SEVEN months after being damaged in the March floods, Browns Creek pumps are back in business.
The re-installation of the second pump at the end of October signalled the end of an arduous and expensive refurbishment, as one pump was left completely out of action and the other only partially operational due to debris damaging the pump's impellers.
In June Lismore City Council was forced to call on Fire and Rescue NSW to transport a pump up from Sydney during the minor flooding over the long-weekend.
The council's assets manager Scott Turner said it had been a big job, bigger in fact than most people would realise.
"The damage to the pumps was caused by debris being washed into intakes which caused vibration and damage to the impeller and pump blades," he said.
"Because the intake is low down under the water and the motor out of the water, there's a long shaft connecting the motor to the impeller and this is how the damage occurs."
The pumps were repaired in Brisbane as there were no local firms able to undertake the work.
"Each Browns Creek pump is 12 metres long, weighs around seven tonnes and can extract more than 10 million litres of flood-water per hour - which is the equivalent of around four Olympic-sized swimming pools," Mr Turner said.
"While there are some big numbers there, to put this into context, even with both pumps going flat out, it only handles 5-8ml per hour of rain in the basin."
Mr Turner explained the basin includes the Lismore CBD as well as the area around Ballina Rd heading up the hill towards Goonellabah and parts of East Lismore which drain off towards the golf course.
He said this can add up to a lot of water for the pumps to process.
"There were times in March we were getting 30ml, 40ml and 50 ml an hour," he said.
"It's been a two-stage process, rather than leave us without any (pumps). They were repaired and refurnished separately - the first one was put in place in September and the second one was put place last weekend."
Now the pumps have been reinstalled, Mr Turner said the next step was to work on methods to prevent the same damage happening again.
"So we are all back and fully operational and it's great we have them there and they serve a purpose, but we need to understand they can't solve everything," he said.
"So we have some other measures to protect the pumps, such as looking at more cages to collect debris, but it's a balancing act," he said.
"The more cages we use the less water gets through."