Kula culvert blamed for storm damage

A culvert is just a pipe under a road. But when a storm hits, that little piece of infrastructure can decide whether water slips through quietly or blows out a hillside. That is basically the fight in Kula right now. Residents in this Upcountry Maui community say a culvert at a crossing was too small, got clogged with debris, and helped turn March’s Kona low storms into concentrated damage downslope. ### What actually happened in Kula? The immediate story is local and physical. People living near the crossing told Hawaiʻi Public Radio that huge volumes of water and debris came racing downslope during the recent storms, then piled up at the culvert intake instead of moving through cleanly. Once that opening choked, water overtopped the road and spilled into places it was never supposed to go — cutting channels, eroding land, and hitting nearby properties. (hawaiipublicradio.org) ### Why are residents blaming the culvert? Because flood damage often comes from the narrowest point in the system. A hillside can shed water across a broad area, but a culvert forces that flow through one opening. If the pipe is undersized for the storm, or if branches, rocks, and mud jam the entrance, the road starts acting like a temporary dam. Then the water looks for a new route — usually fast, dirty, and destructive. That is the core claim residents are making. (hawaiipublicradio.org) ### Why was this storm so hard on Maui? These were not ordinary showers. Hawaiʻi was hit by two consecutive Kona low systems beginning March 10 and again on March 19, with flooding, landslides, infrastructure damage, and evacuations across multiple islands. Governor Josh Green’s disaster request said losses from the first storm alone topped $400 million, with both events expected to exceed $1 billion statewide. Maui County was already in cleanup mode when more rain arrived. (hawaiipublicradio.org) ### Why does debris matter as much as water? Because culverts are designed for flow, but storms deliver whole landscapes. In a place like Kula, runoff can carry branches, sediment, rocks, and burned vegetation. The catch is that a culvert might be hydraulically big enough on paper and still fail in the real world if the inlet geometry grabs debris like a rake. Once the opening mats over, capacity drops hard and overtopping starts. (governor.hawaii.gov) ### Did earlier damage make this worse? Very likely. Kula has been living with layered risk for years — steep terrain, fragile roads, and the aftermath of the 2023 wildfire in parts of Upcountry. Burned or disturbed slopes can shed runoff and sediment differently than intact ground. Then add back-to-back extreme storms on already saturated land, and every weak point gets stressed harder. That is an inference, but it fits the broader pattern officials described statewide. (hawaiipublicradio.org) ### Why does one crossing matter so much? Because roads are where natural drainage and human systems collide. A bad culvert is like pinching a hose — pressure builds at the pinch, not evenly everywhere. When that pinch fails, the damage is concentrated. That helps explain why one crossing can produce outsized erosion and property loss even when the whole storm covers a much larger area. (governor.hawaii.gov) ### So what is the real lesson here? The lesson is not just “build bigger pipes.” Bigger can help, but only if the inlet, overflow path, maintenance, and debris behavior all make sense together. Storm resilience lives in the details — where water enters, where it escapes if blocked, and whether crews can keep the system clear before peak flow arrives. (hawaiipublicradio.org) ### Bottom line Kula’s culvert fight is really about how disasters become local. A statewide Kona low caused the rain, but one blocked chokepoint may have decided where the worst damage landed. That is why residents are focused on a single crossing — and why engineers usually are too. (hawaiipublicradio.org)