Permatreat is a versatile linear treatment system that can provide source control and pollution treatment in a wide variety of locations and applications.

Permatreat functions as a combined run-off collection, silt and oil interceptor and treatment system. It is designed to be laid with zero gradient to prevent the development of lateral velocities, ‘stilling’ sheet run-off from each sub-catchment and encouraging silt deposition within each channel.


The treated stormwater outlets discharge from the side of the treatment device, having passed through the Permatreat weir and baffle arrangement, which separates oil and silt, preventing it from progressing further into the drainage system.


Permatreat Product Codes:

Permatreat-S: PVTS
Permatreat-EA: PVTEA
Permatreat-HD: PVTHD


Permatreat is used for stormwater collection, interception and treatment of associated pollutants. The system comprises of single or multiple interconnected channels appropriately located to collect surface water run-off from sub-catchments of either impervious or pervious pavements. Permatreat is suitable for use in a range of applications including residential, industrial estates, car parks and lorry parks.



Permatreat-S and Permatreat-EA are rated to C500 and Permatreat-HD is rated to D400 loading in accordance with BS EN 124:1994 when installed with concrete bed and haunch in accordance with site specific construction details.


Installation Standard
Permachannel must be installed on a load bearing concrete bed and haunch, in accordance with site specific construction details. Please see the Permatreat Installation Guide for further details.


Key Features & Benefits:

• Gravity separation of oils and silts at source

• Trapped effluent naturally treated by aerobic digestion

• Can enhance water quality and eliminate the need for end of line petrol/oil interceptors

• The system complies with the regulations of the treatment train criteria in a SuDS scheme as defined in PPG3

• 100% recyclable




Note: Permatreat-HD was previously known as Permachannel.

Images of Permatreat are for illustrative purposes only. Over time the grating will develop a naturally occurring iron oxide protective coating often referred to as a patina. The colour of the patina is typically a deep reddish-brown and dependent on local conditions might take a year to reach its final colour. During early stages of this process it is normal for the grating colour to appear rust-orange.

Literature & Technical info