Restoring Stream Connectivity in Arkansas

But these connections are fragile. Across Arkansas, thousands of road-stream crossings interrupt the natural flow of streams. Culverts, low-head dams, and fords often fail to accommodate aquatic movement. When these structures block passage, they fragment habitats, isolate populations and degrade water quality. Over time, this can lead to declines in species that define the character and health of our rivers.

Why Connectivity Matters

Imagine a fish trying to reach cooler headwaters during summer heat or a mussel species needing to spread upstream to maintain genetic diversity. If a crossing blocks that movement, the entire population becomes trapped. These barriers also alter stream dynamics, increasing erosion and sedimentation,  which harms and degrades aquatic habitat and reduces water quality for humans and wildlife.

The good news? Solutions exist. Replacing outdated crossings with designs that mimic natural stream conditions—such as full-span bridges or open-bottom culverts—restores connectivity and resilience. While it’s not feasible to replace every barrier, strategic projects can reconnect miles of habitat and reduce flood risks for communities.

The solution was ambitious and collaborative. With funding from the Environmental Protection Agency's Section 319 Nonpoint Source Pollution Program, the Newton County Road Department designed and installed a 100-foot span bridge with a single pier in the channel. This upgrade reconnected six miles of stream to the Buffalo River, opening new habitat for fish and other aquatic species. It also improved flood resilience and reduced long-term maintenance costs for the county.

Newton County took the project a step further by abandoning 750 feet of road that hugged the creek and building a new, well-crowned road on the floodplain terrace. This change reduces erosion and protects water quality. The Arkansas Game and Fish Commission contributed additional funding and provided staff support to stabilize the site with planting and seeding, while TNC facilitated permitting and project coordination.

This project demonstrates what is possible when conservation and community priorities align. Healthier streams, stronger infrastructure, and a future where nature and people thrive together.

This project has been funded wholly or in part by the United States Environmental Protection Agency under assistance agreement C9-996103-28 to Arkansas Department of Agriculture, Natural Resources Division. The contents of this document do not necessarily reflect the views and policies of the Environmental Protection Agency, nor does the EPA endorse trade names or recommend the use of commercial products mentioned in this document.

Restoring Crossings in Stone County

Stone County Roads Department partnered with TNC to remove two aging low-water crossings on the main stem of the Middle Fork of the Upper Little Red River. These crossings, built with undersized culverts, constricted river flow and blocked fish and other aquatic life from reaching vital habitat for feeding and reproduction.

The old culverts were replaced with crossings that are wider and higher, improving vehicle travel and safety while restoring stream connectivity. Each new crossing features larger concrete box culverts with openings large enough to allow natural flow and aquatic passage. In fact, one new culvert now passes more water than all the old undersized culverts combined.

Together, these upgrades restored connectivity to 308 upstream network miles, including 26 miles of the Middle Fork main stem. This means fish and other aquatic species can now access critical habitat throughout the watershed, strengthening populations and improving ecosystem health.

Who Manages Our Gravel Roads?

Improving stream connectivity starts with understanding who manages the thousands of road-stream crossings across Arkansas. The primary responsibility falls to county governments, led by County Judges and County Road Departments. These teams maintain extensive networks of gravel roads that often intersect streams in the Interior Highlands.

More than 85 percent of Arkansas county roads are unpaved, according to the Arkansas Unpaved Roads Program, which means counties face a monumental challenge. Many crossings are decades old and beyond their functional lifespan. Updating them to meet modern transportation needs and withstand increasingly severe floods is no small task.

Counties are not alone in this work. Timber companies and state and federal agencies also manage public gravel roads where they cross streams on their lands. Each plays a role in maintaining safe infrastructure while protecting water quality and aquatic habitat.

TNC is partnering with these road managers to bring in funding and technical support. By leveraging federal and state resources, we help counties replace outdated crossings with designs that improve flood resilience and restore aquatic connectivity. These projects reduce long-term maintenance costs, protect local communities, and reconnect miles of stream habitat for fish and other wildlife.

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