Build a Log Bridge

Here is a minimally disruptive method of building a log bridge across a stream.

| February/March 1994

Outside of a drought or miracle similar to the crossing of the Red Sea, there is no way to make a dry crossing over a body of water without a bridge. I desperately needed one to cross the Class One stream on our property in the western Cascades of Oregon. So I decided to build a log bridge, one that would meet my needs without causing damage to the environment.

The first thing I did was take a trip to the area State Forest office and make a request for a bridge-building permit. That was followed by an on-site inspection by the local forester, who decided the stream banks were level enough so that water drainage from a road wouldn't flow down onto a bridge and into the stream.

The permit explained the two best methods of moving logs across a stream without harming the stream bed. The method I selected, explained below, involves an elevated-cable system, a truck winch, and an anchored-log tripod with a cable pulley. This allowed me to haul logs across the stream without touching the stream bed at all.

The other (more costly) method is to use a large backhoe to lift the logs across the stream. According to the permit, we were also responsible for reseeding those areas along the roadway and bridge that were disrupted by our machinery. The whole process was so simple and turned out so well that I drew up some plans and diagrams to share with you.

Bridge Construction

Begin by finding (or, if necessary, hiring) someone with a portable saw mill to saw planks for the bridge deck. We had a friend cut forty 3 x 12s, sixteen 2 x 12s, and seven 4 x 6s. Cut down and limb just enough cedar trees to make six 42' span logs (which run across the stream) and two 12' bunker logs (which hold up the span logs).

Place the larger of the two bunker logs in a shallow trench on the accessible side of the stream (the side you're standing on); you may have to dig a trench if a natural one doesn't exist. Level the top. Next, position long but narrow logs across the stream, allowing the top ends to rest on the bunker so that they form a ramp. Using the ramp, roll the second bunker log to the far bank.

mother earth news fair 2018 schedule


Next: September 14-16, 2018
Seven Springs, PA

Whether you want to learn how to grow and raise your own food, build your own root cellar, or create a green dream home, come out and learn everything you need to know — and then some!


Subscribe Today - Pay Now & Save 64% Off the Cover Price

Money-Saving Tips in Every Issue!

Mother Earth NewsAt MOTHER EARTH NEWS, we are dedicated to conserving our planet's natural resources while helping you conserve your financial resources. You'll find tips for slashing heating bills, growing fresh, natural produce at home, and more. That's why we want you to save money and trees by subscribing through our earth-friendly automatic renewal savings plan. By paying with a credit card, you save an additional $5 and get 6 issues of MOTHER EARTH NEWS for only $12.95 (USA only).

You may also use the Bill Me option and pay $17.95 for 6 issues.

Canadian Subscribers - Click Here
International Subscribers - Click Here
Canadian subscriptions: 1 year (includes postage & GST).

Facebook Pinterest Instagram YouTube Twitter flipboard