Appendix B: Bioengineering for Streambank Erosion Control -- Guidelines
and installing the willow posts plus the other operations mentioned above, e.g., shaping site,
cedar tree installation.
Vegetative Geogrid
Man-hour costs for 123 ft of a 6-ft high vegetative geogrid installed on the Upper
Truckee River that was previously mentioned included the following:
Three days time of:
1 foreman/equipment operator
1 equipment operator
2 laborers
1 supervisor/project manager
Thus, 120 man-hours were expended on the above project assuming an 8-hr day. This
equates to about 1 manhour per linear foot of treated bank. About 66 percent of the costs
of this treatment can be attributed to labor.
Man-hour Costs of Standard Vegetation Establishment Techniques
to Supplement Bioengineering Treatments
Standard Seeding
The cost for broadcast seeding per square metre can vary considerably according to some
literature sources. Reported costs in man-hours per square metre vary from 0.004 (Kay,
1978) to 0.07 (Schiechtl, 1980) depending on the degree of slope and the type of seeds used.
Hydroseeding
Depending on the material used and the distance to adequate water, 4,000 to 20,000 sq
m can be hydroseeded by one hydroseeder machine per day (Schiechtl, 1980). A hydroseeder
normally uses a two-man crew.
Hydromulching
Mulching is often applied over seeds by a hydromulcher similar to a hydroseeding
machine. For hydromulching or mechanical mulching without seeds, about 0.12 to 0.50 man-
hours per square metre is estimated (Schiechtl, 1980). Mulching after seeding increases the
cost per square metre considerably. Hydromulching with a slurry of wood fiber, seed, and
fertilizer can result in a cost of only 0.008 man-hour per square metre, according to
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