Volume Two 21. Floodway Zone 21.3.10.4. Stockpiling must be in the locations identified, and only up to the maximum quantities specified, in the MDC Marlborough Rivers Gravel Extraction Strategy. 21.3.11. Planting vegetation for the purposes of edge and aquatic habitat protection or prevention of bank and stopbank erosion. 21.3.11.1. Crack willow must not be planted on any floodway, except for the Wairau River downstream of the Wye River confluence. 21.3.11.2. When vegetation is planted for the purposes of aquatic habitat protection, native plant species must be preferentially planted. 21.3.12. Removal or control of aquatic vegetation in a river by cutting with an excavator mounted bucket with tined blades. 21.3.12.1. Cutting must not be carried out more than once in any 12 month period on any river reach, except that the Lower Ōpaoa River may be cut up to four times per year. 21.3.12.2. The removal or control must not be carried out in a tidal reach between 1 February and 30 April in any year. 21.3.12.3. The excavator must not enter flowing water. 21.3.12.4. The cutting must not be carried out over more than 90% of the channel width by leaving an uncut strip on each side of the river. 21.3.12.5. Removed material must be retained on adjacent river banks for a period not less than 12 hours to provide opportunity for fish and animals to re-enter the river. 21.3.13. Removal or control of aquatic vegetation in a river by a floating weedcutter with reciprocating blades, or by hand held cutters (e.g. scythes). 21.3.13.1. Cutting by mechanical means must not be carried out more than once in any 12 month period on any river reach, except that the Lower Ōpaoa River may be cut up to four times per year. 21.3.13.2. The removal and control must not be carried out in a tidal reach between 1 February and 30 April in any year. 21.3.13.3. The cutting must not be carried out over more than 90% of the channel width by leaving an uncut strip on each side of the river. 21.3.14. Removal or control of terrestrial vegetation in a riverbed by mechanical or other physical means. 21.3.14.1. The cut or felled vegetation must be removed from a riverbed less than 3m in width. 21.3.14.2. Vegetation greater than 100mm in diameter must be removed from a riverbed wider than 3m. 21.3.14.3. Machinery must not be operated in flowing water. 21.3.14.4. Removal of trees overhanging or partially in the water must be by machinery operated on the river bank or mounted on a boat or barge. 21.3.14.5. An assessment of the benefits of retaining vegetation, including an analysis of the potential ecological benefits to instream values, must be made before making a decision to remove or control the vegetation. 21 – 7