Straw Bale Check Dam
What is a Straw Bale Check Dam?
These are temporary sediment barriers constructed of straw bales across very
small drainages.
When is a Straw Bale Check Dam Used?
These temporary structures are used to slow debris flow. They are not
intended to provide protection from large storm events or to control debris
flows in water bodies such as creeks, streams and rivers. Straw bale check dam
design limits are as follows:
| Slope |
Maximum Drainage Area Between Check Dams |
Maximum Slope Length |
| 0-15% |
1 acre |
200 feet |
| 15-20% |
1/2 acre |
100 feet |
| >20% |
not recommended |
|
How are Straw Bale Check Dams Installed?
Bales should be bound with wire or polypropylene twine. Bales bound with
sisal twine are less durable. The bales should be placed in rows with bale ends
tightly abutting the adjacent bales.
Downstream Row
(Refer to Illustrations 1 and 2) Dig a trench across the small channel, wide
enough and deep enough so that the top of the row of bales placed on their long,
wide side is level with the ground.
The tops of bales across the center of the channel should all be level and
set at the same elevation. Place the bales in position and stake them according
to the instructions below.
Upstream Row
Dig another trench across the small channel, upstream and immediately
adjacent to the first row of bales. The trench should be wide enough to
accommodate a row of bales set vertically on their long edge. The trench should
be deep enough so that at least six inches of each bale is below ground,
starting with the bale in the center of the channel bottom. The trench should be
as level as possible so that the tops of the bales across the center of the
channel are level and water can flow evenly across them. Continue this trench up
the side slopes of the small channel to a point where the unburied bottom line
of the highest bale (point “C” on Illustration 3) is higher than the top of the
bales that are in the center of the channel (point “D” on Illustration 3).
Anchorage
Drive two-inch by two-inch stakes or number 4 rebar through the bales and
into the ground 18 to 24 inches for anchorage. The first stake in each bale
should be driven toward a previously laid bale to force the bales together (see
Illustration 3).
What Maintenance is Needed?
Inspect the bale check dam and provide necessary maintenance following each
storm period. Remove the bales, stakes, and wire or twines once permanent
drainage and stabilization is reestablished. Used straw can be used as mulch in
other areas.
Illustration 1: Top View

Illustration 2: End View

Illustration 3: Upstream View

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