BMPs for Erosion Control for Logging Practices in Ohio

Bulletin 196

Stream Crossings

Figure 21. Culvert stream crossings: culvert slope.

• Inlet set too deep increases the risk of plugging.
• Inlet not deep enough lets water undercut culvert.
• Outlet set too high undercuts road fill and stream bed.

Table 2. Culvert sizing chart.

Recommended Diameters of CulvertsBased on Drainage Area
Pipe Diameter	Area Above Pipe
(inches)	(acres)
12	2
15	4
18	7
21	12
24	16
30	27
36	47
42	64
48	90
54	120
60	160
66	205
72	250
78	350

General Guidelines

1. Avoid stream crossing when possible.
2. There is one best place to cross a stream.
3. Cross streams as far up the watershed as possible.
4. A well-defined channel is a desirable place to cross.
5. Minimize the amount of road that would impact the Streamside Management Zone (SMZ).
6. Use portable bridges when practical.
7. Stream crossings are critical areas that should be restored.

Stream Crossing Design Goals

1. Cross streams at a right angle (90°).
2. Break grade as soon as possible on both approaches*.
3. Armor the stream bottom, and protect the banks from collapsing.

Haul Road Crossings

1. Use a portable bridge when practical (Figure 22A and 22B).
2. Use a culvert if necessary (See Table 2).
3. Gravel should be used to cover temporary culvert placement when necessary; gravel and/or soil is acceptable for permanent installation (Figure 11).
4. When fording a stream, armor both banks and approaches through break in grade or water diversion device*. Armor the stream bottom with gravel unless a solid rock bottom exists. Geo-Textile fabrics and Geo-Cell should be considered for permanent crossings.

Skid Road Crossings

1. Use a portable bridge when practical.
2. Use a culvert or pipe if necessary (see Table 2).
3. Pole wood crossings should utilize long poles with a 6-inch diameter small end to fill channel level with banks; culverts may need to be installed under the wood to facilitate water flow. Not recommended for perennial streams.
4. Utilize standing bumper-trees on both banks when possible to keep wood and logs behind the skidder.
5. Approaches should be stabilized up through the break in grade or water diversion device* to minimize rutting and collapsing of the banks.

Stream Crossing Restoration

1. All stream crossings should be restored.
2. Remove bridge, culvert, soil, and all wood from temporary crossings.
3. Carefully restore stream bottom and banks to original contour where necessary.
4. Water bar or maintain break in grade or water diversion device.*
5. Grade roads to minimize rutting.
6. Seed, fertilize, lime, and mulch all disturbed soil up through break in grade or water diversion device.

* Breaks in grade or water diversion devices should be installed with sufficient filter strip below them to keep sediment from being transported to the stream.

Bridges

General Guidelines

• Bridges are effective ways to keep equipment out of flowing streams.
• Utilize a bridge design that will provide safe access and minimize disturbance to the streambank, channel, and the streamside management zone.
• Use temporary or portable bridges instead of culverts to access areas where permanent structures are not needed.
• Place them so as not to unduly constrict stream channels or impede flood waters.
• Anchor temporary bridges on one end with a cable or other device so they do not float away during high water.
• Install so they can be removed easily and promptly when they are no longer necessary.

Figure 22A. Portable logging bridge installed with skidder.	Figure 22B. Alternative bridge design.
Figure 23A. Pole crossing.	Figure 23B. Pole crossing.