More Information on Barrier Pipes:
Barrier pipe is used for securely distributing water via contaminated land (brownfield sites) or on building sites with possible future contamination issues, ie: petrol station forecourts.
It consists of a normal internal PE80 or PE100 pipe (for carrying out the water) wrapped in an impermeable aluminium barrier layer (to stop contaminant ingress) and an outer polyethylene protection afterwards. Sizes 25-355mm are available.
What is Barrier Pipe?
Barrier pipe is a reinforced pipe used to protect water supplies against certain types of contaminants from the soil that can degrade standard MDPE pipe and place your water supply in danger. There are different types of barrier pipes available, including ductile iron, plastic-coated copper and multi-layer plastic pipes with a metal layer. The most common barrier pipe used for water distribution pipes includes a polyethylene core surrounded by a protective metal barrier and covered with another layer of polyethylene to act as a protective barrier. This sort of barrier pipe is dependent upon the black/brown stripes along the length of the outer coating of plastic. The picture adjoining reveals a cross-section. The methods of construction of barrier pipe MDPE pipe. Make it more expensive to manufacture than standard water pipe.
Why Use Barrier Pipes Over Normal MDPE?
The metal produces a barrier to permeation of hydrocarbons, such as gas, and protects the water in the core from contamination. Barrier pipe not only provides added security against land that's already contaminated but also protects against any potential troubles. Although innocuous at the time, a simple drip of oil or leak of gas from a vehicle sitting on a driveway can, over time, start to permeate through the floor and a contaminating material could come into into contact with the pipe then contaminates seep through and gets into the water supply.
Each application will be evaluated on its merits. Where no ground condition assessment is provided to support the program, your water authority will make a determination about the support pipe material based on the information on your program and other sources of information available to them. If they determine that the risk is sufficiently high, they'll specify that a suitable barrier pipe must be used. You then have the option to accept the decision or to provide them with a ground condition assessment to provide them with more info.
A further review can be made and may amend their decision. This will definitely incur a delay to your program so you are encouraged to provide a soil report with your application if you have any concerns about your building site. It is important to note that the choice of the barrier pipe material resides entirely with your water authority. You're strongly advised not to lay any pipe work until you've sent your completed application form to your water authority, and spoken to a member of the team to ensure that you your distribution pipe material and diameter is correct. If they ask for barrier pipe to be installed and you install MDPE in your property boundary instead then your water authority can refuse to connect your supply.
When is it Necessary for Barrier Pipe to be Used?
The previous use of the building site will determine whether the land is at risk of contamination and a barrier pipe has to be used. We ask you to provide information about the present and past use of your website to help us understand the risk. The more detail you can provide, the clearer the assessment we can create, and we would welcome additional sketches or photographs of the site to support your application. If the land has been used for some of the following activities, there is a high possibility that contaminants are present in the ground which could harm or permeate plastic water pipes:
- Railway yards
- Petrol stations and/or onsite fuel storage
- Scrap yards
- Print works
- Paper manufacture
- Vehicle repair/manufacture/storage
- Gas works
- Timer products
- Landfill sites
- Chemical works
In the absence of a ground condition assessment (soil report) for a new or replacement distribution, where the site is presently employed as or has previously had activity in one of the above categories, your water authority is likely to ask you to lay your supply pipe in an approved barrier pipe material.
How can I find out for sure if the land is contaminated?
To determine if you have contaminated soil and will need to use barrier pipe, you'll need to get a floor condition assessment (soil report) carried out. We adhere to the WRAS Guidance Note 9-04-03 Issue 1, The Selection of Materials for Water Supply Pipes to be Laid in Contaminated Land, which you can get a replica of online. Then we might allow you to install MDPE if the levels of contaminants are below the limits given. However, if these limits are exceeded, then a barrier pipe will have to be installed. It's important to understand that a floor condition assessment (soil report) is used along with other procedures to determine the probability of contamination to your supply.