With all the very heavy rain falling recently in our area, heavy rain warnings and weather watches, we knew where all that rain fall and run off from the Tararua Ranges had ended up. So we took a drive along the Foxton-Shannon Road yesterday to check out the Moutoa Sluice Gates.
Moutoa Sluice Gates
The Moutoa Sluice Gates and floodway were completed in 1962, and are recognised as one of New Zealand’s outstanding engineering projects of the 20th century. They are at the centre of the vast and growing network of drains, stopbanks and floodgates that comprise the Lower Manawatu Scheme and protect the farms, orchards, market gardens and homes between the ranges and the sea.
The gates are able to divert water from the main river into a specially designed 10 km floodway that rejoins the river at Whirokino. The 10km Moutoa floodway bypasses 30 km of meandering channel as the Manawatu River makes its way to the sea at the Foxton estuary. The slow-flowing, meandering channel can easily flood and pour water over many hectares of valuable land. It is 600 m wide and is bounded on both sides by stopbanks 5.5 m high.
But it seems that the water has not yet reached the critical level, and the sluice gates remain firmly closed. Due to flooding, the gates are opened approximately once every 15 months, and local tenant farmers are given warning to move their stock off the flood plain paddocks, and lower their fences to prevent loss and damage.
Looking over the other side
Meanwhile, Horizons staff keep watch at the sluice gate site to monitor rising water levels and carefully manage the situation.
Man on duty