Uncovering the Potential of Honolulu’s Hidden Streams – Next City

This story was made possible by our members. Join today.

Uncovering the Potential of Honolulu’s Hidden Streams

Centuries after Native Hawaiians built a vast irrigation system, sustainability advocates are working to put them back into the urban landscape.

Story by Timothy A. Schuler

Photography by John Hook

Published on Aug 22, 2016

On a characteristically sunny day in January 2014, Race Randle and a team of architects walked from the Honolulu office of Howard Hughes Corporation to a parking lot near the center of the Ward Village, the real estate development company’s 60-acre master-planned community in Kakaako, close to downtown. Randle, a senior director of development at Howard Hughes, wasn’t sure what they were looking for, only that, according to a 1928 map of the area, a curious easement ran through the property, from Kapiolani Boulevard all the way to the shoreline.

“It was odd because Victoria Ward owns the property, and there was an easement in favor of Victoria Ward, which isn’t that common,” Randle says. After a few minutes of speculation, he says, “we just walked out there to see what the heck it was.”

When they reached the location marked on the map, they found what appeared to be a sidewalk, running between a Sports Authority and Marukai Market Place, a Japanese grocery. They followed the concrete path until they saw a manhole cover. Randle lifted it. About 3 feet below was water. Not stormwater or sewage, but a stream, clean and crystal clear, pocked by small fish, flowing south toward Kewalo Basin just a few hundred yards away.

The stream was an auwai (‘auwai in Hawaiian), an irrigation ditch dug by Native Hawaiians to divert water from Oahu’s many streams to lo’i, wetland taro patches. Once upon a time, the entirety of Hawaii’s coastal plains was covered in terraced plots of taro, a staple of the Hawaiian diet and a sacred plant throughout Polynesian culture. Auwai crisscrossed the landscape. Water flowed from one patch to the next before returning, filtered, to the fish and salt ponds below.

Today, there is little evidence of this complex irrigation network, especially in Honolulu, where, like in other American cities, even natural streams have been buried, channelized or diverted into manmade canals. The auwai that Howard Hughes discovered was likely buried in the 1920s, encapsulated in concrete and forgotten.

Now, the company is exploring ways to daylight the stream, which originates roughly half a mile inland. The vision is to make the restored waterway a central feature of a new public park. “We’re always looking for inspiration in history,” Randle says. “You couldn’t ask for better inspiration. The water is still flowing.”

A concrete path covers a buried auwai in Kakaako.

If all goes as planned, this fall Howard Hughes will select the team that will lead the next phase of Ward Village, including the design of the park. Restoring the stream will involve demolishing the existing culvert (a square trough about 4 feet in diameter) and rebuilding a natural ecosystem where for decades there’s been cement.

Rivers much larger than the Ward Village auwai have been daylit in cities across the world, from London to Los Angeles to Seoul to Yonkers, New York. But in Honolulu, where the majority of streams have been altered in some way, the restoration’s value exceeds the boundaries of any one river. It is a vital opportunity to improve the health of the island’s freshwater and saltwater resources, while also potentially protecting communities from flooding and sea level rise.

Honolulu is in the midst of a building boom. Howard Hughes alone plans to add 4,000 units by the time Ward Village is built out. As the city grows, so will the pressure grow on its systems and resources, creating even greater demand for things like green stormwater infrastructure and other more natural approaches to civil engineering, which despite being shown to increase the resilience of coastal communities like Honolulu during tropical storms, have been slow to gain mainstream adoption in Hawaii.

Ward Village is just one of several new developments reshaping Honolulu. Much of the activity has centered on Kakaako, a former industrial district full of low-slung metal buildings that lies roughly halfway between downtown Honolulu and Waikiki and abuts the waterfront. Much of the development has been criticized for its emphasis on luxury housing when the city faces an unprecedented homelessness crisis, but when it comes to the auwai and Howard Hughes’ proposal to restore it, many support the company’s vision.

Matt Gonser is an extension agent of the University of Hawaii’s Sea Grant College Program and a city planner by training. He says daylighting the long-buried stream would reconnect residents with Honolulu’s waterways, including its once ubiquitous auwai, and could demonstrate to property owners their attendant benefits. “Not only is this a water feature,” says Gonser, who also has a master’s degree in landscape architecture, “it’s an extended green corridor. That kind of continuous habitat is really important.”

The concerete at this site could be ripped up to make way for a public park centered around the daylit stream.

The significance of the auwai extends beyond utility. Native Hawaiians, like other indigenous peoples, traditionally have seen themselves as part of the natural world, inseparable from wind or wave. “In Hawaiian culture, everything is sacred, from the most minute creature to the most powerful wind,” says Edward Cashman Jr., the director of Ka Papa Lo‘i O Kānewai Cultural Garden, an outdoor education center that includes a field of traditional lo’i at the University of Hawaii at Manoa.

Water is no exception, and historically auwai were governed in such a way that all Hawaiians had enough water to survive. Recovery of the auwai would be seen as a symbolic gesture within the Native Hawaiian community, says Paulette Ka`anohi Kaleikini, a Native Hawaiian activist who has met regularly with Howard Hughes as one of the developer’s cultural descendants, a group of Native Hawaiians with ancestral ties to the area. “It’s a huge step,” she says, “not only for the land but also for our lāhui, for our people.”

Randle still remembers the gravity of the meeting at which the team shared the news of their discovery: “We discussed it with the cultural descendants, and the feedback that we received was, ‘You need to find a way to bring the water back to the people.’”

The Value of an Urban River

All around the United States, cities are rediscovering the value of their waterways. Once little more than dumping grounds for industrial waste, urban rivers from the Schuylkill in Philadelphia to the Willamette in Portland, Oregon, are increasingly seen as assets, places for recreation, economic development and habitat restoration. Even in New Orleans, a city traumatized by the catastrophic collapse of its aqueous defenses, there is a growing awareness that the future lies in working with water rather than against it. Along one portion of the mighty Mississippi, new corrosion-resistant-steel bridges vault the floodwall, stitching the city and the river back together.

Unlike older, more industrial metropolises, Honolulu never lost its connection to its primary waterfront. The city has nearly 13 miles of open, accessible shoreline. But Hawaii’s streams are another story. Many have suffered decades of neglect. According to a report by the state’s Commission on Water Resource Management, roughly 20 percent of Hawaii’s streams are lined, straightened or otherwise channelized. On Oahu, where most of the state’s population lives, the figure is closer to 100 percent.

The most visible example is the Ala Wai Canal, a 2-mile-long channel dredged in the 1920s to drain the wetlands that eventually became Waikiki. Where Makiki, Manoa and Palolo streams had once drained into a natural estuary, today they are diverted into a concrete-lined canal. Such engineered solutions ignore the ecological connection between the ocean and the island’s streams. “A lot of people think that the ocean stops at the beach. They don’t realize that the ocean comes all the way up here,” Cashman says the day we meet at Kānewai, gesturing to a still natural portion of Manoa Stream, a mile and a half inland of Waikiki Beach.

Fish like the Hawaiian freshwater goby that are found only in the 50th state and its surrounding waters spend a portion of their lives in the ocean but swim upstream to spawn, just like salmon. When a stream is channelized, Cashman says, “you change salinity, turbidity, temperature, everything. You just screw it all up. And what happens is, all that water washes into the ocean and just kills everything.” In Maunalua Bay, on Honolulu’s east side, coral death has been linked to an excess amount of nutrient-rich runoff, according to a 2009 study published in the journal Estuarine, Coastal and Shelf Science. In their conclusion, the study’s authors wrote that restoration of the bay will require “proper land use management in the surrounding catchment to address the issue of pollution and excess nutrients and fine sediment from land runoff.”

Cashman is attempting to manage his slice of university land the way ancient Hawaiians did. Kānewai is one of few places in Honolulu where you can see an auwai in action. Originally built in the 1400s, the irrigation channel was restored in 1980 by a group of UH students and faculty and a veteran taro farmer named Harry Mitchell. Today, the auwai diverts water from the main waterway several hundred feet upstream to more than a dozen lo’i. After, the water returns to the stream. Thousands of students of all ages visit Kānewai throughout the year, learning about Native Hawaiian culture and working in the taro patches, but as important as the plant is, Cashman spends an equal amount of time teaching visitors about the stream and the auwai. “The taro is the hook,” he says. “But to us, it’s always about the water.”

Just a few years ago, this portion of the He'eia Stream was overgrown and choked with sediment and leaf litter.

Of course, engineers and urban planners have long regarded water as a problem, or something to be ignored, says Timothy Beatley, the Teresa Heinz Professor of Sustainable Communities at the University of Virginia’s School of Architecture. In his 2014 book Blue Urbanism, Beatley argues that city planners need to develop an “urban ocean connection” and that “coastal planning cannot and should not be restricted to terrestrial and upland shorelines, but must extend into the ocean.”

Honolulu’s urban waterways demonstrate that the opposite is true too. Marine conservation cannot ignore the effects of urban development and other land-based activities. In Hawaii, the disconnect between land and sea can be traced back to contact with Europeans, Cashman says. “As soon as the white man came, you can see a shift in thinking, in doing, what was right and what was wrong.”

Tactical Restoration

That a developer like Howard Hughes has proposed restoring the auwai in Kakaako could be evidence that attitudes about the importance of Hawaii’s waterways are changing. But some are skeptical. Sean Connelly grew up on Oahu and is an architect and artist in residence at the Santa Fe Art Institute. Until recently, he taught at the Harvard University Graduate School of Design. He worries that Howard Hughes’ proposed stream restoration is not the result of a sea change within the development community, but is instead a bargaining chip. “Thinking hard about the function of these stream restorations is important because if [it’s] just gonna be to make this playground area for rich people look nice, then that ends up becoming a tool to fight opposition,” Connelly says. “It ends up becoming a tool for gentrification.”

Troubled by what he sees as the status quo in Hawaii, Connelly’s work at Harvard has concentrated on landscape ecology and real estate development. He has been vocal in his criticism of some of Hawaii’s developers. “The last time I dropped Howard Hughes’ [name] in an interview, and it made it into the paper, I got a call from Howard Hughes that day,” Connelly says. Which turned into an opportunity. Connelly was invited to Howard Hughes’ offices to discuss the buried auwai. He told them that the “first priority is the quality of the water and how that’s affecting the ocean” and explained that there are several places where other water sources drain into the stream, bringing risks of contamination along with them.

The auwai certainly has been good for business. Celebrated chef Peter Merriman, long known as a champion of sustainable agriculture throughout Hawaii, cited it as one of his reasons for choosing Ward Village as the location for his new restaurant. “The fact that they’re going to restore the auwai in the area and are really paying respect to it was very important to us,” he told Pacific Business News last year.

But Connelly questions whether or not a water feature whose primary use is aesthetic is the “highest and best use” of Hawaii’s waterways.

“Being an island, and being so isolated, maximizing our sources of surface freshwater for irrigation purposes is super important,” he says, explaining that when he first began conducting his research in 2010, irrigation accounted for 50 percent of all groundwater used in Hawaii. “It’s a huge strain on our aquifer,” he says, and an unnecessary one, when “we have all these streams coming down every several miles.” Right now, the water in those streams is shunted into the ocean as quickly as possible. Instead, it should be used for growing food, Connelly says, just like it was 500 years ago. There are good reasons for doing so: Oahu imports almost 90 percent of its food and at any given time has about a week’s worth of food on the island. If managed properly, these productive landscapes would also filter runoff, reducing the amount of pollutants entering Honolulu’s waterways and, ultimately, the ocean.

“You can think of stream restoration as a tactic, it’s not necessarily the end goal. It’s one component of a larger effort to actually reclaim the entire watershed as something of a technology that we use to produce the resources we need to live on an island.”

Over the years, Connelly has become something of a defender of Honolulu’s waterways. He’s given talks and tours of the city’s hidden streams, including the auwai in Ward Village, and his argument for a watershed-based planning framework, “Urbanism as Island Living,” was published in the second edition of the anthology The Value of Hawaii in 2014. Growing up, however, Connelly rarely interacted with streams, and knew nothing about the importance of the island’s watersheds. “All I knew about watersheds was that the stream near my house in Kaneohe was a tunnel that went to the sewage plant,” he wrote in The Value of Hawaii. “At my Filipino Grandma’s house in Kalihi, the stream was down the hill at the end of the street, but too dirty to swim in so I never went.”

In 2008, Connelly’s brother-in-law, Rick Barboza, began restoring the stream that runs alongside his native plant nursery in Kaneohe, Oahu’s second-largest city. Barboza and his team cleared the stream’s banks of bamboo and hau (Hibiscus tiliaceus) and replaced them with more beneficial native species. Along the north bank, they exhumed and rebuilt many of the lo’i that once existed there. “They were 700 to 750 years old,” he says. “But they were three, three-and-a-half feet below all this mud. So all this mud was runoff.”

Today, a half-mile of He’eia Stream has been restored to a more natural condition. More interesting yet is the project’s funding: Barboza received a grant from the coastal management zone program of the National Oceanic and Atmospheric Association. “It was actually a grant for the ocean,” he says. “But what we’re trying to do is say, in order to keep [that] healthy, we gotta maintain up here. They said, ‘Of course, makes perfect sense.’”

Watching He’eia’s transformation take place inspired Connelly to make streams a major part of his thesis project, which has grown into Hawaii Futures, a public research project and kind of manifesto. For Connelly, and many other Pacific Islanders, the recovery of Honolulu’s streams is part of a much more comprehensive vision. “You can think of stream restoration as a tactic, it’s not necessarily the end goal,” he says. “It’s one component of a larger effort to actually reclaim the entire watershed as something of a technology that we use to produce the resources we need to live on an island.”

The blueprints for that technology still exist. Sometime around 1000 A.D., Hawaiians developed a sophisticated land use system structured around ahupua’a, long, often thin parcels of land that stretched from mountains to sea. These divisions were social, political and economic, designed to ensure that each community had access to mountain resources like fruits and wild pig as well as lowland and ocean staples, like taro and fish. Auwai played a central role.

Unlike 20th century engineering, the system was “engineered to plug into the hydrology of the watershed, and designed to assist the natural flow of water, reinforcing the relationships between forests that attract and capture the rains, the streams and wetlands that filter it, and the shorelines that eventually receive it,” Connelly writes. “This system was so effective, it intensified the cultivation of food by 100 times the previous amount.”

“Over time,” Connelly continues, “this system became ingrained in the natural hydrology, and transformed the watershed itself into an advanced technology — a tool to intensify the production of food and other resources.”

He’eia is proof that the technology is still viable. The question is how to replicate its success in denser, urban areas. As a starting point, Connelly is advocating for the incremental acquisition of properties along Honolulu’s urban streams, to be maintained as continuous corridors capable of sustaining native fish and plant populations. Such an endeavor would take decades to complete, Connelly admits, as well as an enormous amount of money. How much money? Two billion dollars per ahupua’a, according to Connelly’s calculations, which he has performed for every single one in the state. “I’m kind of a nerd about it,” he says. “Every day I plug in new data if I can find it.”

If $2 billion sounds like a lot of money, it’s dwarfed by the price tags of other major infrastructure projects, Connelly says. Boston’s Big Dig, for instance, cost $24 billion. With the same amount of money, Honolulu could recover 12 of its 13 ahupua’a, an area that would stretch from Moanalua to Hawaii Kai.

In the meantime, Barboza says there are some urban waterways that could be restored right now. “I would love to do those areas that are channelized, like in downtown Honolulu,” he says. “They [have] a ton of sediment buildup along the margins that I think could be useful in either creating habitat or filtering out the water before it goes out into the ocean.” Change won’t happen overnight, Barboza says, but every little bit helps. “We live on an island. We need the fresh water. We need that water to go back in the ground, we need to feed the streams.”

A Beloved Toxic Soup

In Honolulu, no waterway is as complex — or its future as contested — as the Ala Wai Canal. As the defining boundary of Waikiki and the site of a proposed federal flood mitigation project, it has become ground zero in the debate about how to manage Hawaii’s streams.

The Ala Wai is simultaneously Hawaii’s most polluted waterway and also its most used. Despite being a toxic soup of deadly bacteria, heavy metals, occasional raw sewage and harmful amounts of phosphorus and nitrogen — the kinds of nutrients that kill coral reef — the canal reportedly has the single largest concentration of canoe clubs in the state, and runners and cyclists stream along its palm-lined promenade.

Nearly 200,000 people — 20 percent of the island’s population — live within the Ala Wai’s watershed. As the city has grown, so too has the volume of runoff the canal has needed to handle. As a result, flooding has become an increasing issue, and in 1998, the U.S. Army Corps of Engineers (USACE) began a feasibility study of flood mitigation measures, which was later expanded to include ecosystem restoration and water quality improvements.

But in 2013, objectives not directly related to flood mitigation, i.e., ecosystem restoration, were abandoned. “The Army Corps headquarters said, ‘Forget it, you’ve been working on this too long, figure out a flood mitigation project, get it done,’” says Sea Grant’s Matt Gonser. Now, proposed improvements include a series of detention basins throughout the watershed and floodwalls along either side of the canal. Cashman, who has been consulted by the USACE, is dismayed by a plan that relies so heavily on built infrastructure. He says if the Army Corps wants detention basins, they should build lo’i, which, as Barboza has demonstrated, have the ability to significantly slow runoff and filter out sediment.

The Ala Wai Canal is one of the city's most polluted waterways.

Cashman isn’t alone in his desire to go beyond mere flood mitigation. Last year, an alliance of government agencies, private interests, academic partners, and nonprofit and community organizations formed the Ala Wai Watershed Partnership with a mission of building support for a longer-term and more comprehensive response to the threats posed by the Ala Wai.

In September, the partnership plans to announce the Ala Wai Resilience Challenge, an international design competition inspired by Rebuild by Design and other resilience-focused competitions of its kind. Though details have yet to be released, Gonser says the goal is to leverage local and international design and planning expertise to develop an investment strategy and climate-resilient infrastructure plan for the entire watershed. It’s a markedly different approach from Barboza’s grassroots restoration, more ambitious in scope but accompanied by corresponding challenges. As is often the case with design competitions, there is no guarantee that a winning plan will be implemented. (This is also true of any USACE proposal, which must be reviewed by Congress before funds are appropriated.)

And yet there could be peripheral benefits, including increased communication between sectors and a heightened awareness among residents. “That’s the strength of some of these huge infrastructure ideas out of Rebuild,” says Gonser, who is a member of the partnership. “I don’t think we’ll ever have that scale of funding support, but just the engagement makes things more palatable. People are more supportive because not only are they learning about the benefits, but they’re even offering up the ideas themselves.”

“A Place Like No Other”

Compared to the Ala Wai Canal, the Ward Village auwai is little more than a trickle. And yet uncovering the stream has proven more challenging than Howard Hughes originally suspected. Among the many obstacles is the fact that the water could be shut off at any time. Although the auwai was originally spring fed, with the development of the Blaisdell Center concert hall in the 1960s, the spring was converted into a well and the water pumped up to the venue’s decorative ponds. Howard Hughes doesn’t own the well or the property around it, and Randle says there’s been talk that the area could be redeveloped in the near future. “[We] don’t always know if the water’s going to flow,” he says.

Water flows down the auwai at Kanewai. 

The city, however, which operates the Blaisdell Center, is supportive of the proposal to daylight the stream, Randle says, and some sort of negotiation may yet be worked out. In the meantime, Howard Hughes has engineers exploring the idea of a hybrid system, in which a backup source of water would be tied into the stream to ensure a steady flow of water. Alternatively, engineers could design a saltwater loop system, which would not rely on the current headwaters at all. Gonser says the company could also employ a dry stream design that could be allowed to flood. Right now, Randle says, everything is on the table.

The notion of incorporating more natural systems into urban design and infrastructure projects is catching on in Honolulu — in its RFP for improvements to the Kapalama Canal in Kalihi, the city specified that green infrastructure be part of the final design — but adoption has been slow, especially compared to cities like Philadelphia and Seattle. “We’re not at the bottom,” Gonser says. “We’re not in the Stone Age. But we’re certainly not on the forefront.” Part of the reason, he says, is that Hawaii has no analog. Its watersheds are short and steep, its soils unlike those on the mainland. “It’s all well and good if you identify some practice on the mainland,” he says, “but will it work here?” To share what knowledge does exist in Hawaii, Gonser organized a Green Stormwater Infrastructure Summit, a one-day symposium that took place in August.

Connelly agrees that there are limits to how much Hawaii can learn from other places. He says he’s often asked by people what the reclamation of the ahupua’a will look like in the 21st century. He tells them he doesn’t have the answer. “The answer is in the soil types, and in the rainfall,” he says. Native Hawaiians understood this. “They knew how to listen to Hawaii,” he says. Which is why Connelly plans to return to Oahu in the near future. He says his time at Harvard has confirmed for him what he’s suspected for a long time: Hawaii is a place like no other, and the knowledge that exists here can be found nowhere else.

Our features are made possible with generous support from The Ford Foundation.

Timothy A. Schuler writes about design, ecology, and the environment. He lives in Honolulu.