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    Climate and Sustainability Action

    Sustainable Roads, Bridges and Dams

    State parks and forests are experiencing more frequent and intense storms, and the infrastructure that supports roads, trails, and visitor access must be adapted to these changing conditions. Sustainable infrastructure prepares these landscapes for heavier rainfall, stronger floods, and shifting weather patterns by designing culverts, bridges, and drainage systems that can handle larger storm events and fluctuating water levels. This approach improves public safety, protects natural resources, and ensures long term resilience as the climate continues to evolve.

    Right Sizing Culverts and Bridges

    Undersized culverts and bridges can restrict stream flow, causing water to back up during heavy rain events. When crossings are too small, they may lead to:

    • Road overtopping
    • Bridge scour and structural damage
    • Streambank erosion
    • Road washouts and emergency repairs

    To address these risks, the Pennsylvania Department of Conservation and Natural Resources (DCNR) is replacing outdated crossings with larger, flood-resilient, and ecologically sensitive structures across Pennsylvania state parks and forests.

    Modern Engineering for Changing Storm Patterns

    DCNR’s Bureau of Facility Design and Construction designs new culverts and bridges using contemporary hydrologic models. These models evaluate:

    • Historical rainfall data
    • Updated flood frequency information
    • Projected increases in storm intensity

    This approach helps ensure new infrastructure can handle today’s storms — and potentially stronger storms in the future due to climate change.

    Benefits of Upsized Culverts and Bridges

    Increased Flood Capacity: Larger crossings allow streams to pass higher volumes of water and debris safely. This reduces the likelihood of road overtopping, bridge scour, and structural failure during major storm events.

    Improved Fish and Wildlife Passage: Modern culvert designs are constructed to better mimic natural stream conditions. This helps maintain natural stream slope and channel shape, improve aquatic organism passage, and reduce habitat fragmentation.

    Long-Term Resilience: By designing for larger flood events instead of outdated historical norms, DCNR is strengthening park and forest infrastructure against increasingly intense storms.

    Infrastructure Improvements Across State Lands

    As part of its infrastructure modernization efforts, DCNR has constructed 100 improved culverts and bridges on state park and forest lands from 2020-2026. These upgrades help:

    • Keep people safe
    • Maintain access to parks and forests
    • Reduce long-term maintenance costs
    • Support healthy stream ecosystems

    Case Study: Tuscarora State Forest

    Installed in 2024, a new box culvert was placed on Laurel Run Road over Cold Spring Run in Tuscarora State Forest. It is 10 feet wide and has a 4‑foot rise. It replaced an older metal pipe that was only 5 feet wide. The new structure is twice as large as the old one, which helps more water flow through safely.

    A small stone‑faced box culvert sits beneath a gravel and leaf‑covered roadway area in a forest of tall, leafless trees. The culvert opening is surrounded by rocks and slopes gently downward toward a dry, leaf‑covered streambed. A wooden guardrail runs along the road above the culvert, and the forest extends into the background.

    Inside the culvert, the streambed was rebuilt to look like the natural stream, including features like pools and riffles. Because the culvert is wider and has these natural features, fish and other aquatic animals can move through it more easily. The culvert was also designed to handle a major storm, known as a 100‑year flood, without water flowing over the road.

    It also includes an updated fish baffle. This helps keep a small, steady channel of water flowing so fish can pass through without realizing they are traveling under a road.