(1) If a permit for dam works, within the meaning of the Water Management Act 1999 , is in force under that Act, a permit or major project permit for those works is not required under this Act.(2) A water entity administering a water management plan or a water district is not required to hold a permit or major project permit under this Act for any activities which are (a) necessary for the operation, maintenance, repair, minor modification, upgrading or replacement of existing works managed or owned by that water entity and will not cause environmental nuisance, material environmental harm or serious environmental harm; or(b) required urgently to protect persons from injury or those works from damage so long as the activities will not cause serious environmental harm.(3) In this section environmental nuisance has the same meaning as in the Environmental Management and Pollution Control Act 1994 ;material environmental harm has the same meaning as in the Environmental Management and Pollution Control Act 1994 ;serious environmental harm has the same meaning as in the Environmental Management and Pollution Control Act 1994 ;water district has the same meaning as in the Water Management Act 1999 ;water entity has the same meaning as in the Water Management Act 1999 ;water management plan has the same meaning as in the Water Management Act 1999 .