Technical Bulletins

Library of Center publications detailing specific "Environmentally Sensitive Road Maintenance" Practices. Each bulletin is grouped by topic area and is specific to one practice.


  • Headwalls and Endwalls (0.98 MB): General information on the benefits of headwalls and endwalls at pipes (1/19)

  • Stacked Stone Headwalls (372 KB): Details on how to construct headwalls and endwalls out of native stone (1/19)

  • Crosspipe Installation (726 KB): Important considerations and a walkthrough of a typical crosspipe installation. (1/19)

  • Shallow Crosspipe Installation (1.04 MB): Installing pipes based on outlet elevation, not road elevation, to eliminate outlet trenches. (1/19)

Sub-surface Drainage

  • French Mattress (1.09 MB): French mattresses allow water to pass under a road through coarse stone. (1/19)

  • Underdrains (437 KB): General information on underdrain and where and why to use it. (1/19)

  • Constructed Stone Underdrains (1.17 MB): Walkthrough of creating your own underdrain with of perforated pipe, clean stone, and fabric. (1/19)


  • High-Water Bypass (1.07 MB): Hardened overflow area where water can safely flow over road during extreme events. (2/19)

Driving Surface Aggregate (DSA)

  • DSA (717 KB): A summary of the Center-developed DSA. Includes material specification, sampling and testing, preparation for placement, placement, compaction, maintenance, and other considerations. (1/21)

  • Road Aggregates 101 (364 KB): A summary of size, gradation, and typical use for some of the more common aggregates for road maintenance in Pennsylvania. Includes course aggregates and rip-rap. (1/21)

  • Trail Surface Aggregate and general Aggregate Information: Visit the DSA information page

Stream Crossings

  • Bankfull Width Determination (1.75 MB): Guidance and examples for determining the bankfull width of a variety of stream types in Pennsylvania. (7/22)

  • Site Assessment (795 KB): Guidance for conducting a longitudinal profile and cross-sectional survey to determine channel slope and other characteristics to guide project design. (7/22)

  • Structure Selection for Stream Crossing (3.4 MB): Guidance and “pros and cons” of various common stream crossing structure types. (7/22)

  • Grade Control (1 MB): Guidance on the use, design, and installation of large rock or other structures that are immobile in the channel and set the slope and form of the stream. (7/22)

  • Streambed Restoration (2.03 MB): Guidance on the re-establishment of streambed material through a new crossing structure and the reconstructed reach of the stream. (7/22)

Surface Drainage

  • Surface Drainage Practices (655 KB): Road maintenance features designed to shed water from the travelway, including crown and cross-slope, grade breaks, and broad-based dips. (1/19)

  • Crown and Cross-Slope (746 KB): Different types of crown and proper cross-slope for unpaved roads. (3/19)

  • Grade Breaks (620 KB): Grade breaks are surface drainage features that stop concentrated flow and road erosion. (2/19)

  • Broad-Based Dips (600 KB): Surface dips that transport water across the surface of a low volume road. (2/19)

  • Conveyor Belt Diversion (857 KB): Used conveyor belts embedded in the road to prevent water from flowing down the road. (2/19)

  • Surface Maintenance (750 KB): General information on maintaining unpaved road surfaces. (2/19)

  • Raising the Road Profile (1.15 MB): Raising the elevation of the road to achieve better drainage. (3/19)

Road Surface Maintenance

  • Carbide-Tipped Blade (2.27 MB): Benefits of a carbide-tipped blade for surface maintenance operations. (2/19)

Road Banks

  • Bank Benches (604 KB): Steps created in a road bank to slow and control the flow of water over the bank. (1/19)

  • "Through-the-Bank" Pipes (762 KB): A pipe placed through the downhill road bank to get water out of the road profile. (2/19)

Photo Tips

  • DGLVR Photo Tips (429 KB): Informational bulletin for taking more effective project photos for use in education and outreach efforts for the Program. (3/19)