Page - 1342 - in Book of Full Papers - Symposium Hydro Engineering

This includes the completion of an application form accompanied by a construction completion report and associated as-built drawings, an operation and maintenance manual, emergency preparedness plan and an affidavit from the owner stating that all residential areas and buildings in the dam basin have been vacated. With regard to dam safety evaluations, the involvement of an APP and/or supporting professional team are similar to the other tasks (Category 2 dams only require an APP while Category 3 dams require an APP and supporting professional team). Depending on the category and the hazard potential, dam safety evaluations are required at intervals between 5 and 10 years (5 years for Category 3 dams and longer intervals for Category 2 dams). The dam safety legislation and regulations clearly set out the steps required to satisfy dam safety practice, but within the legislation or regulations there are no specific norms or standards prescribed. The APP has the responsibility to determine appropriate standards for a particular dam and the legislation provides for a review of such standards by the DSO. The appropriate norms are considered to be current acceptable dam engineering practice for site-specific conditions. This is significantly different to a number of other countries in the world where specific norms and standards are applicable. There are, however, a number of guidelines available for use in South Africa including these on Dam Break Floods [9], Safety in Relation to Floods [10] and Freeboard for Dams [11]. Again, it is important to note that the legislation is as such that the owner/s of a dam is at all times responsible for the safety of their dam – South Africa’s common law responsibility is applicable in addition to the dam safety responsibility. Included is the responsibility for the implementation of the recommendations of the dam safety evaluations by the owner. The DSO may instruct the owner to implement the recommendations. Failure of the DSO to give such an instruction does however not take the responsibility away from the owner. 2.3. WATER USE AND ENVIRONMENTAL LEGISLATION In addition to the dam safety requirements of the National Water Act of 1998 [8], a dam owner is also required to satisfy the water use requirements of the act by applying for a water use licence when wanting to construct any new dam or increase the storage capacity of an existing dam (Section 21 of the Act). No construction work may be carried out before a water use licence or written authorization has been obtained from the DWS. For so called “dirty water” dams (or dams for water containing waste), a dam owner must also comply with the Regulations on the “Use of Water for Mining and related Activities aimed at the protection of Water Resources” promulgated in 1999 [12]. A dam owner must also satisfy the provisions of the National Environmental Management Act and its accompanying regulations [13] with regards to activities which may have a detrimental effect on the environment (construction, enlargement, alteration, repair or decommissioning of a dam or storage of “dirty water” in most cases may be listed as such an activity). This normally requires an 1342