Options examined to upgrade boat shed weir
Community feedback on options to upgrade or replace the Avon River weir near the Antigua Boat Shed is being analysed and a recommendation will soon be made to the Hagley-Ferrymead Community Board.
Council engineer Paul Dickson says the rock weir in the river is not stable. "Rocks frequently tumble from the weir, making the water level upstream drop and boating more difficult," he says.
The Council asked for feedback on three options — adding more rocks, replacing it with a more formal concrete weir or creating a riffle of greywacke river stones. A concrete structure would be significantly more expensive than either of the other options. The Council got about 30 submissions.
Riffles are the broken-water sections seen in Canterbury gravel rivers. Because the Avon runs through flat terrain, it does not normally develop riffles, although a gentle form of riffle can be seen at Mill Island, Hereford Street.
"Other options have been considered but were discounted because they wouldn't have been durable enough or were more expensive without being significantly better." 
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