A six-week dredging project got underway at Sullivan Lake this week, utilising specialised equipment sourced from Denmark.
Contractor ECL Group is using a unit mounted on a floating barge to pump silt dredged from the lake bottom to dewatering units on the lake shore, where the sediment is removed and clean water returned to the lake.
The dewatered silt will then be transported to a drying-out site at the Awatapu Lagoon Reserve, in preparation for landscaping use.
In a separate, week-long operation, a land-based long-reach digger is removing sediment from the upper (south-eastern) section of the lake. The material removed will be stockpiled on the lake edge for two-to-three days to dewater, and then transported to Awatapu.
The areas involved in the dredging operations will be temporarily closed to the public.
Whakatāne District Council Places and Open Spaces Manager Mike Houghton says the focus of the dredging operation is on improving water quality.
“Deepening the lake will mean it doesn’t warm up as much during the summer months, which should have positive effects in terms of dissolved oxygen and the potential for algal blooms, improving the environmental conditions for bird and aquatic life,” he explains. “We’ve been working closely with the Sullivan Lake Care Group, which has been strongly advocating for water quality improvement in recent years. The group’s efforts in beautifying and maintaining the Lake reserve are very much appreciated and it’s great to get the dredging programme underway, after a number of delays due to resource consent and seasonal factors.”