The AH4CA Headwall is a two part Pcc Headwall that allows water to discharge at a 45 Deg. angle, the Environment Agency’s preferred method when discharging into a watercourse. The AH4CA headwall fully meets the Environment Agency’s ‘Standard rules SR2015 No 27 – Constructing an outfall pipe of 300mm diameter through a headwall into a main river’ & Exempt flood risk activities: environmental permits section FRA12 ‘Outfall pipes less than 300mm diameter through a headwall’.
The AH4CA is available with a backwall height of 600mm and three different toe depths for Twin Wall or Clay Pipes up to & including 300mm ID. Having a separate toe makes it easier to handle and more importantly ensures the foundation around the toe and beneath the Headwall structure can be well compacted.
|AH4C RH Angled Headwall Range||Max Pipe Opening (I.D) Plastic/C'ware||Max Pipe Opening (I.D) PCC||A mm||B mm||Approx Weight (kg)|
|AH4CA RH No Toe||300||225||600||0||375||CAD & PDF||Details|
|AH4CA RH 450mm Toe||300||225||600||450||795||CAD & PDF||Details|
|AH4CA RH 700mm Toe||300||225||600||700||1030||CAD & PDF||Details|
|AH4CA RH 1000mm Toe||300||225||600||1000||1310||CAD & PDF||Details|
Althon Headwalls offer a cost effective alternative to in-situ structures for connecting pipework discharging into open water courses.
All drainage pipes discharging into open watercourses, such as swales, ditches, ponds and rivers, should be fitted with an appropriate Althon headwall.