A . Boardwalks and Bridges
Boardwalks are used to connect trails over environmentally sensitive areas . Boardwalks are typically made of wood timbers , recycled composite plastic , or narrow liner concrete slab . If properly constructed , boardwalks minimize impacts to sensitive areas and can be a good alternative where extensive grading is required ( Figure 7.63.4 ).
Design Criteria :
• Boardwalks to conform to ADA and City of Arlington ’ s Design Criteria Manual standards .
• Railings are required when boardwalks exceeds 30 inches in heightabove the ground surface .
• Boardwalks to meet bridge structural design standards and be designed with pedestrian loading . Where maintenance and emergency vehicles may be expected to cross a boardwalk , the design should accommodate them .
• Identify floodway and floodplain elevations to determine the height at which the decking can be constructed . Verify with local government authorities prior to construction .
• Refer to bicycle and pedestrian bridge section for railing height standards ( Figure 7.63.5 ).
• Environmental and wetland impacts should be minimized when boardwalks are used .
• Use wood products that are environmentally sensitive and nontoxic to the environment .
• Auger piers are preferred for greater support and durability over wood post foundations .
• Interpretive signage should be provided .
• Materials used to construct boardwalk should be contextually appropriate .
• Lighting may be provided at trailheads .
Figure 7.63.4 . Multi-use trail boardwalk section .
Chapter 7 : Design Guidelines | 7-59