Horizons on standby for Moutoa floodgate operation

Horizons Regional Council will have an operation crew on standby at the Moutoa floodgates from midnight tonight.

Horizons controller Ged Shirley says current river level modelling shows that the Manawatū River could reach operating range around 7am tomorrow.
“The amount of actual rainfall received in the Manawatū catchment today has been less than anticipated so while we are still tracking for a gate operation, it’s not a given now,” he says.
“However, there is still some more rain expected overnight for the Tararua Ranges, and water from the upper reaches of the catchment to come down the system. At this stage we are expecting a peak of 5.3m at the Teachers’ College monitoring site in Palmerston North at 2.30am Wednesday.
“Levels at this site, combined with inflows between Palmerston North and Moutoa, is what informs our decision to open the floodgates to relieve pressure on the lower reaches of the Manawatū River. Having gate crews on standby at the gates means that we can easily operate if needed.”
Mr Shirley says that Horizons river management staff have managed to complete a temporary fix to the Ōkuku drain gates.
“This stops the Tokomaru River backing up that drain and potentially overtopping onto farmland. Contractors will be onsite to make sure the fix holds, and on the slim possibility that it doesn’t, we will open the Moutoa floodgates earlier to reduce river flows into the drain and Ōpiki basin.
“We will see the Manawatū River coming up over the next few hours and the spillway at Ōpiki will be operating soon, meaning State Highway 56 will be closed.”
Mr Shirley says Horizons’ emergency operations centre was activated this morning and staff will be monitoring the situation overnight.
“In general things are settling down across the region, however, while our river systems have responded well, they are all full. We have also had reports of surface flooding, erosion and trees down.
“We are monitoring the Ore Ore slip south of Raetihi which has seen State Highway 4 close one lane. While this hasn’t caused any issues to the Mangawhero River so far, we are keeping an eye on it in case a major slip results in a dam.
“Looking ahead to tomorrow we will also be considering if the flood barrier needs to be deployed to Foxton Beach to reduce the impact of storm surge in the afternoon. We will work with Horowhenua District Council on this if required.”
Up-to-date information on river heights and rainfall is available via Horizons 24-hour toll-free Waterline 0508 4 FLOOD and updates will also be posted to the Manawatū-Whanganui Civil Defence page
For weather forecasting information please see Metservice and for road closures, delays, and warnings please see NZTA