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:
Straw Bale Check Dam Design Limits
Maximum Drainage Area Between Check Dams
Maximum Slope Length
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.
(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.
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).
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