More time and money is needed to replace two pump stations in Mosgiel which failed to move water fast enough to stop flooding.
Dunedin City Council 3 Waters group manager Tom Dyer, speaking at a Mosgiel-Taieri Community Board meeting last week, said a project to increase the capacity of pump stations in Reid Ave and Carlyle Rd was continuing.
The new stations would be able to discharge about three times more stormwater than in their current state, he said.
The project began after flooding in July last year.
“Progress hasn’t been quite as quick as we had hoped. However, things are still moving.”
The design concepts, costings and “steps it will take to build” the stations had been finalised, he said.
However, the work needed to “achieve the flow outcomes” from the stations “was more complex than first thought”.
“It means additional cost and additional time.”
The construction work of the station in Reid Ave was now scheduled to start in October or November this year and be finished in late 2019, he said.
Construction of the Carlyle Rd pump station was scheduled to start early next year and finish in mid-2020.
“The building of pump stations in summer is a lot less problematic than in a wet season,” Mr Dyer said.
The current pump stations would continue running while the replacements were built.
Three mobile units would be available to support the current pumps during a “significant” rain event.
Excavators would begin working on a swale in Reid Ave soon, Mr Dyer said.
“The swale has lost some of its depth and grandeur over time, so we will reinstate that.”
At a board meeting in February, Mr Dyer said the swale was “a significant source of floodwater that causes damage to both the wastewater network and houses around Gordon Rd and south towards Carlyle Rd”.
The cleaning of the swale would reduce the impact of flooding to the playground for children aged under 5 in Memorial Park.
“Flooding should be far less frequent than it is at the moment.”