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Silt Barrier: What It Is and How to Choose One | Mainline Materials
Silt Barrier: What It Is and How to Choose the Right One
What a silt barrier is, the silt fence options, and how to pick one
In This Guide
A silt barrier is a physical control that blocks sediment-laden water from leaving a site. The most common silt barrier on land is the silt fence — a woven fabric barrier staked along the contour. The terms silt barrier, silt barrier fence, and silt fence barrier are often used interchangeably for this staked-fabric control.
Quick answer: A silt barrier is any barrier that holds back sediment in runoff. On construction sites, the staked-fabric silt fence is the standard silt barrier.
A silt fence acting as a perimeter silt barrier.
What is a silt barrier?
A silt barrier is a structure that intercepts sediment carried by water. On disturbed land, the silt barrier of choice is a silt fence: permeable woven geotextile fabric stretched between stakes so runoff slows and drops its sediment. The barrier keeps soil on site, which protects storm drains and waterways and supports stormwater compliance.
Land silt barriers (silt fence)
For land applications, a silt barrier fence is installed along the contour with its bottom edge trenched in. Standard versions use wood stakes; wire backed versions add welded-wire mesh for strength on steep or high-flow runs. Because the fabric is permeable, it filters rather than dams, letting cleaner water pass while sediment accumulates behind it.
Choosing the right silt barrier
Match the barrier to the site. The key variables are fabric weight (GSM), fence height, and whether wire backing is needed:
| Site condition | Suggested silt barrier |
|---|---|
| Typical lot, gentle slope | 36 in, 70 GSM standard silt fence |
| Long exposure or heavy runoff | 100 GSM standard or wire backed |
| Steep slope, long run, DOT work | Wire backed silt fence with T-posts |
| Very large site (thousands of feet) | Fabric-only roll with a silt fence plow |
Installing a silt barrier correctly
A silt barrier only works if it is anchored. Trench the bottom edge, set posts on the downhill side, attach fabric on the uphill face, then backfill and compact. Follow the contour rather than running straight downhill, and inspect after each significant rain — clearing sediment before it builds to about one-third of the barrier height.
Not sure which product fits your site? Use the Silt Fence Selector, our free interactive tool under the Resources menu, to answer a few plain-language questions and get matched to the right silt fence, height, and fabric weight for your job.
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Shop Silt Fence Use the Silt Fence SelectorFrequently Asked Questions
What is a silt barrier?
A silt barrier is a control that blocks sediment-laden water from leaving a site. On construction and landscaping sites, the standard silt barrier is a silt fence — a permeable woven-fabric barrier staked along the contour.
Is a silt barrier the same as a silt fence?
On land, yes. The terms silt barrier, silt barrier fence, and silt fence barrier are commonly used for the staked-fabric silt fence that traps sediment in runoff.
How does a silt barrier work?
A silt barrier slows runoff so suspended soil settles out. Because the fabric is permeable, it filters rather than dams, letting cleaner water pass through while sediment accumulates behind it.
Which silt barrier should I choose?
Match the barrier to the site. A 36 inch, 70 GSM silt fence suits typical lots, heavier 100 GSM or wire backed fence suits steep slopes and DOT work, and fabric-only rolls suit very large sites installed with a plow.
How do you install a silt barrier?
Trench the bottom edge of the fabric, set posts on the downhill side, attach the fabric on the uphill face, then backfill and compact. Follow the land contour and inspect after each significant rain.