Silt Control with Bubble Curtain in London

4-lines-of-bubble-tubing-single-compressor-in-new-river

 

Bubble Tubing® was recently used to prevent silt pollution from travelling downstream in the New River, East London during essential bank stabilisation works that installed several hundred meters of steel sheet piles.

The project was critical to protect a key drinking water abstraction.

These works were undertaken on behalf of Thames Water by MWH Treatment, a member of the eight20 alliance and responsible for delivering 1.75bn of capital works in the water sector during AMP6.

Collapsing bankside on New River risked impinging the waterway

Collapsing bankside on New River risked impinging the waterway

In-channel works such as dredging and bank stabilisation stirs up silt, leading directly to the suspension of sediments within the water column.

This can cause silt pollution downstream, directly impacting wildlife & habitat as well as being detrimental to water abstractions.

For the duration of the project, 4 lines of Bubble Tubing®, powered by a single, silenced compressor were used to create a bubble barrier that prevented the movement of silt downstream.

4 lines of Bubble Tubing powered by a single compressor were used to control silt pollution

4 lines of Bubble Tubing powered by a single compressor were used to control silt pollution 2

4 lines of Bubble Tubing powered by a single compressor were used to control silt pollution

The river banks were too weak to support heavy, land-based plant so a floating piling rig was used to drive the new piles from the water. The project had to be undertaken quickly and efficiently to minimise the risk of over-running and the potential to disturb roosting bats.

The bubble barrier was the ideal pollution control tool as it could be re-positioned quickly and easily to remain in front of the piling line and control the fine suspended particles generated from the activity.

As part of the bubble curtain package an oil free, silenced, electric compressor was supplied to provide compressed air to the bubble barrier, with no disturbance to local residents or risk to the environment.

The bubble barrier also aerated the water column, an added benefit that reduced the risk of low oxygen levels, often associated with muddy water impacting on the fish populations.

The project was completed successfully and on schedule.

Independent research undertaken by SEACAMS has shown Bubble Tubing® can control 90% of silt particles down to 63 microns. The New River project indicates that smaller silt particles associated with London clay can be controlled in a low flow environment.

frog environmental are actively engaged in research and product development to prevent silt pollution and improve water quality.

Key Stats

  • 4 lines of Bubble Tubing®
  • Oil free air compressor
  • London clay was controlled