Issue 9.5: October/November 2006

On Golden Ponds

story by Rose Kahele
photos by Monte Costa

 
David Chai holds an oyster harvested
from Punawai pond, a two-and-a-half

acre, man-made pond on the grounds
of Hualalai Resort.

When David Chai was a sophomore at the University of Hawai‘i at Hilo, he fell into a saltwater pool and fell in love.

While walking along the rocky coastline near Kings’ Landing, just outside of town, Chai stepped into what he thought was a shallow, stagnant saltwater puddle. Instead, the water went up to his thigh, and he plunged into a world of tiny specialized shrimp, rare plants, strange algae and exotic bacteria.

Chai had fallen into an anchialine pond, one of Hawai‘i’s most threatened and mysterious ecosystems. These seemingly landlocked bodies of brackish water are found along the Islands’ coastal lava flows, connected to the ocean via subterranean caves, tunnels, cracks and crevices. In the United States, these habitats exist only in the Hawaiian Islands, with the vast majority of the 700 or so ponds and pools found on the Big Island.

“From the outside, it didn’t look like much, but inside it actually had all this tiny life,” says Chai, now the director of natural resources at the Four Seasons Hualalai Resort. “I remember asking myself, ‘What are these things? Where do they come from?’ I was fascinated and fell in love with these habitats right there. I had never seen anything like them before.”

According to the Center for Biological Diversity, ninety percent of anchialine (“near the sea”) ponds have been destroyed or altered by human activity. Early Hawaiians used the ponds, which vary in salinity according to their proximity to the ocean, for bathing and aquaculture as well as a source for cooking and even drinking water. Under natural conditions, these bodies of water have a life span of 300 to 400 years. But they are also extremely delicate: Populated by highly specialized flora and fauna, the ponds are especially susceptible to invasive species incursions. Alien grasses, shrubs and trees can easily choke off water flow. Discarded tropical fish can devour the resident shrimp and turn a thriving habitat into an algae-clogged mess within weeks.

Chai got his bachelor’s degree in geography before doing graduate work in coastal geology at UH-Manoa, studying the anchialine ponds outside of Hilo. He spent four years surveying, cataloguing and excavating the ponds along the coast and in the process became one of only three people in the world studying anchialine ponds. This expertise led to a busy consulting business as developers purchased property along the island’s lava-strewn Kohala Coast, which is dotted with the ponds and pools.


 

 
The teaming ecosystem of King's Pond
is easily visible.

In 1990, Chai was hired by the Kajima Kona Company to survey its recently purchased oceanside property at Ka‘upulehu, once home to a small Hawaiian fishing village and an ancient fishpond known as Waiakauhi. Kajima officials had razed the beginnings of the previous developer’s high-rise hotel. They wanted to build a resort that had a lower impact on the environment, but they didn’t know what kind of environment they were working with.

According to Chai, Ka‘upulehu was known for being a very productive fishery and the ponds helped support the community. However, over the years following Western contact, the residents slowly moved to Kona and other more populated and hospitable areas on the island. The last inhabitants vacated the area approximately seventy years ago, leaving their ponds to fend for themselves.

Where Waiakauhi once stood, Chai found a weed- and tree-filled mess. “There was a little wet spot, maybe ten to fifteen feet in diameter, and it was covered with kiawe trees, Christmas berries and filled with mud,” says Chai. “For two years, I surveyed and cleared out the area, step by step. I didn’t have any maps or even stories to work off of. I just hacked through the kiawe forest, following the outlines of the ponds, most of which were dry.”

Chai would eventually find thirteen ponds, eight of which were severely degraded. Shortly thereafter, he was asked to draft a plan to restore the area and then to direct the excavation. It was an extensive, three-year effort, which took place simultaneously with the construction of the resort. Chai and his crew removed kiawe and mangrove forests as well as alien grasses and shrubs. They then reseeded the ponds with sediment from existing anchialine ponds and then watched as nature took its course.

“Once we took out all the alien species, the ‘opae ‘ula [a tiny native shrimp] came back,” says Chai. “They live in the cracks and crevices and cleaned the place for us. When we got an algae bloom, we put in awa (milkfish) and mullet and they cleared that up. What normally would take five to six years naturally, we were able to do in two.”

When the Hualalai Resort opened in 1996, Chai had helped design and construct a complex system of thirteen natural anchialine and five man-made aquaculture ponds; a lagoon; and a 2.5-acre lake along the resort’s golf course that both processes wastewater and is a working aquaculture farm, serving as home to thousands of moi (threadfin), Pacific white shrimp and oysters. After everything was in place, the resort asked Chai to stay aboard and oversee the operation with a staff of five. (For his part, Chai deflects all credit for the effort’s success, instead crediting his staff and the resort’s management team.)


 

 
Under natural cconditions, anchialine
ponds have a life span of 300 to 400 years,

but they are also extremely delicate:
When David Chai first surveyed the

Ka‘upulehu area in 1990, Waiakauhi Pond
was a weed and tree choked mess. Today

it is a thriving ecosystem.

Without a doubt, Chai’s most eye-catching creation is the King’s Pond, a stunning, 1.4-million-gallon, self-contained saltwater lagoon, set amid the Hualalai Resort’s low-rise bungalows. Resort officials originally wanted an elegant plunge pool for guests to cool off between sunbathing sessions, but Chai, a longtime marine fish enthusiast, proposed a fish-filled lagoon in which guests could snorkel as well as wade. Today, Day-Glo yellow tangs, dinner plate-sized butterfly fish and brooding, torpedo-like awa are among the 4,000 fish from eighty to ninety different species that inhabit the King’s Pond.

For the pond, Chai designed an ingenious and deceptively simple system to filter the water, which works much like a home aquarium. Tapping a nearby saltwater well, powerful pumps send 7,000 gallons of water a minute into the King’s Pond, while water is evacuated through drains buried beneath the sandy bottom. This overflow is then sent to the system’s other ponds. Eventually, the water, cleansed by natural processes in those ponds, makes its way back through the lava and is returned to the water table.

“It was a brackish water pond, but I thought why not make it an attraction and have it support marine life,” says Chai. “We have the advantage of being surrounded by saltwater wells and porous lava, so we don’t have to dump the water into the ocean.”

Last year, Chai and several colleagues were honored by the Environmental Protection Agency for another of his
innovations. Man-made Punawai Pond is located along the fairways of the Hualalai Golf Course’s fifth hole. Resort officials wanted the 2.5-acre lake to serve as an attractive water feature for the course but also to be able to clean marginal wastewater from the resort.

Chai worked with an engineering firm to create a “living machine,” a habitat of floating islands of native plants that naturally cleanse the water. He also added an aquaculture component to the lake. Today, Punawai yields thirty moi and fifteen to twenty pounds of Pacific white shrimp a week, not a huge harvest, but enough to help supply the resort’s restaurants.

Although it doesn’t have the eye-candy or the output of some of his other bodies of water, Waiakauhi Pond may be the most beautiful and important one of them all. The fully restored, two-acre fishpond sits on the edge of the resort, between the golf course’s fairways and the tranquil Pacific Ocean. Even to the untrained eye, it is quickly apparent that Waiakauhi is teeming with life. On the shoreline, native grasses grow wild while awa and mullet swim in small schools just below the surface. Somewhere deeper, white ulua are on the hunt, scattering small schools of aholehole and minnow.

In the middle of the pond are several islands, which are now home to endangered Hawaiian stilts. In ten years, sixteen breeding pairs have produced twenty offspring. The latest pair of young birds hatched last May.

“We were really surprised how quickly the area recovered. We just let the native plants go wild and take hold, and today the whole thing requires relatively little maintenance, maybe cutting something back here and there,” says Chai. “What is amazing is that the water that comes out of here is a lot cleaner than what goes in. It’s like a giant liver. These ecosystems can easily handle an extra nutrient load.

“We’re a resort, but something like this can be easily duplicated in a lot of places,” continues Chai. “It’s really a matter of integrating development with the natural features, wherever you are. It’s about taking care of our environment and culture,
knowing that you’re trying to do things the right way.” HH