A walk through Kawainui Marsh Trail: Wetland of International importance

Kawainui Marsh in Kailua is largest extant wetland in state of Hawaii and encompasses about 800 acres of beautiful wetlands. “Kawai” means water and “Nui” means large or abundant and refers to what really is a flood control levee at the foot of the ever-majestic Ko’olau Mountain Range.

This marshland has a geological past dating back to 4000 years ago, significant natural history and cultural history dating back to nearly 1000 years ago.  It is situated in center of former Ko‘olau volcano, Kawainui  was an inland extension of waters of Kailua Bay.

Overtime it was replaced by sandbar and eventually with the arrival of Hawaiian settlers it was used as fish pond.  They also planted lo‘i kalo (taro fields)along the streams and around the edges of the pond. Eventually as western civilization invaded Hawaiian land, the taro fields were replaced by rice fields and cattle ranch. Today, Kawainui is a wahi pana (storied place of cultural importance) and a wildlife sanctuary for migratory and waterbirds.

In 2005, Kawainui-Hāmākua MarshComplex was recognized and designated a wetland of international importance by the Ramsar Convention based on both its natural and cultural values. The site is also eligible for the National Register of Historic Places as a significant cultural and archaeological resource.

Today, water flows in the marsh from streams from Maunawili and Kapa‘a Valleys, springs along the Kūkanono slope, rainfall, and run-off  and the levee helps to contain the water, preventing  its run-off. In fact, it’s earlier name was Kawai Nui Loko, or "the big freshwater pond."

Kawainui-Hāmākua is also home to Hawai‘i’s 4 endangered waterbirds: the Hawaiian stilt (aeʻo), the Hawaiian coot (ʻalae keʻokeʻo), the Hawaiian gallinule (ʻalaeʻula) and the Hawaiian duck (kōloa maoli).

It is also home to several native marsh plants, including the neke fern and ‘uki (sawgrass). Restoration seeks to remove invasive plants, open water areas, and improve habitat for the native flora and fauna.

Culturally it is site of terraced rock walls of former housesites and lo‘i kalo, grinding stones for finishing stone adzes, and 3 large heiau or Hawaiian temples(Ulupō, Pahukini, and Holomakani).

Hamakua Marsh is a smaller wetland historically connected to and immediately downstream of Kawainui Marsh, which also provides significant habitat for several of Hawaii's endemic and endangered waterbirds.

Today, the Kawai Nui Marsh Trail is 3 miles round trip scenic, paved trail in heart of Kailua, away from hustle and bustle of the town. It is not much of a hike, but an experience unlike any other nature walk. You experience the beauty of wetland, amid the backdrop of majestic and magnificent Ko’olau mountains, hearing the chirping and quacking of birds and water birds and soaking in the greenery of flora.

parking lot

Being paved and graveled, it is suitable for strollers and wheelchairs as well as hiking with small children. Many people come here for walking the dog too. Parking is free and easily available. 

There is a picnic table and open lawn at the start of the trail if you want to have a picnic lunch.

picnic table

The beginning of Kawai Nui Marsh Trail

The levee on the trail 

Majestic Ko'olau Mountains in the backdrop 

wild flowers 

wild flowers

Water Hyacinth 

The marsh 

Algae in the Marsh 

A panoramic view of the trail 

The other side of levee 

A bicycle rider  

Nature's cut work 

Nature's cut work 

Houses on other side of levee 

Nature's cut work 

Bicycle stand 

Over the years, Kailua community and other communities have invested thousands of man hours to restore the native wetlands.  Ho‘olaulima Iā Kawainui is a network of conservation, native Hawaiian, educational, and community organizations who came together in 2004 to assist with planning the future of the Kawainui-Hāmākua Marsh Complex. The organizations comprising Ho‘olaulima are working with the State and the community on the restoration, interpretation, and stewardship of the marsh complex and the many significant natural and cultural resources that comprise this complex. A list of member organizations of .  Ho‘olaulima Iā Kawainui and other information can be found on the flyer.

Ho‘olaulima Iā Kawainui has worked upon developing  interpretive opportunities of Kawainui and Hāmākua. This will help in connecting people by sharing messages and themes and creating awareness about the geological and cultural importance of marshlands. It will also help into preservation and protection of the marsh and its resources for future generations.

The interpretive opportunities are also looking to build a visitor center, lookout and viewing platforms along the trails and providing hands-on opportunities for kiekies to learn how the marsh and wetlands were created.

The work at Kawainui is never-ending. Kailua Neighborhood Board president Charles Prentiss wrote, “Wetlands worldwide are being lost to encroachment and development of this kind, and the best of intentions to build “green or sustainably” can only manage the degree of harm, not prevent it.”