How to Build a Bridge Over a Creek
Figuring out how to build a bridge over a creek or stream is much easier than you might expect; you could even use materials found around your chosen location.
Building a Creek Bridge
To start building a creek bridge, just follow these four simple steps:
Making the Foundation
Find the narrowest part of your creek and measure the width. You will need two logs that will reach over the creek; they should be the same size and strong enough to hold a lot of weight. If the logs give any signs of weakness such as cracks or sounds of breakage, then they are not suitable. A simple rule is that logs should be one inch thicker in diameter for every foot in length in order to be strong enough.
Lay the logs across the creek approximately two feet apart, with a foot of log at either bank for added stability. If you are intending on building a bridge wider than two feet then add more logs accordingly. Approximately one extra log for every additional two foot in width should be sufficient.
Raising the Bridge
You now need to raise the bridge so that there is no obstruction to the water flow, increased stability and so that the bridge will not be washed away in heavy storms.
At either end of the bridge, set either a heavy rock or log underneath the logs. Making sure that the logs are completely flat, the logs should now have been raised to exactly the same level.
Attach the Cross-Sticks
Now you will need to find long thick sticks to lie across the log foundation. These should be placed perpendicular to the base logs and no more than an inch apart. They should be able to hold as much weight as required. If unsure of the stability of a stick, the same rule of one inch in diameter per foot in length will work. If the bridge has more than two logs in its foundation then you should align the sticks so that they alternate between each space between the logs.
Using rope or twine, you now need to tie all of the cross-sticks onto the foundation logs whilst ensuring that they do not move or twist under pressure.
When studying how to build a bridge over a creek, you may consider some finishing touches. This step is not completely necessary, however it will mean that the bridge is much more stable, easier to walk on and more enduring. You will need mud or clay which should be thick enough not to slip through your fingers when they are spread apart. Shovel the mud/clay onto the bridge patching any gaps with extra sticks. This needs to be approximately one and a half to two inches thick. Next you need to add a layer of dry dirt, about a two inch layer, over the bridge and compact down with your hands and bare feet, making sure you pack every part. The more dirt the longer it will last and the more stable it will be.