The Park at Expo Idaho demonstrates how landscape can serve as both ecological infrastructure and civic infrastructure. Through the restoration of the historic floodplain and the creation of a complementary topographic framework, the project brings together habitat, recreation, and community gathering within a single resilient landscape. The result is a regional park that celebrates the dynamic relationship between people and the Boise River while strengthening the ecological systems that sustain it.

Technical Information

Total Site Area: 88 acres
Phase 1 Site Area: 47 acres
Restored Floodplain: 17 acres

Plant Communities: Emergent Marsh, Sedge Fen, Wet Meadow, Riparian Woodland, Dry Meadow, Sagebrush Steppe, Upland Forest

Representative Native Species: Black Cottonwood (Populus trichocarpa), Ponderosa Pine (Pinus ponderosa), Idaho Fescue (Festuca idahoensis), Bluebunch Wheatgrass (Pseudoroegneria spicata), Wyoming Big Sagebrush (Artemisia tridentata ssp. wyomingensis)

Sustainability: Floodplain restoration; balanced on-site earthwork; reuse of irrigation water infrastructure; native habitat restoration; resilient, climate-adapted planting communities.