South Maui Sand Dunes

The South Maui Sand Dunes are remnants of ancient coastal processes, primarily shaped by sea-level fluctuations during the Pleistocene epoch. These dunes were originally stabilized by native vegetation, which helped to maintain their natural balance and prevent excessive movement.

Issue: Interruption of Natural Dune Dynamics

The problem arises from human development, particularly in South Kihei, where roads, infrastructure, and urban expansion interfere with the dunes’ ability to move seasonally. Normally, these dunes would advance and retreat in response to wind patterns, ocean currents, and seasonal changes, playing a crucial role in coastal protection and sediment distribution.

However, with the construction of South Kihei Road, the natural movement of the dunes is obstructed. This leads to several consequences:

Loss of Natural Coastal Protection – The dunes act as a buffer against storm surges, high tides, and erosion. When they are restricted, coastal areas become more vulnerable to flooding and damage.
Increased Sand Drift in Unintended Areas – With no natural equilibrium, windblown sand can accumulate along roads, private properties, and unintended areas, requiring costly maintenance efforts.
Erosion of the Dunes – Without free movement, the dunes degrade over time, leading to permanent loss of coastal sand reserves.
Disruption of Littoral System – The littoral system, which includes the beach, dunes, and nearshore waters, depends on sediment transport to maintain a balanced ecosystem. Blocking the dunes disrupts this cycle.

Possible Solutions

Reintroducing Native Vegetation: Encouraging the growth of naupaka, pōhuehue (beach morning glory), and ‘aki‘aki grass can help stabilize shifting sands while allowing for some natural movement.
Managed Retreat or Adaptive Infrastructure: Modifying road designs, implementing dune walkovers, or even relocating sections of South Kihei Road could allow for more natural dune migration.
Sand Fencing & Restoration Projects: Creating sand fencing systems in critical areas could help mitigate unintended sand accumulation while allowing controlled movement.
Community & Policy Engagement: Encouraging local support for dune restoration projects and coastal resilience policies to protect these dynamic landscapes.