He’eia Fishpond is our next door neighbor located immediately to the south of He’eia State Park. This amazing icon of ancient Hawaiian culture is one of the last true remaining ancient Hawaiian fishponds on windward Oahu!
This wall was originally built 600-800 years ago by the Hawaiians to be used as a self-sustaining fish farm. They built this wall strategically right on the edge of where He’eia stream empties into the bay. An estuary ecosystem like this was ideal so they could divert fresh water from the stream into the fishpond, thereby raising the oxygen level of the water inside the pond, which made it easier for the algae and plant life to grow for the fish to eat.
The fishpond has many openings on all sides with gates called makaha that would allow ocean water and fresh water to flow freely in and out with the tide, and also allow small fish to enter into the pond from the bay. Once inside the pond, the fish were free to eat until they grew too large to get back out.
Fish inside the pond will generally swim out against the tide when it is coming in through the gate, but then not be able to get out through the makaha on the outside of the wall. When it was time to harvest some fish, the Hawaiians just had to wait for the right tide when the fish would swim out, and then insert another barrier on the inside of the opening in the wall. Now all the fish are trapped in a very small area the width of the wall itself, making it easy for them to be harvested.
The wall itself is made of volcanic rocks that were originally carried great distances from further inland, and passed along by hand to get them all the way to the water’s edge. This must have been an unbelievably difficult process. Imagine how long it would take to build a wall like this that is over one mile in circumference! But once built, this marvel of ancient Hawaiian engineering was a self-sustaining fish farm that provide food for its community and neighboring communities for generations! Coral rubble was also used to fill in the wall as that is lighter, less dense, and found much closer by.
Over the course of almost a century, invasive mangrove trees spread throughout the area and broke the wall and other structures apart. At some point in Hawaii’s development these fishponds ceased to be used anymore as they traditionally were, and most fell into a state of disrepair. Many have all but ceased to exist at all.
He’eia Fishpond is not only one of the few remaining of its kind, it is also unique in its size and shape. Most fishponds would have extended out from one point on the shoreline and then ended at another point further down the shoreline. He’eia Fishpond as built as a complete circle on the edge of the stream. With a circumference of over one mile, and an area of 88 acres, this is also one of Oahu’s largest fishponds. Just to put that into perspective, He’eia State Park is only 18 acres!
Today He’eia Fishpond is private property. It is being restored and preserved as the priceless artifact of Hawaiian culture that it truly is. It is not open to the public currently, and kayakers are not allowed to land or walk on the wall, or go inside the pond. It is possible to kayak into the stream, especially at higher tides. And kayaking is absolutely the best way to get a close up look at this truly special place!