2024 East Sepik Earthquake
The river was already over the doorsills when the ground began to shake. For weeks the Sepik had been running high, pushing into villages built on stilts and flooding gardens that should still have been dry. At 6:22 on the morning of 24 March 2024, a magnitude 6.9 earthquake struck east-northeast of Ambunti, and the people of the lower Sepik - some wading through chest-deep water inside their own homes - found themselves in a disaster compounded. Wooden houses with thatched roofing do not hold up to severe shaking, and many did not hold up at all. In the village of Sotmeri, all 45 houses collapsed at once.
Two Disasters, One Morning
The U.S. Geological Survey recorded the epicentre north of Chambri Lake, a shallow hypocentre that delivered a maximum Modified Mercalli intensity of VII - very strong shaking. Tremors of intensity VI to VII were felt by an estimated 487,000 residents across East Sepik and Sandaun Provinces, reaching as far as Goroka in the Eastern Highlands. Five people were confirmed dead almost immediately, but East Sepik police commander Christopher Tamari warned the count would rise. Around a thousand homes were destroyed outright. The International Organization for Migration later estimated 10,000 people displaced and 400,000 affected, largely because the earthquake had landed on top of ongoing floods that had already displaced and weakened riverine communities.
Villages on the Water
Most houses along this stretch of the Sepik are built of timber and sago-palm thatch, raised on stilts against the river's seasonal swings. That architecture is a brilliant adaptation to flooding. It is not an adaptation to earthquakes. At Kamanibit village in Angoram District, 39 houses collapsed and were immediately swallowed by the floodwater beneath them. Eleven more collapsed in Jikinumbu, where a seven-year-old girl and her mother were killed. Seven houses fell in Yenjimangua, eight in Niaurange. Many residents could not flee - the water around them was already too deep to run through. A landslide in Yangoru-Saussia District buried gardens. In Maprik District, eight more died.
A Province in Two Crises
East Sepik declared a state of emergency on 25 March, and the provincial government released 200,000 kina in immediate relief, pledging five million more. Governor Allan Bird asked the U.S. embassy in Port Moresby for 5,000 water filters and buckets - clean drinking water being the first and most urgent casualty when floodwater overtops every well. Samaritan Aviation, USAID, IOM, and Vodafone moved in alongside local authorities. A civilian helicopter was deployed from Wewak, soon joined by a military helicopter. Eighty-six schools in Ambunti, Wosera-Gawi, and Angoram suspended classes indefinitely. On 29 March, Defence Minister Billy Joseph announced that Australia would send a C-27 Spartan aircraft loaded with aid, which landed in Wewak the following day.
The Cost Counted
On 30 and 31 March, Prime Minister James Marape visited East Sepik and the other districts devastated by the twinned disasters. He put the combined damage from the earthquake and the floods at 221 million kina - roughly 58.7 million U.S. dollars. The United States released 3.45 million kina in humanitarian aid. Students and faculty at the Papua New Guinea University of Technology in Lae ran a donation drive of their own. The numbers sound manageable until you visit a stilt house that is no longer standing, or a garden that has disappeared beneath silt. A month after the earthquake, remote villages were still waiting for supplies. The Sepik, Papua New Guinea's Amazon, can be cruel when it rises, and when the ground beneath it shifts as well, the arithmetic turns brutal.
Living on the Arc
This is not the first disaster for the lower Sepik and it will not be the last. In April 2023, a magnitude 7.1 earthquake southeast of the 2024 epicentre killed eight. In 2002, a 7.6 quake off the Sandaun coast - the largest to hit mainland Papua New Guinea since 1938 - damaged homes in Wewak, Aitape, and along the coast. Northern Papua New Guinea sits on the colliding edges of the Australian and Pacific plates, where the Huon-Finisterre island arc is still being shoved into the Australian continental margin. The Sepik people have lived here through all of it. They rebuild with the materials they have, on the land they know, and the river continues to rise and fall around them.
From the Air
The epicentre sits at roughly 4.139 degrees south, 143.159 degrees east, in the Sepik lowlands north of Chambri Lake and east-northeast of Ambunti. Wewak airport (AYWK / WWK) is the primary air gateway for East Sepik and was the staging point for relief helicopters and the Australian C-27 delivery. Vanimo (AYVN / VAI) serves Sandaun Province to the west. From cruising altitude the Sepik appears as a glinting, meandering ribbon of oxbow lakes and swamp channels flowing west to east toward the Bismarck Sea. Expect high humidity, afternoon convective buildups, and seasonal floods that visibly widen the river each wet season. The Sepik floodplain is strikingly flat - much of it barely above sea level even hundreds of kilometres inland.