Subject to the provisions of this section, a local authority shall make full compensation to any person who has sustained damage by reason of the exercise by the authority of any of their powers under this Act in relation to a matter as to which he has not himself been in default.
Any dispute arising under this section as to the fact of damage, or as to the amount of compensation, shall be determined by arbitration:
No person shall be entitled by virtue of this section to claim compensation . . . on the ground that he has sustained damage by reason of any action of a local authority in respect of which the authority are by this Act authorised to pay compensation if they think fit.
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