Joints should be tight as practicable and, if possible, covered with some type of sealing materials (such as
asphalt or tar) to prevent the water seepage through the joints.
Logs can be used for expedient culvert and if properly constructed should function until replaced by a permanent
structure. For capacity, the end area should be equivalent to CMP for the same slope. In constructing log culverts
remember these things:
To obtain structural strength, the logs should be trimmed where required to ensure proper seating, and
securely fastened with spikes or drift pins.
Lay the logs butt to tip to reduce the joint openings.
Caulking with leaves and brush and sealing the openings with asphalt will reduce the movement of water
into the fill.
To prevent the movement of soil through the openings, double-layer or cover the top logs with burlap or
brush.
Expedient culverts can be constructed of sand bags bridged with either pierced steel planks or logs. The deck
should be covered with burlap or brush to seal openings and prevent loss of soil.
Oil, gasoline, or asphalt drums can be used for expedient culverts. The capacity of these culverts can be taken as
equivalent to the same diameter CMP set on a similar slope.
Remember to provide cover of a minimum of three feet over culverts of this type. When drums are used, care
should be taken to remove the top and the bottom. Be cautious when cutting out the ends with a cutting torch if
the drum contained flammable material. The joints between the drums should be fully welded. If this cannot be
done, some provision should be made to seal the joints to prevent the culvert water from saturating the fill.
WARNING
Using a torch to open drums is not recommended.
PART C - CULVERT PLACEMENT IN DITCH DESIGN
ALIGNMENT
The relationship of the culvert to the bed of the stream is of major importance. Improper location can cause the
stream to seek a path other than through the culvert, and the project may be destroyed. Certain techniques can be
used to lessen the probability of this occurring, such as the following:
Place the culvert directly in the stream bed, (see figure 5-5(a)) even though it may be diagonal to the structure. If
no change is made in the hydraulics of the channel, the stream will not change its direction.
EN5465
5-6
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