Less water in Lake Rotoiti in June
Friday, 31 May 2013 1:00 p.m.
Lake Rotoiti’s water level will be lowered by about 10cm from its usual operating levels during June, to encourage the flushing out of Ohau Channel.
Bay of Plenty Regional Council Principal Engineering Surveyor Graeme O’Rourke said the water level should remain lower than usual for anywhere from a few days to a month.
“If the weather forecast is fine the water level will remain low until the lake is replenished by winter rains,” Mr O’Rourke said.
“We will monitor the effect of the water reduction throughout the process, but we expect that it will expose some rocks and reefs and that may mean some boat sheds and launch ramps can’t be used.
“Regular users of the lake will most likely notice the changes, and we’re warning vessel operators to take extra care.”
Mr O’Rourke said the draw-down, or ‘flush’, through the Ōhau Channel is a condition of the resource consent for the Okere Gates.
“The hope is that the draw-down of Lake Rotoiti will increase water velocity in the Ōhau Channel, and flush out sediment. In time, the process may help to reduce the effects of flooding from high lake levels, particularly around Mourea,” he said.
“This is the second year we’ve done this, after a trial in 2011. Each year we’re collecting data and monitoring what happens and at the end of three years we’ll analyse the results.”
Regional Council works with local iwi, the Lake Rotoiti Community Association, and Fish and Game throughout the draw-down process.