Under the Town Planning Ordinance, no person shall undertake or continue a development in a development permission area (DPA) unless the development was in existence before the relevant interim development permission area or development permission area plans were gazetted, or the development is permitted under the relevant statutory plan, or permission from the TPB has been obtained. Development not satisfying these criteria is an 'unauthorised development' (UD) subject to enforcement and prosecution action. Currently, about 19 764 hectares of rural land has been designated as development permission areas.

The Planning Authority may serve statutory notices on the respective landowners, occupiers and/or responsible persons, requiring them to discontinue a UD by a specified date or to reinstate the land. Non-compliance with a notice is a statutory offence.

The amended Town Planning Ordinance helps to improve the efficiency and effectiveness of planning enforcement in the rural New Territories. For instance, the new power of entry and investigation — which excludes domestic properties — makes it easier for the Planning Authority to collect evidence about alleged UD, in particular, the identity of the occupier.

In addition, an enforcement notice requires that UD must be discontinued within a specified period. The submission of a planning application is no longer accepted as a reasonable step towards complying with the enforcement notice.

In 2005, 275 new UDs were detected in the rural areas. Most were related to uses such as open storage of vehicles, containers and construction machinery/materials, workshops, and container vehicle trailer parks. The Director of Planning issued 1 510 warning letters for 296 cases, 1 284 enforcement notices for 195 cases, 161 reinstatement notices for 15 cases and 844 compliance notices for 168 cases. About 45 per cent of the enforcement notices were issued under the amended Town Planning Ordinance. As for prosecution, 61 defendants in 24 cases were convicted. The average fine imposed was $20,784 with a range of $5,000 to $333,000. During the year, enforcement action resulted in the discontinuation of 236 UDs covering 50 hectares of land, and regularisation of another 153 UDs covering 56 hectares of land through the planning application system.