121. Dredging allowances.

Allowances are available1 if a person carries on a qualifying trade and qualifying expenditure2 has been incurred on dredging3.

'Qualifying trade' means a trade4 or undertaking the whole or part of which consists of the maintenance or improvement of the navigation of a harbour, estuary or waterway or is a qualifying trade for purposes of industrial buildings allowances5.

'Dredging' does not include anything done otherwise than in the interests of navigation, but subject to that includes: