Occasionally situations occur where unusual circumstances surrounding a drainage connection exist.

These may not be immediately obvious at the outset but if the client is aware of them they should be pointed out.

Once started it is extremely difficult, costly and time consuming to change over construction methods.

In practice, with local authority requirements, it may well mean the closing up of an excavation and re-opening at a later date when resources can be brought to bear and the relevant permission sought from the local authority and sewerage authority.

    Such scenarios include, but are not limited to:-

        1.  'Running' ground materials e.g. running sand or ballast

        2.  Works below water table or adjacent to/in underground water courses

        3.  Pitch fibre or resin lined pipes types and sizes into which the connection executed

                e.g. 7" asbestos pipe

        4.  Traffic management requirements from the local authority e.g. tunnelling or restricted working

        5.  Sewer depths and locations