Nate’s Adventures: Mānoa Falls, Makiki Falls & Wāwāmalu
by Nate Yuen | Reading time: 5.5 minutes
Mānoa Falls Status
I hiked to Mānoa Falls this morning. A weather system reached Oʻahu two days ago. It's been raining over the Koʻolau Mountains. It rained hard this morning and I got soaked hiking to Mānoa Falls. Lots of water coming down. Muddy run-off the color of chocolate milk -- plunged down Mānoa Falls.
When it rains hard, the 100 foot falls can turn into a torrent of water. But in the dry season, the flow reduces to a trickle. Mānoa Falls is fed by Waihī Stream -- lit. trickling water -- which drains the portion of Kōnāhuanui that overlooks Mānoa Valley. I hope we get more rain this summer -- many leeward and coastal areas are already thirsty.
On June 24, 2022, a weather system reached Oʻahu. It rained hard over the Koʻolau Mountains last night and this morning. Rain clouds rained and I got soaked hiking to Mānoa Falls this morning. Muddy run-off the color of chocolate milk -- plunged down Mānoa Falls.
On June 8, 2022 we turned the corner into kauwela -- the dry season. There has been noticeably less clouds over the Koʻolau Mountains. The water flow in Mānoa Falls has diminished.
On May 20, 2022 a weather system brought more rain to the Ko‘olau Mountains and lots of water plunged down Mānoa Falls.
On May 6, 2022 a weather system reached Oʻahu and brought rain.
On April 6, 2022 the Koʻolaus have been getting consistent windward and mauka showers.
On March 17, 2022 it is apparent we were experiencing a dry wet season.
On February 28, 2022 Mānoa Falls was reduced to a trickle. We did not have rain since the big rain event from Dec 24 to Jan 1.
Makiki Falls & Springs
I led a Sierra Club hike to Makiki Falls and Springs on the Na Ala Hele System of Trails. The purpose of the hike was to reconnect people with nature, show where Oʻahu's drinking water comes from, and what we can do to protect this precious resource.
We took a group selfie before the hike: Nate Yuen, Randy Ching, Karen Shishido, and Travis Fukumitsu.
Randy and I arrived a little early so we stopped by the Makiki Pumping Station operated by the Honolulu Board of Water Supply which taps the Makiki Aquifer for drinking water. This is where our drinking water is held after pumping it from underground for distribution to neighborhoods in pipes.
The plan was to hike the loop highlighted in yellow on these 3 trails: Kanealole Valley, Makiki Valley, and Maunalaha.
We stopped by a big ʻōhiʻa ʻai -- mountain apple -- tree loaded with fruits. The fruits are developing and will not be ripe for another month or so.
Three streams: Kanealole, Moleka, and Maunalaha converge into Makiki Stream.
Ulu trees -- breadfruit -- grow alongside the stream.
As do maiʻa -- bananas.
The source of the streams are groundwater under Tantalus. An aquifer inside the mountain captures and releases water into the streams.
We passed rock walls covered mosses and ferns. The sign indicated that these walls are old Hawaiian walls.
As we hiked up the Kanealole Trail we hiked alongside pipes partially buried in the ground which divert water from the stream to irrigate sugar cane and other crops once grown in Makiki Valley.
We reached the side trail where a dam structure is built across the stream to divert water.
ACK! I was dismayed to see that a new scheflera tree had fallen into the waterfall -- need to go back with a chainsaw. The waterfall cascades in 3 sections -- with a combined height of about 90 feet.
We climbed up to the upper part of the water which falls for about 30 feet.
We lingered for a while to enjoy the waterfall. Crashing water emits negative ions which is said to promote relaxation and a sense of well-being.
We then made our way to Makiki Springs. Rainfall over the Koʻolau Mountains and Tantalus seeps into the earth and percolates through layers of lava rock, where they are trapped in dike compartments.
Groundwater seeps out of the earth and is the source of the streams. As we enter the dry season we need to conserve our drinking water.
We looped back across the bridge to return the way we had come. I will be leading this hike again on Saturday, July 30, 2022. You can sign up here.
Native Ecosystem Restoration at Sandy Beach
On May 30, 2022, the Sierra Club of Hawaiʻi helped kick-off World Oceans Month with Parley for the Oceans to restore the native coastal ecosystem at Wāwāmalu – Sandy Beach in East Oʻahu.
We met at Sandy Beach in East Oʻahu where the city moved large boulders to block vehicles from getting into areas where partiers had been gathering at night to burn wooden pallets. There are hundred of nails in each wooden pallet, and the sand contains thousands of rusty nails from the burning pallets over the decades. The partiers also leave behind lots of trash. Now the boulders have been installed, the area is not accessible to vehicles. Our goal is to restore the habitat so the native plants can rejuvenate.
Kahi Pacaro (on right) is the Director of the Hawaiʻi Parley for the Oceans. The national Parley for the Oceans organization is celebrating its 10th year caring for the oceans.
Reese Liggett (on left) gave instructions to the group on removing invasive species, spreading native seeds, and installing passive barriers to reduce human traffic where the native ecosystems are recovering.
Wayne Tanaka (on right) and Jonee Peters (in middle) are among about 30 volunteers to showed up for the work day.
Much of the work entailed removing invasive species from the stands of naupaka and milo.
We used picks to dig out the haole koa which grow deep into the ground. The first step is clearing around the haole koa so we can access the roots.
We had lots of help removing invasive species.
The deeply rooted haole koa required much more effort to remove. Fortunately we had lots of help.
Once the area is clear and the roots are accessible, we used a puller bar -- giant wrench -- to pry the deep roots from the ground.
The puller bar allowed us to use leverage to pull the haole koa plants out by the roots.
We were blessed to have young strong volunteers who toiled in the hot sun to pull out the roots.
After we removed the haole koa, we spread seeds of native plants, so they will germinate at the next big rain.
Lots of haole koa roots to pull out.
We also created passive barriers by pounding rebar into the sand, covering the rebar with a wooden post, and putting rope between them.
The passive barriers discourage people from going into areas where we want the native ecosystem to recover and proliferate. Here's hoping the native plants make a comeback.
