Ola Waikīkī!
Ola In Hawaiian, means well-being, living, thriving, and healthy—but it also connotes salvation, healing, and survival.
This webpage is a resource for community members, planners, and policy makers to learn about water quality issues the Ala Wai Watershed. The University of Hawai’i Sea Grant College Program is kicking off work to actively improve the health of the Ala Wai Canal though community outreach and in-ground green stormwater infrastructure pilot projects.
This project is funded by a grant/cooperative agreement from the National Oceanic and Atmospheric Administration (NOAA), Project A/AS-56 which is sponsored by the University of Hawai’i Sea Grant College Program, School of Ocean and Earth Science and Technology (SOEST), under Institutional Grant No. NA23OAR4690519 from NOAA Office of Sea Grant, Department of Commerce. The views expressed herein are those of the author(s) and do not necessarily reflect the views of NOAA or any of its subagencies. UNIHI-SEAGRANT-4859.
Explore the sections below to learn more about our current efforts, and click here to go directly to our community survey.
The Ala Wai Watershed includes the Pālolo, Mānoa and Makīkī valleys and is home to 200,000 residents and 80,000 visitors on any given day. The watershed includes many cultural sites, initiatives, stories, and moʻolelo of place that hold extraordinary cultural value and significance. It is also home to the economic hubs of Waikīkī, UH Mānoa, and Mōʻiliʻili.
The watershed includes rich and diverse natural resources, such as forest, riparian, coastal and marine ecosystems, and public spaces, parks, and waterbodies that are heavily used for recreation by the community.
There are issues within the Ala Wai Watershed with both excessive water quantity (flooding) and quality (pollution). This project is focused on addressing water quality issues in the Ala Wai Canal, a man-made waterway in the lower portion of the watershed. Water quality is degraded when pollutants like sediment, chemicals, or harmful microorganisms contaminate a body of water.
Green stormwater infrastructure is a collection of design strategies that mimic nature to manage and treat stormwater. Traditional ‘gray’ infrastructure uses vast networks of street drains, pipes, ditches, and canals to convey stormwater away from urban areas. Green stormwater infrastructure encourages water to infiltrate into the ground, minimizing and slowing the flow of runoff, and removing contaminants. Honolulu has a traditional ‘gray’ stormwater network, but there is an increasing recognition of the potential ecologic, economic, social, and cultural value of green alternatives.
There are many synonyms for green solutions. This project broadly defines green stormwater infrastructure as being inclusive of:
- Green infrastructure: systems designed by humans to mimic natural functions and infiltrate water into the ground as close to where it falls as possible (ie, rain gardens, bioswales, water catchment systems)
- Nature-based Solutions: the protection, management, or restoration of natural or impacted ecosystems (ie, planting native trees, wetland and streambank restoration)
- Bio-cultural restoration: the restoration of ecosystems with deep connections to culture and place (ie, native food, lei, and medicinal gathering forests, expansion of lo’i kalo, fishpond restoration)
In this project, Hawaiʻi Sea Grant is working to:
- Identify hotspots, policies, and practices that contribute to pollution in the Ala Wai watershed
- Collect of robust community feedback on preferred mitigation options
- Invest in demonstration projects through the allocation of mini grants
- Create future management recommendations
- Develop and foster community practices for improved watershed resilience
Water moves from land to sea, mauka to makai. Water quality conditions in the coastal lowlands of the watershed have degraded as a result of upstream urbanization (the conversion of green space to impervious land area), ecosystem loss, and waterway channelization. The Ala Wai Watershed drains into the Ala Wai Canal, which is chronically polluted.
Natural resources face pressures from urban development, invasive species, and polluted stormwater runoff. The Ala Wai Canal in particular suffers from severe pollution, including sedimentation, bacteria, heavy metals, organic debris, and trash that are generated on both private and public properties throughout the watershed.
Hawai’i Sea Grant recognizes that communities hold the knowledge and understanding of their places. In order to support nature-based solutions to the watershed’s biggest challenges, Hawai’i Sea Grant is distributing competitive mini-grants to organizations who are interested in installing, maintaining, and educating the public about a nature-based solution/green-infrastructure project within the watershed.
Application coming late June 2024
To get more information when it becomes available, please email mlander@hawaii.edu & eversole@hawaii.edu
There are many organizations working within the watershed and across the state to improve water quality and conserve natural resources.
As of June 2024, residents of the Ala Wai Watershed can receive a free rainwater assessment with Hawaii Green Growth’s Follow the Drop Initiative. This assessment will assist with determining credit and rebate opportunities for the Department of Facility Maintenance Storm Water Utility O‘ahu. The Department of Land and Natural Resources is currently accepting state-wide applications for the Kaulunani Grant Program to increase tree canopy coverage. Helpful resources to apply include the Forestry Program’s Tree Canopy Viewer Hawaii, Oahu STEW Map, Plant Pono Hawaii.
The interactive map below created by Hawaii Green Growth highlights stellar organizations and ongoing projects in the Ala Wai Watershed:
Below is a list of reports, studies, and articles written on the watershed without affiliation with Hawai’i Sea Grant.
Pre-1900: Waikīkī is a vast marshland of about 2,000 acres. Expanses of wetland agriculture dominate the watershed, including the modern neighborhoods of Waikīkī, Maikiki, Mōʻiliʻili, and Mānoa.
Extensive wetland agriculture in marshlands. (Image: Bishop Museum Archives)
1901: The first hotel in Waikīkī, the Moana Hotel, opens
The Moana Hotel in 1920, 1 year prior to the Ala Wai Canal’s construction (Image: Bishop Museum Archives)
1921: Board of Health President Lucius Pinkham orders the construction of the Ala Wai Canal, which effectively drained Waikīkī of its wetlands which were host to loʻi kalo, loko ʻia, duck ponds, rice ponds, and their stewards
1928: Construction of the Ala Wai Canal is finished. The original plan was to have two outlets into the ocean, but only the west outlet is included
Original plan for the Ala Wai Canal included a second outlet to the ocean (Image: Star Advertiser)
1962: Flood Control Act of 1962 authorized and directed the U.S. Army to do surveys in Hawaiʻi with the goal of flood control
- Flood Control Act of 1962 – U.S. Legislature, 1962
1965: Ala Wai Canal reaches capacity, flooding Waikīkī and causing streams in Mānoa and Pālolo Valleys to record the highest peaks since 1921
Ala Wai Boulevard with flooded water from the Ala Wai Canal in 1965 (Image: Images of Old Hawaiʻi)
1967: Ala Wai Canal reaches capacity, flooding Waikīkī for the second time
1967 + 1978: The Ala Wai Canal is dredged
The canal in 1967. (Image: Honolulu Star-Bulletin)
1992: Hurricane Iniki hits Hawaiʻi, mainly affecting the island of Kauaʻi
Image of wave crashing in Waikīkī area during Hurricane Iniki (Image: CNN)
1999: The Ala Wai Flood Risk Management (FRM) project with the United States Army Corps of Engineers begins
2002: The Ala Wai Canal is dredged for a third time
Other resources:
- Ala Wai Canal Watershed Project: Mānoa Valley District Park Streambank Improvements – City and County of Honolulu, 2000
- Ala Wai Watershed Analysis – State of Hawaiʻi Department of Land and Natural Resources and the U.S. Army Corps of Engineers and completed by Oceanit, Townscape, Inc., and Eugene P. Dashiell, AICP., 2003
2004: Mānoa Stream floods
- Manoa Valley Flood Oct 30, 2004 – NOAA National Weather Service, 2004
The aftermath of Mānoa Stream flooding at the Woodlawn Bridge in 2004 (Image: National Weather Service)
2006: Mākiki Stream floods
- Makiki Stream Flood, March 2006 – NOAA National Weather Service, 2006
2013: Mākiki Stream is dredged
2014: Aloha+ Challenge (Hawaiʻiʻs locally and culturally appropriate framework for the United Nations Sustainable Development Goals) launched
- Ala Wai Watershed Collaboration: Feasibility Study – Ala Wai Watershed Collaboration, 2021
2015: Department of Land and Natural Resources releases reports on options for improving water quality within the Ala Wai Canal
- 2015 Final Conceptual Engineering Report – Mitsunaga & Associates, Inc. for State of Hawaiʻi Department of Land and Natural Resources, 2015
- Ala Wai Canal Flushing System & Ala Wai Golf Course Detention System – State of Hawaiʻi Department of Land and Natural Resources, 2015
2017: Act 125 requiring the replacement of all cesspools by 2050 is passed
- Cesspools in Hawaiʻi – State of Hawaiʻi, Department of Health
2017: Notable king tide event in Waikīkī
- Waikiki Could Get Highest Tides In More Than 100 Years This Weekend – Emily Cardinali for Civil Beat, 2017
Water crashes against concrete walkway near Fort DeRussy in Waikīkī in 2017 (Image: Civil Beat)
2018: Funding for Ala Wai Flood Risk Management project is approved
- Ala Wai Flood Risk Management Study – U.S. Department of Defense, 2017
2019: 100 year anniversary of building of the Ala Wai Canal
- Ala Wai Centennial – Sean Connelly, 2019
Students reflecting on Sean Connelly’s Ala Wai Centennial piece in 2019 (Image: Ala Wai Centennial )
2020: U.S. Army Corps of Engineers release Engineering Documentation Report for the Ala Wai Flood Risk Management project
- Ala Wai Flood Risk Management Project – United States Army Corps of Engineers, 2020
2023: U.S. Army Corps of Engineers indicate plan to release second version of the plan for the Ala Wai Flood Risk Management project
- Ala Wai Flood Risk Management Presentation/Update Ahead Of April 24, 2023 Meeting – US Army Corps of Engineers and C&C of Honolulu, 2023
- Army Corps Rolls Out Its New Ala Wai Flood Control Plan – Civil Beat, Marcel Honore, 2023
- Army Corps Still Won’t Restore Forests As Part Of Ala Wai Flood Control Project – Civil Beat, Marcel Honore, 2023
2023: Congressional Funds are allocated to this project for improving water quality within the Ala Wai Watershed
For more information, please email mlander@hawaii.edu & eversole@hawaii.edu or call (808) 956-3012.