Who uses the most water in Lahaina A new report says non-owner-occupied homes – Hawaii Public Radio

Report on Water Resource Management in West Maui and Alignment with Sustainable Development Goals

Introduction

A report from the state Commission on Water Resource Management provides a detailed analysis of water consumption in Lahaina, West Maui, utilizing data compiled as of August 7, 2023. The findings offer critical insights for future water management strategies, directly addressing several United Nations Sustainable Development Goals (SDGs), including SDG 6 (Clean Water and Sanitation), SDG 11 (Sustainable Cities and Communities), SDG 12 (Responsible Consumption and Production), and SDG 13 (Climate Action).

Analysis of Water Consumption Patterns

Key Water User Demographics

The report identifies the largest water consumers in West Maui, highlighting patterns that are crucial for achieving SDG 12 by promoting resource efficiency.

• Single-Family Dwellings: The largest collective user group, consuming approximately 5.5 million gallons per day (MGD).
• Hotels: The second-largest user group, consuming approximately 3.5 MGD.

Residential Water Use Disparities and SDG 12

A detailed examination of the 3,500 single-family home meters reveals significant disparities in consumption, underscoring the need for targeted conservation efforts to foster responsible consumption patterns.

• Over 50% of homes used less than 500 gallons per day, below the county standard.
• 358 meters, representing a small fraction of homes, consumed 2,000 gallons or more per day.
• Non-owner-occupied homes demonstrated a mean daily water use approximately double that of owner-occupied homes, indicating a significant variance in consumption behavior linked to residency status.

Commercial Sector Water Use and Infrastructure Challenges

The hospitality sector’s water usage presents challenges and opportunities related to SDG 6 and SDG 11, particularly concerning water quality and sustainable infrastructure.

1. Dependence on Potable Water: Many hotels in Lahaina utilize potable water for all purposes, including irrigation, due to a lack of infrastructure for non-potable or recycled water.
2. Infrastructure Gaps: The report notes that while areas like Kapalua and Kāʻanapali have access to non-potable water systems, expanding this infrastructure is essential for sustainable water management across West Maui.
3. Call for Innovation: Officials urge hotel operators to explore alternative water sources until infrastructure for recycled water becomes more widely available, promoting resilience and sustainability.

Water Scarcity and Environmental Stress: A Challenge to SDG 6 and SDG 13

Indicators of Acute Water Stress

The report paints a dire picture of the region’s water security, directly impacting the targets of SDG 6 (water availability) and SDG 13 (climate resilience).

• Prolonged Drought: West Maui has experienced significantly below-normal rainfall over the last five years, preventing the replenishment of groundwater reserves.
• Aquifer Degradation: Rising chloride levels in groundwater wells indicate increasing salinity, a sign of severe stress on freshwater resources.
• Impact on Freshwater Ecosystems: Stream flows across Hawaiʻi have reached their lowest recorded levels in over a century, threatening ecosystems and aligning with concerns under SDG 15 (Life on Land).
• Widespread Drought Conditions: As of late 2025, over 99% of lands in Hawaiʻi are experiencing abnormally dry to extreme drought conditions, highlighting the state’s vulnerability to climate change.

Recommendations for Sustainable Water Management

Promoting Water Conservation and Efficiency (SDG 6 & SDG 12)

The Commission emphasizes conservation as a critical, immediate strategy to mitigate water shortages and promote responsible consumption.

• A potential water savings of nearly 2 million gallons per day could be achieved in Lahaina if high-consumption single-family units reduced their daily use to 1,000 gallons.
• This measure highlights the significant impact that behavioral change and responsible consumption can have on preserving vital water resources.

Future Policy and Planning

The Commission is leveraging the report’s findings to develop a comprehensive, long-term water shortage plan that aligns with sustainable development principles.

• The objective is to establish consistent and equitable water use restrictions across both public and private water systems.
• This forward-looking approach aims to build community resilience and ensure the sustainable management of water resources for the future, directly supporting the goals of SDG 6 and SDG 11.

Analysis of Sustainable Development Goals in the Article

1. Which SDGs are addressed or connected to the issues highlighted in the article?

1. SDG 6: Clean Water and Sanitation

   • The article’s primary focus is on water resource management, consumption patterns, water scarcity, and the quality of groundwater in Lahaina, Maui. It directly addresses the challenges of ensuring the availability and sustainable management of water.

2. SDG 11: Sustainable Cities and Communities

   • The report analyzes water usage within a specific community, highlighting disparities between different types of housing (single-family homes, owner-occupied vs. non-owner-occupied) and commercial entities (hotels). It also touches upon infrastructure issues, such as the lack of non-potable water systems for irrigation, which are crucial for sustainable community resource management.

3. SDG 12: Responsible Consumption and Production

   • The article details patterns of water consumption, noting that some homes use “way more” than the standard amount. The call by Ciara Kahahane for residents and hotels to “cut back” on water use is a direct appeal for more responsible consumption to ensure the sustainable management of a finite natural resource.

4. SDG 13: Climate Action

   • The water shortages are explicitly linked to climate-related phenomena. The article states, “Rainfall in West Maui has been significantly below normal over the last five years,” and warns, “we have to prepare for the current pattern of drought in West Maui to continue.” This highlights the need to build resilience and adapt to the impacts of climate change.

5. SDG 15: Life on Land

   • The article reports that “Stream flows statewide registered some of their lowest recorded levels over the last few months, with many of them hitting their lowest point in more than 100 years on record.” This severe reduction in stream flow directly impacts freshwater ecosystems, which is a core concern of SDG 15.

2. What specific targets under those SDGs can be identified based on the article’s content?

1. SDG 6: Clean Water and Sanitation

   • Target 6.3: By 2030, improve water quality by reducing pollution… The article points to a decline in water quality, stating that the “level of chlorides in groundwater wells is rising,” which “means that the aquifer is becoming saltier, which is a bad sign for the availability of water.”
   • Target 6.4: By 2030, substantially increase water-use efficiency across all sectors and ensure sustainable withdrawals and supply of freshwater to address water scarcity. The entire article revolves around this target, analyzing water usage data (e.g., “5.5 million gallons per day” by homes) and advocating for conservation to address “severe water shortages.”
   • Target 6.5: By 2030, implement integrated water resources management at all levels. The article describes the work of the “state Commission on Water Resource Management” and its report, which aims to “help guide future water management decisions” and develop a “longer-term water shortage plan.”

2. SDG 11: Sustainable Cities and Communities

   • Target 11.5: By 2030, significantly reduce the number of… people affected… by disasters, including water-related disasters… The article discusses the “drought-plagued West Maui” and the development of a “water shortage plan” as a response to this ongoing disaster, aiming to mitigate its effects on the community.

3. SDG 12: Responsible Consumption and Production

   • Target 12.2: By 2030, achieve the sustainable management and efficient use of natural resources. The analysis of excessive water use by certain homes (“358 single-family dwelling meters used 2,000 gallons of water or more each day”) and the call for conservation directly address the need for more efficient and sustainable use of water resources.

4. SDG 13: Climate Action

   • Target 13.1: Strengthen resilience and adaptive capacity to climate-related hazards and natural disasters in all countries. The article’s statement that “we have to prepare for the current pattern of drought in West Maui to continue” is a direct call for building adaptive capacity to a persistent climate-related hazard.

5. SDG 15: Life on Land

   • Target 15.1: By 2030, ensure the conservation, restoration and sustainable use of terrestrial and inland freshwater ecosystems and their services. The mention of stream flows hitting a “lowest point in more than 100 years” signifies a direct threat to inland freshwater ecosystems, making their conservation and sustainable management critical.

3. Are there any indicators mentioned or implied in the article that can be used to measure progress towards the identified targets?

1. Indicators for SDG 6

   • Indicator for Target 6.4 (Water-use efficiency): The article provides specific quantitative data on water consumption that can serve as baseline indicators. These include:
     • Total daily water use by sector: “Single-family dwelling… at approximately 5.5 million gallons per day, with hotels coming in second at about 3.5 million.”
     • Per-unit consumption: “More than half of these homes used less than 500 gallons per day,” while “358 single-family dwelling meters used 2,000 gallons of water or more each day.”
     • Comparison of consumption patterns: “mean daily water use of non-owner-occupied, single-family home meters was approximately double that of owner-occupied homes.”
   • Indicator for Target 6.4 (Level of water stress): The article implies a high level of water stress through qualitative and quantitative descriptions:
     • “severe water shortages across the island”
     • “Rainfall in West Maui has been significantly below normal over the last five years”
     • “groundwater resources are becoming stressed”
   • Indicator for Target 6.3 (Water quality): A direct indicator of water quality is mentioned: “the level of chlorides in groundwater wells is rising.” This measurement can be tracked over time to assess the health of the aquifer.

2. Indicators for SDG 13 & 15

   • Indicator for Target 13.1 & 15.1 (Climate hazards and ecosystem health): The article provides clear indicators of environmental stress linked to climate patterns and ecosystem health:
     • Drought conditions: “more than 99% of Hawaiʻi’s lands are at or above abnormally dry conditions, and a growing percentage of those lands are in extreme drought.”
     • Health of freshwater ecosystems: “Stream flows statewide registered some of their lowest recorded levels over the last few months, with many of them hitting their lowest point in more than 100 years on record.”

4. Summary Table of SDGs, Targets, and Indicators

Source: hawaiipublicradio.org