Household Hazardous Waste Water Bills Department Title will go here. Since 1949, all pipe 750 mm diameter and larger has been laid in steel, lined with cement mortar and encased in concrete with all joints welded. Mains laid in tunnels are placed inside a grouted liner plate and the space between the liner plate and the steel main is filled with concrete. Except under special circumstances, in crossing sewers or under railway tracks, water mains are laid about 1.5 metres deep, just below the frost line, and hence follow ground contours. Mains are usually located in public streets both for ease of installation and quick access for maintenance.
Water mains have several appurtenances, located in chambers, which require preventive maintenance.
A chamber is an underground room or vault accessible from street level by means of covered surface maintenance hole openings. In the past, chambers were usually constructed of brick masonry or reinforced concrete. Currently, we are using circular precast concrete sections in most cases. These are used to isolate sections of the main as required for operation or maintenance. Branches are the connections through which water is supplied to the community areas.