South Maui did not arrive at this moment overnight.
Kihei’s development history is not the result of a single bad decision. It is the accumulation of decades of assumptions, shortcuts, and missed planning. During the early statehood era, Kihei was widely viewed as dry, undesirable land. It was not taken seriously as a place that would ever see dense population growth.
Because of that, it was never given the level of coordinated planning that other regions received. There was no comprehensive effort to map and protect natural drainage systems, gulches, wetlands, seasonal streams, and other low-lying natural features as part of a larger environmental infrastructure. Instead, land was subdivided, sold, and built on piece by piece, without a unified vision for how water actually moves through South Maui.
Over time, development continued to layer on top of itself. What may have seemed acceptable at the scale of a single project became a serious regional problem when repeated over and over again. Natural systems were altered, redirected, buried, or erased entirely.
The result is what we live with today: a built environment sitting on top of what is, in reality, a floodplain, without the infrastructure needed to support it.
What we are seeing now is not new. It is the delayed consequence of long-standing, unregulated development in Kihei that never properly accounted for the natural behavior of water in South Maui.
Unregulated Development
Overdevelopment in the Kihei area was largely unregulated during the building booms of the 1970s and 1980s. At the time, the full extent of the area’s flooding hazards had not yet been formally calculated, and the long-term consequences of building across natural drainage systems were not fully recognized.
Only in more recent years have detailed flood studies revealed the true scale of the risk. Today, much of the area is subject to FEMA regulations, flood zone mapping, and flood insurance requirements. New developments are now required to meet tougher engineering and drainage standards than many older projects ever faced.
But that still leaves the larger question unanswered.
It is not just whether high-density projects can be built in a flood zone or wetland. The real question is whether they should be built there at all.
Development Increases Stormwater Production
Every new structure changes how water behaves.
Housing developments, roads, parking lots, driveways, and rooftops replace absorbent ground with hard surfaces. Instead of soaking into the earth, rainwater is forced to move faster, sheet farther, and collect in greater volumes.
This creates a compounding effect. Each new project adds more stormwater to a system that was never designed to handle it. In many lower parts of Kihei, drainage problems in South Maui are not theoretical. They are visible every time it rains.
The inadequacies of Kihei’s stormwater infrastructure are glaringly evident during even moderate storms. Flooding here is not rare. It is predictable.
Drainage Canals Covered Over
Historically, Kihei relied on natural drainage paths, open gulches, surface channels, and low areas that allowed water to move from mauka to makai. Many of those systems have since been altered, narrowed, diverted, buried, or built over.
In numerous housing and condo developments, natural drainage canals were moved underground and covered over. While that may have served short-term building goals, it created long-term maintenance and access problems.
Underground stormwater diversions are harder to inspect, harder to clear, and easier to neglect. When they become blocked or degraded, the failure may remain hidden until floodwaters back up into neighborhoods.
Several large developments on the mauka side of Kihei have underground stormwater diversions that are not readily accessible. These kinds of systems have contributed to a haphazard, disconnected network of ad hoc drainage measures rather than a coordinated, centrally managed system that can properly handle large runoff events.
Developments Diverting Their Stormwater
Over time, a troubling pattern emerged in parts of Kihei. Some developments managed water within their own boundaries, but not beyond them.
On the uphill side of Kihei, large projects created underground stormwater canals that were not connected to adequate downstream drainage systems. In practice, they simply moved water away from their own properties and discharged it onto vacant land or into areas that would continue carrying the burden downhill.
That means one property’s flood protection can become another neighborhood’s flood problem.
What protects a single development on paper may increase real-world risk for neighboring homes and communities below it. This is one of the core reasons why Kihei flooding must be understood as a connected regional issue, not just a parcel-by-parcel issue.
Natural Features Were Never Properly Protected
One of the deepest planning failures in South Maui is that natural infrastructure was never treated like infrastructure.
Gulches, wetlands, seasonal waterways, flood storage areas, and other natural features should have been recognized early on as essential parts of the landscape. These features were not vacant wasteland. They were part of the way the land functioned.
But Kihei was often planned and sold as though every parcel existed in isolation. The cumulative value of preserving open drainage paths, protecting low-lying areas, and respecting wetland functions was not built into the development model.
As a result, many natural features were degraded or lost altogether. That damage has come at a real cost: more runoff, less absorption, less flood storage, and more water forced into places where it does not belong.
Kihei Was Never Properly Recognized as the Floodplain It Really Is
For decades, Kihei was not fully understood or treated as the flood-prone landscape it truly is. That failure shaped everything that followed.
Too often, the dry appearance of South Maui created the illusion that water was a minor issue. But when major rains do come, the land reveals what it has always been: a place where water moves quickly, spreads widely, and depends on open natural pathways to reach the sea.
Without a serious regional plan to preserve those pathways, development steadily increased exposure to flood risk. The legacy of that short-sighted approach is now impossible to ignore.
Today, residents are left dealing with the consequences of decades of short-sighted development decisions that failed to account for the bigger hydrological reality of Kihei.
100-Year Flood Reality
Scientists estimate that a 100-year storm could funnel about 14,000 cubic feet per second of water into parts of Kihei. That is roughly two-thirds of the summertime flow of the Colorado River.
This is not nuisance flooding. It is a level of force capable of damaging homes, moving debris, undermining roads, and endangering lives.
That reality should fundamentally change how future projects are judged. The standard should not be whether a project can meet minimum paperwork requirements. The standard should be whether it makes an already stressed flood system worse.
A Difficult Truth
Former public works director David Goode said this about flooding in Kihei:
“The least costly thing might be to move people out. Has that ever been seriously considered? Well, there are instances of complete towns along the Missouri River that were removed.”
“That’s not gonna happen in Kihei, but there might be a few where it doesn’t make sense to have a structure right in the middle.”
“It really could be a lot worse. People need to plan for that, understand that, deal with it on their own level accordingly. And we’ll try to deal with it on the regional level.”
Read the full article here: Special Report: Kihei Underwater.
Where This Leaves Us
Kihei is now dealing with the legacy of decisions made decades ago, decisions that underestimated natural systems and overestimated our ability to control them.
We cannot undo the past. But we can stop repeating it.
Every new project should be evaluated not just in isolation, but as part of a larger, already stressed system. That includes how it affects downstream neighborhoods, how it alters runoff, how it impacts wetlands and drainage corridors, and whether it adds risk to a community that is already paying for earlier mistakes.
Because in Kihei, development is not just about buildings.
It is about water, and where it goes when there is nowhere left for it to go.