In this Part—
"banks" means banks, walls or embankments adjoining or confining, or constructed for the purposes of or in connection with, any channel or sea front, and includes all land and water between the bank and low-watermark;
"drainage" includes—
"flood defence" means the drainage of land and the provision of flood warning systems;
"main river" (subject to section 137(4) below) means a watercourse shown as such on the main river map for England or the main river map for Wales and includes any structure or appliance for controlling or regulating the flow of water into, in or out of the channel which—
If any question arises under this Part—
the question shall be referred to one of the Ministers for decision or, if either of the parties so requires, to arbitration.
Where any question is required under subsection (2) above to be referred to arbitration it shall be referred to the arbitration of a single arbitrator appointed—
Nothing in this Part shall affect the powers exercisable by the appropriate agency under any local Act, as they existed immediately before the coming into force of this Act.