From removing sand from under the bathers' pavilion at North Wollongong Beach to filling potholes and clearing uprooted trees, more than 60 Wollongong City Council staff were on the job from 6.30am.

At the pavilion, council lifeguards used shovels to shift sand from underneath the refurbished building, while a backhoe attracted many onlookers as it helped clear the surrounds.

Equipment inside had been removed before the storm and large swells hit, a council spokeswoman said.

"While a large amount of sand, at times knee-depth, and seawater did make it into the beach-level parts of the pavilion, the building has been designed to withstand these extreme conditions. There are no reports of damage to the 2012 restorations," she said.

North Wollongong, Towradgi and Fairy Meadow beaches were closed on Thursday due to debris and overflow from nearby creeks and lagoons.

The car park at Austinmer Beach was also closed so a build-up of sand could be removed, while a street sweeper was put to work along footpaths at Flagstaff Hill.

Work to clear the aftermath of the intense east coast low is expected to continue for a number of days, with council's machinery too heavy to use on the waterlogged ground. The spokeswoman said jobs were being prioritised, including the route for Saturday's Anzac Day march.

"Some potholes have appeared on this route as a result of the rain and the crews are working to ensure these are fixed before the commemorations," she said.

Bureau of Meteorology senior meteorologist Sean Carson described the system that pelted the coast as "close to a one-in-10 year event".

"We're probably talking 48 hours [at Bellambi] of the winds gusting to 98km/h, not to mention the rain was just sideways the whole time and that's whipping up the seas as well," Mr Carson said.

"We can all take a bit of severe weather in short bursts but when you get it parked off the coast and cop it for 48 hours straight it makes for some pretty miserable times."

According to the Manly Hydraulics Laboratory which collects offshore wave data for the state government, readings from the Port Kembla wave buoy were inconsistent due to communication issues.

"I've actually seen a maximum wave there of 16.1 metres, which is massive but it's actually not out of question given the Sydney buoy recorded a 14.9 metres," Mr Carson said.

Late Thursday afternoon, the SES had received 400 calls for assistance in the Illawarra and 14,283 statewide since 8am Monday.

Coal was set to be hauled by train to Port Kembla again on Thursday night after the port's coal terminal reopened following this week's storms.

While the port itself was reopened at 5pm on Wednesday, road receivals of coal were stopped because of several electrical faults, Port Kembla Coal Terminal general manager Peter Green said.

Staff were now preparing to push coal back into the stockpiles after some "slumping" had been caused by days of heavy rain, and this would cause some delays to ship loading.

"Stockpile slumping has occurred for several stockpiles, some of which will need to be addressed prior to ship loading commencing," Mr Green said.

"A stockpile slump recovery plan is being executed in a safe and efficient manner.

"Pushing in of slumped material onto stockpiles will be necessary across the coming days.

"Additional time is scheduled across ship loading to accommodate."

The slumped coal would need to be given time to dry.

The harbour was closed by the harbourmaster about noon on Monday.

Ben Langford