Road Construction & Placement
One way to control water on a road system is to ensure that the road is constructed in a way that safely and efficiently sheds water from its surface. When constructing a road, pay close attention to the topography, soil types, and drainage patterns. You can then use techniques such as crowning and ditching, outsloping, and removing trees along the road to facilitate drying as the site dictates.
The main goal is to direct the surface runoff water off the road’s surface quickly, while providing for safe and efficient vehicle travel. Water diversion structures should direct water to undisturbed forest floor and should never direct water to streams or other water bodies.
A logger is planning the best route through the logging site. He’s decided on four options. The first two are not ideal choices. Let’s find out why.
The blue line indicates a very poor choice for a road location because this location provides limited access to the entire tract. This road would more than likely be placed in a low wet area of the tract, raising concerns over ponding and rutting issues. It may also be located within the SMZ. This location would probably have significant impacts on water quality.
The yellow line would also be a poor location for a road. It provides greater access to the tract, but it crosses the stream twice and also uses drainages as part of the road system. This location could certainly have significant impacts on water quality.
Now, let’s add in a third choice and see why it’s a good choice, but not quite ideal.
A road located along the green line has good access to the tract, while also limiting its impacts on water quality on the site. Notice that there is only 1 stream crossing, it stays along the ridge tops as much as possible, goes around the head of drains, and is placed at locations where the slopes are more gentle.
Finally, let’s look at one more road placement.
The placement of the roads highlighted in black is ideal. It has good access to the tract while also limiting its impacts on water quality on the site. Notice that there are no stream crossings due to obtaining backside access, it stays along the ridge tops as much as possible, goes around the head of drains, and is placed at locations where the slopes are more gentle. Of all the options, this is the best.
We’ve looked at the types of forest roads, permanent and temporary roads, water control structures, and road construction and placement. It’s time to take the quiz for this section. Click Forest Roads Quiz in the box below.