Enclosure 4 - Schedule 4a

                                                 Design, construction and safety – retaining walls, revetments and seawalls
 19.1 Prescribed tidal work that is a retaining     The design and construction of the retaining wall, revetment or   Not applicable
 wall, revetment or seawall, is designed and        seawall is consistent with the following standards—
 constructed in a way to ensure it is able to       (a) subject to paragraph (b), a retaining wall, revetment or
 support its intended loads, having regard to its   seawall is able to support at least a distributed live
 relevant loading matters.                          load of 3.0kPa;
                                                    (b) if a relevant planning scheme standard is more stringent than
                                                    the standard mentioned in paragraph (a)—the relevant planning
                                                    scheme standard, to the extent it is more stringent than the
                                                    standard mentioned in paragraph (a).
 19.2 Prescribed tidal work that is a retaining     The design and construction of the retaining wall, revetment or   Not applicable
 wall, revetment or seawall, is designed and        seawall is consistent with the following
 constructed in a way to ensure it can              standards—
 withstand—                                         (a) subject to paragraph (c), a retaining wall, revetment or
 (a) any tendency of overturning or sliding; and    seawall has a factor of safety of no less than 1.5;
 (b) any other effects of waves or changes in       (b) subject to paragraph (c), a retaining wall, revetment or
 water levels on the retaining wall, revetment or seawall is able to withstand the effect of waves, or waves and
 seawall.                                           water levels, resulting from a storm or other natural event
                                                    of a magnitude that has a 2% or lower probability of occurring in
                                                    any calendar year;
                                                    (c) if a relevant planning scheme standard is more stringent than
                                                    the standard mentioned in paragraph (a) or (b)—the relevant
                                                    planning scheme standard, to the extent it is more stringent than
                                                    the standard mentioned in paragraph (a) or (b).
 19.3 Prescribed tidal work that is a retaining     The design and construction of the retaining wall, revetment or   Not applicable
 wall, revetment or seawall not founded upon        seawall is consistent with the following standards—
 rock, is designed and constructed to protect       (a) subject to paragraph (c), a retaining wall, revetment or
 the seaward side of retaining wall, revetment      seawall provides for a sub-layer or enough filter material to
 or seawall from erosion.                           ensure it is reasonably likely to remain in place for at least
                                                    50 years;
                                                    (b) subject to paragraph (c), the bottom edge of the base of a
                                                    retaining wall, revetment or seawall is reasonably likely to
                                                    prevent any adverse effects from potential erosion of the soil
                                                    under the retaining wall, revetment or seawall for at least 50
                                                    years;
                                                    (c) if a relevant planning scheme standard is more stringent than
                                                    the standard mentioned in paragraph (a) or (b)—the relevant
                                                    planning scheme standard, to the extent it is more stringent than
                                                    the standard mentioned in paragraph (a) or (b)




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Coastal Protection and Management Regulation 2003 – Schedule 4A – IDAS code for the development of prescribed tidal work