Initially thought to have been caused by a flooded transformer, the blast was later found to have occurred in a basement room used to store a lawnmower, fertiliser and fuel.
No one was hurt but one bystander said surprised firefighters and volunteers filling sandbags just metres away would have "needed to change their trousers".
Marsden Road was closed to traffic at high tide on Saturday morning and again from 6pm to 10am on Sunday. Contractors brought in rocks to shore up the seawall where the road, part of State Highway 11, was being undermined while Northland Civil Defence organised bags, labour and tonnes of sand to protect waterfront businesses.
One yacht was dashed to pieces on rocks, while a small launch was smashed when it was driven into a culvert next to the Salt Air helicopter pad. All that could be seen of another ill-fated boat was its bow poking above the water off Kings Beach.
Paths and gardens in Horotutu, a community-built park, were damaged and a large sign on Williams Rd had to be secured with cables after it threatened to fall on the busy shopping street.
The only business still closed yesterday was 35 Degrees South, which was expected to reopen by the end of the week.
It was the first real test of Paihia's new fire station and emergency command centre. The brigade had five call-outs between 7.40am and 4.50pm on Saturday, mostly for pumping out flooded basements, but remained on standby well into the night.
The volunteers were roused again at 4.30am on Sunday when wind brought a large flame tree down onto Puketona Rd, blocking both lanes near Bay of Islands Holiday Park.
Kaitaia, Mangonui, Kerikeri, Kaikohe brigades had three call-outs each on Saturday. Mangonui's volunteers were kept busy saving boats dragging their anchors or being driven on to rocks.
The Fire Service brought in five Auckland crews on Friday night to back up the weary Far North volunteers.
Power was cut to more than 2500 households in Pukenui, Kaitaia, Kaikohe, Taipa, Kawakawa, Okaihau and Kerikeri. Fifty Top Energy staff managed to restore power to the last 50 households by Sunday night.
The strongest wind gust, 120km/h, was recorded at Cape Reinga. The heaviest rain in the Far North fell at Wiroa Rd (86.5mm to 4pm on Saturday), followed by Kaeo (80.5mm) and Kaikohe (79.8mm). South Kaitaia got just 16mm while drought-hit North Hokianga recorded a mere 13.5mm.