The development of a low-pressure system off the New South Wales North Coast caused torrential rain on 2 March before dissipating as it entered Queensland. Heavy rainfall intensified over the following days, particularly in the Coffs Harbour and Port Macquarie regions.
River systems in the region were at capacity and tidal systems in correlation with the king tides also caused water levels to rise. The following river systems were affected; Richmond, Clarence, Bellinger, Nambucca, Macleay, Hastings, Manning, Paterson and Hunter.
The rising water exceeded levees in Kempsey and the traffic bridge at Kempsey peaked at a height of 6.9 metres. A reported 94 businesses suffered damage, with an estimated direct cost of $28,000 per business, while streets were closed to traffic. At the Mirriwina Gardens settlements, 50 kilometres north-west of Kempsey, 100 people were evacuated.
The Clarence River also threatened to exceed levees, causing precautionary evacuations of more than 1000 people, including 80 patients from the Grafton Hospital. The Grafton levee bank was able to hold the water within the river system, which finally peaked at 7.75 metres.
The effects of the flooding were wide spread and inundations and dislocation of services affected up to 28 local government areas. The Pacific Highway, the main route in many of these regions, was cut for several days. It was also reported that some rail services were suspended.
Further flood impact was reported at Yamba, which was isolated by flood waters, while sewerage infrastructure failure was reported at Gladstone and Smithtown, and at Ulmarra (population of 470), residents were ordered to evacuate. Bellingen, Thora, Kaland and Darkwood, South West Rocks, Hat Head, and Crescent Head were also isolated and required food and medical drops by helicopter.
The response units included; State Emergency Services (SES) with a contingent of 1300 volunteers from 83 units, Rural Fire Service (RFS), New South Wales Fire Brigade (NSWFB), Volunteer Rescue Association (VRA), Police, and Council workers. Additional supporting equipment used in the response included; ten heavy tankers, 12 flood boats, and 11 helicopters.
Estimated costs of damage to roads and bridges was $3 million, and water and sewerage infrastructure damage reported at $500,000.
The enormity of the recovery resulted in the Premier establishing a whole of Government task force to coordinate the operation. Brigadier Philip McNamara was appointed the regional coordinator for the recovery effort and was based at Coffs Harbour.
The Insurance Council of Australia estimated the 2001 damage at $25 million, with an 2011 estimated normalised cost of $45 million.