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Flood Defense Group Protects Oil & Gas Facilities in Louisiana from Mississippi River Flooding And Modifications to a HESCO Bastion Floodwall

This is a site that required aversatile flood barrier capable of allowing existing pipework to transition through it while also tying the barrier into and a sloped embankment.  Additionally, this project needed to be 8’ tall and capable of being left in place for a number of years without significant maintenance requirements.

HESCO Bastion was the clear flood protection system of choice in this project for a variety of reasons.

  • HESCO Bastion easily stacks to achieve 8’ in protective height
  • HESCO Bastion offers robust protection against flood waters and the power of the Mississippi River
  • HESCO Bastion is easily modified to conform around existing pipework
  • HESCO Bastion can be left in place for many years with minimal maintenance
  • HESCO Bastion is the most economical and effective option on the market in achieving greater heights of flood protection which can easily be built higher at a later date as required

Below are some of the features of this project

How to build a flood barrier around pipes using HESCO Bastion

We enjoy working with this product in difficult locations such as this because it is easy to modify for a good fit when the situation requires. In this example, the barrier had to transition through the pipes pictured and into the berm on the left side of the photo.

Step 1 – We started by placing a unit of HESCO Bastion on either side of the pipes as seen in the photo to the left and the photo below.

Step 2 – Wire the two units together around the pipes to be sealed. This can be done in a variety of different ways but in this example, we did the following

A) We cut two strips of a single square strip of the welded wire mesh and attached it vertically to the HESCO Bastion units on either side of the pipes as shown
NOTE:  These strips allow you working space and an anchor point for step B

B) We then cut strips of welded wire mesh which were transitioned from side to side and between the pipes

C) Use a coil on either side of the pipes to screw the vertical and horizontal wire panel pieces together therefore connecting the HESCO Bastion on either side and between the pipes.

Step 3 – Line your modified cell with geotextile fabric and carefully fill the dirt/sand up and around the pipes making sure the geotextile forms a complete seal around the pipe and that fill material cannot escape. Compact the fill material in 1’ lifts throughout the filling process.
NOTE: We normally do not use water to create compaction but in this case, we did use water to ensure the sand was consolidated and well compact around the pipes throughout this cell prior to stacking the 2 layer high HESCO Bastion.

Step 4 – Spray Foam Seal for Good Measure
In this case, because of the number of pipes, we felt a layer of spray foam around the point of entry of the pipes into the HESCO Bastion was a good idea as foam is a great tool in sealing up areas where seepage may occur during a flood event.
NOTE: Don’t forget, Spray Foam is a wonderful tool in sealing up gaps that may occur within your flood defense perimeter!

How to tie a HESCO Bastion floodwall into an earthen embankment?

Normally, there are two common methods of doing this.

  • Dig a keyhole into your berm and backfill around your barrier upon completion
  • Modify the HESCO Bastion by cutting it down to size such that it appears to disappear into the berm without digging into the berm at all

In this case, we went with option 2 and modified the HESCO Bastion to conform it to the earthen berm. This is easily done by taking a new unit of HESCO Bastion and completely disassembling it. This will allow you to modify/cut the material and reconnect it one cell at a time while you conform it to the embankment you are tying into.

We did this because there was a lot of vegetation (root structures) within the berm as well as a layer of seashells on the surface of the berm which are all great additions to prevent erosion of the berm during a flood event. Digging into a berm creates a vulnerability for erosion and we were happy not to disturb the existing soil/berm

NOTE: Freshly disturbed dirt is prone to erosion from moving water during a flood event. This is also why we did not want to dig into the berm. If you ever do dig into a berm and have freshly disturbed soil, it may be wise to cover it with stone which is helpful in preventing erosion from floodwater during a flood event as water starts swirl around the area.

Create additional stability or support for your HESCO Bastion Floodwall

It is simple and inexpensive to install ‘buttress walls’ or ‘buttress cells’ to a line of HESCO Bastion for added stability as desired. The photos above show how we were able to take a few cells and attach them to main line of HESCO Bastion close to where the floodwall ties into to an earthen berm on either side of the facility being protected for some easy reinforcement at this tie-in point.
Perhaps this could be considered ‘overkill’, but the speed and ease associated with simply adding some buttress cells along the way gives us added comfort when floodwaters arrive and are near the top of your barrier! This buttress cells can be added during construction or even years later as desired.

Conclusion: HESCO Bastion was a great fit for this location and the description of our modifications to the HESCO Bastion product during construction detailed above are designed to give possible end users an idea of product capability should you have a similar situation. We understand that modifications of HESCO Bastion (or any flood defense barrier) voids any manufacturers warrantee associated with the product and ‘done at your own risk’. We regularly modify the HESCO Bastion product if/when required to suit the location with great and continued success which is always up to the client or the end user to endorse as we do not assume liability for the final outcome of any project. This description of for general knowledge and understanding of our work with the HESCO Bastion product which may prove helpful during the evaluation of this product for potential end users. It’s an amazing product which is extremely versatile!