4Section 7 of the said Act of 1937 (which enables a local authority to make agreements for the reception and disposal of trade effluents with the owners or occupiers of trade premises within the district of the authority) shall be construed as enabling—
(a)the Greater London Council to enter into such agreements with the owners or occupiers of trade premises outside their sewerage area;
(b)sewerage authorities outside that area to enter into such agreements with the owners or occupiers of trade premises within that area ;
(c)the Greater London Council and any interested body in whom is vested a sewer in the Council's sewerage area to enter jointly into such agreements with the owners or occupiers of trade premises whether within or outside that area.