Drainage

A drainage system which keeps foul water separate from surface water is called

• combined system

• separate system

• partially separate system

A drainage system which carries both foul and surface water in the same pipe is called

• combined system

• separate system

• partially separate system

A soakaway is used to dispose of

• rainwater

• foul water

• both foul rainwater

A disadvantage of a combined system is that

• it is an easier layout

• there is a needless cost to treat surface water

• it will never overflow

An inspection chamber allows access

• by allowing someone to enter it and get to drain level

• when working from the ground level only

An advantage of a separate system is that

• both foul and surface water are treated

• only foul water is treated

• only surface water is treated

An advantage of a combined sewer is that

• the sewer is flushed clean during heavy rainfall

• the sewer may overflow when there is heavy rainfall

• The sewer will never overflow

a manhole allows access to the drain

• by allowing someone to enter it and get to drain level

• when working from the ground level only

On a below ground combined system a gully is needed when connecting rainwater down pipes to

• allow for easier connection to the drain

• to stop smells passing from the drain

• there is no need for a gully

The type of ground suitable for a soakaway would be

• stiff clay

• loose sandy soil