Moutoa floodgate operation not required

Horizons Regional Council will not be opening the Moutoa floodgates after rainfall levels for the region drop off.

Horizons incident controller Kyle Russell says the region hasn’t seen the amount of rainfall forecasted by Metservice appear today in the Tararua District and Ruahine Ranges.
“This means that while the Manawatū River is quite full, it hasn’t quite got to critical level at Teachers’ College that triggers a gate opening,” he says.
“There is always a degree of uncertainty when it comes to weather systems, and we do our best to make decisions that impact others within reasonable timeframes. We appreciate the cooperation and understanding of spillway lease holders who may have removed stock and dropped fences in preparation for an operation.”
Mr Russell says this is the third time in the last few months that river levels have got close to operating range.
“The decision to open the floodgates is not one that can be made lightly as it has roll on effects for the river channel downstream of Moutoa,” he says.
“Some people possibly wonder why we don’t simply open the gates as a precaution when it’s so close to the trigger point. The answer to this is that when we do open the gates and divert floodwaters down the spillway, the flow of water left in the downstream channel slows down which sees sediment deposit in the channel.    
“Every time that happens the channel capacity reduces slightly, so as this accumulates over time there is less room to carry water down its true path to the sea. The more we can keep the river flowing at a decent speed within the main stem, the better for the channel to ensure it doesn’t end up as a narrow space full of sediment.”
Mr Russell says Horizons will continue to monitor river levels over the weekend, however, do not anticipate any issues.
Up-to-date information on river heights and rainfall is available via Horizons 24 hour toll-free Waterline 0508 4 FLOOD or via our website
Follow the Manawatū-Whanganui Civil Defence page for future events:
For weather forecasting information please see