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 Appendix B: Bioengineering for Streambank Erosion Control -- Guidelines
Table 3. Comparisons of actual costs of bioengineering treatments with
estimated costs of traditional erosion control (riprapped revetment) under
similar conditions in same area.
Location & Conditions
Type of Treatment
Costs ($/linear ft)
Court Creek, IL
10-ft bank height;
Dormant post & rock toe
$15.19 (actual)
3.1 fps local velocity;
1V:1H graded side slope
Riprapped revetment
$60.00 (est.)
10-ft bank height;
1V:2H side slope;
1.5 ft total rock thickness,
(0.5 ft bedding material);
300# stone size;
1.5 Ton/ft;
$40.00/Ton delivered & placed
Upper Truckee River, CA
Vegetative geogrid
$104.00 (actual)
6-ft bank height;
4 fps local velocity;
stacked soil lifts
Riprapped revetment
$27.00 (est.)
8-ft bank height (2-ft buried);
1V:2H side slope;
18 sq ft rock/ft;
$20.00/Ton delivered & placed
in this report. Some maintenance costs may be associated with the bioengineering treatment
later in the project life, but these costs will be rather small. In contrast, the traditional
treatment using inert structures, such as riprapped revetment, will have a high construction
cost, a finite serviceable life with an element of maintenance, and then a substantial
replacement or refurbishment cost (Coppin and Richards, 1990). Figure 43, again, illustrates
this cost comparison very nicely (Coppin and Richards, 1990).
Costs are also difficult to compare when strictly looking at currency per unit of measure.
The most common denominator for arriving at costs seems to be labor in terms of person
hours it takes to build and install the particular treatment. Then, material costs and equipment
rental, etc., have to be added onto this. The authors could not document time for all of the
bioengineering methods mentioned in the text, but some man-power estimates are given in
the following paragraphs. Also, man-power costs are given for general applications of
seeding and vegetative plantings to supplement the bioengineering treatments.
B-83
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