2026 Iowa State Research LP

Key Findings from Iowa State’s Gravel Road Rehabilitation Research

Read this overview of Iowa State University’s findings on aggressive gravel road rehabilitation and Perma-Zyme soil stabilization performance through freeze-thaw conditions.

1. Why Gravel Roads Continue to Deteriorate

Over time, traffic, weather, and repeated maintenance cycles can flatten road crowns, widen roadways, reduce drainage effectiveness, and accelerate surface failure. According to Iowa State researchers, these conditions increase maintenance demands and long-term costs.

2. What Iowa State Studied

The study evaluated aggressive rehabilitation methods on heavily deteriorated gravel roads, including:

• Restoring proper road width and crown

• Rebuilding drainage profiles

• Different compaction methods

• Perma-Zyme's performance over two freeze-thaw cycles

Perma-Zyme being sprayed onto subgrade with a water truck

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Improved drainage and road performance

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Increased strength and hardness values

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Less visible surface deterioration

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Consistent performance through freeze-thaw conditions and heavy loading

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Proper road shape and drainage played a major role in long-term performance

4. Why This Matters for Counties

The research reinforces the importance of restoring proper drainage, maintaining road shape, and implementing long-term stabilization strategies with Perma-Zyme instead of relying solely on repeated grading cycles.

The study also showed that Perma-Zyme can be applied using equipment commonly available to county road departments.

Key Findings from Iowa State’s Gravel Road Rehabilitation Research

1. Why Gravel Roads Continue to Deteriorate

2. What Iowa State Studied

3. Key Results Showing the Performance of Perma-Zyme Treated Roads:

4. Why This Matters for Counties

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