You can construct bridges in a garden for decoration or practical purposes. Carefully structure any bridge that has to support weignt with proper footings and materials. Using a bridge in the landscape can not only support simple foot traffic, but it can add the element of intrigue to the design of your garden.
Building structures into your garden can make a major difference to the look of your landscape. Even smaller events like sheds, rocks and boulders or bridges can make the garden into something special. A small ornamental bridge can be an asset to any landscape. It can lead from one area to another, cross a stream or gully, create a lead-in to a focal point or become a focal point in itself. You can buy a small garden bridge or build one yourself. Here are some basic directions to build your own bridge. Feel free to vary the form and design according to your tastes.
Cut a simple wooden base. The base can be curved or flat depending on whether you want an arched or flat walkway. Design rails to be fancy or basic. You can use all kinds of materials to make your bridge ornamental, but here is a basic design for a wooden bridge that you can work with and amend your design to fit your taste
Using redwood or cedar are likely to give you the best wear in outdoor conditions. Green wood is also long-lasting, but if you plan to use your bridge near to any edible gardens, the chemicals used as a preservative in the green wood might leach into the surrounding soil. This may or may not be a health concern: toxicity of green wood is still under debate.
Cut base boards. Minimize the amount of wood that will come in direct contact with the ground to keep as much wood dry and clean as possible for longevity
Measure and cut uprights.
Fill imperfections, holes and chips.
Use Galvanized carriage bolts, hex nuts and washers instead of zinc so you can replace any parts more easily over time.
Try all pieces out before gluing or drilling to make sure all the pars fit right.
Touch up any paint or stain areas that have become scraped or scratched during assembly.
Painting your bridge with an overall coating of waterproof sealer will make it last longer, especially when exposed to outdoor moisture and temperature changes.