Erosion Control Tube: An Overview

An erosion control tube (often called a silt sock or filter sock) is a flexible, 3-D tubular mesh device filled with filter media that slows and redirects stormwater runoff while filtering sediment. In plain terms: it’s a portable “mini berm” that helps keep muddy water from leaving the work area and protects sensitive points like inlets, slope toes, and flow transitions.

What an Erosion Control Tube Is (and What It Isn’t)

Erosion control tubes are used to intercept and manage runoff. They can act like a small check structure (to slow water), or like a low berm (to guide water away from vulnerable areas). They’re commonly used around inlets, along perimeters, and on slopes where sheet flow needs to be broken up.

How It Works: Slowing Flow, Spreading Runoff, Filtering Sediment

When rain hits bare soil, runoff gains speed and starts carrying fine particles (silt and clay). Erosion control tubes help by:

• Reducing velocity: slower water carries less sediment and causes less scour.
• Creating a small ponding zone: sediment has a chance to settle out before water continues.
• Spreading flow: interrupting sheet flow on slopes reduces rills and gullies.

Photo 1: Erosion control tube used for runoff diversion

Practical example: “divert first, filter second”

On many sites, the biggest win is redirecting runoff away from freshly disturbed soil or a vulnerable edge. Placing the tube on contour (slightly angled to steer water) can move runoff toward a stabilized outlet while still filtering sediment along the way.

Field tip: avoid creating a straight “dam” across a steep slope unless the design calls for it—controlled relief points help prevent overtopping and washouts.

Best Applications for Erosion Control Tubes

1) Slope interruption (contour wattles)

• Breaks up sheet flow to reduce rilling and gully formation
• Creates manageable “steps” that slow runoff and trap sediment

2) Perimeter and downslope protection

• Helps keep sediment from leaving the work zone
• Useful where silt fence install is difficult or temporary layouts change often

3) Inlet protection and sediment traps

• Forms a ring or horseshoe upstream of inlets to reduce sediment entry
• Can be layered/stacked when additional capacity is required (per plan/spec)

4) Ditch checks and low-flow control (when appropriate)

• Can slow low-to-moderate flows in shallow channels
• For high-velocity channels, engineered check dams or lined conveyance may be required—follow project specs

Photo 2: Erosion control tubes installed on a hillside (contour placement)

Placement concept that works

On slopes, tubes are typically placed on contour (following the elevation line) to interrupt sheet flow. This reduces the “runway effect” where water accelerates downslope. The result is less erosion, less sediment movement, and fewer repairs after storms.

Practical planning tip: the steeper/longer the slope, the more frequently you generally need interruptions. If the project has a SWPPP or engineered plan, use that spacing and layout as the source of truth.

How to Choose Size and Layout

Tube diameter and layout should match runoff volume, slope length, and how much sediment you’re trying to control. This guide focuses on an 8" × 200' tube—a common “workhorse” size for jobsite runoff diversion and sediment control.

Quick selection logic

• 8" diameter: versatile for general perimeter control, inlet rings, and slope interruption in many typical site conditions.
• Larger diameters: useful when flow volumes are higher or longer run lengths need more capacity (per plan/spec).
• Long runs (like 200'): reduce the number of seams and connection points—often a reliability upgrade.

Step-by-Step Installation

1) Identify the problem you’re solving

1. Diverting runoff? Identify the safest path and where the water will go (outlet planning).
2. Protecting an inlet? Confirm you’re not blocking overflow relief and that water can still reach the drain.
3. Stopping slope erosion? Mark contour lines and note concentrated flow points.

2) Prep the surface

1. Remove large rocks and debris so the tube can sit tight to the ground.
2. Grade out obvious gaps—water will find the gap and bypass the BMP.
3. In higher-flow conditions, cut a shallow trench so the tube “keys in” and reduces undercutting.

3) Place and shape the tube

1. Lay the tube along your marked line (contour, perimeter, or inlet ring).
2. Keep it in continuous contact with the ground—no daylight under the tube.
3. If connecting sections, overlap ends and secure per project guidance.

Photo 3: Setting up and staking erosion control tubes on-site

4) Stake it so it can’t migrate

Stake spacing depends on slope, soil, and expected flows. The goal is to prevent rolling, sliding, or water lifting the tube during storms. Place extra stakes at ends, overlaps, and any curves where water pressure concentrates.

5) Build in controlled relief (when diverting water)

If you’re diverting runoff, avoid sending it to an unstable area. Use a stabilized outlet approach (stone, pad, or designed discharge point) so you don’t solve one erosion problem by creating another.

Inspection & Maintenance Checklist

• After rain events: check for bypassing (water cutting around ends) and undercutting (water flowing under the tube).
• Remove sediment buildup: when accumulation reduces capacity or causes overtopping.
• Fix gaps immediately: small gaps become the “preferred path” for concentrated flow.
• Confirm inlet function: inlet protection setups must still allow drainage—never permanently block storm drains.

Case Study: Hillside Diversion That Reduced Washouts and Sediment Tracking

What was installed

• One 8" × 200' erosion control tube installed on contour as a mid-slope interruption.
• Additional short sections used to guide runoff toward a stabilized discharge path.
• Stakes placed at regular intervals with extra anchoring at ends/curves (per site conditions).

Why it worked

1. Velocity reduction: the tube interrupted sheet flow, reducing rill formation.
2. Better flow direction: runoff was guided away from the drive edge where sediment was tracking.
3. Faster maintenance: crews could remove trapped sediment and re-set alignment without rebuilding an entire fence line.

Outcome

The slope showed fewer new erosion channels after storms, sediment accumulation was more localized (easier to clean up), and the access drive stayed cleaner. Once permanent stabilization went in, the tube was removed or relocated as needed—keeping the site flexible during active construction.

FAQ: Erosion Control Tubes (Silt Socks / Filter Socks)