Koolaupoko | Images of Old Hawaiʻi

November 20, 2025 by Peter T Young 1 Comment

Coconut Grove

Kailua Ahupua‘a is the largest on the windward side of O‘ahu, and the largest ahupua‘a of the Koʻolaupoko District. From the Koʻolau ridge line it extends down two descending ridge lines which provide the natural boundaries for the sides of the ahupua‘a.

The natural environment includes the sand accretion barrier upon which Kailua Town stands, the mountainous upland terrain and alluvial valley of Maunawili, the largest fresh water marsh in Hawai‘i (Kawainui Marsh), another inland pond (Kaʻelepulu) and intermittent streams. (Cultural Surveys)

When the first Polynesians landed and settled in Hawaiʻi (about 900 to 1000 AD (Kirch)) they brought with them shoots, roots, cuttings and seeds of various plants for food, cordage, medicine, fabric, containers, all of life’s vital needs.

“Canoe crops” (Canoe Plants) is a term to describe the group of plants brought to Hawaiʻi by these early Polynesians. One of these was ‘niu,’ the coconut; they used it for food, cordage, etc.

Later, others saw commercial opportunities from coconuts.

In 1906, Albert and Fred Waterhouse were walking over sand dunes along the approximately one-mile wide by two-and-a-half-mile long area between Kawainui Marsh and the ocean, when they envisioned the idea of planting coconut trees there.

“During the week papers will be filed with the Treasurer for the incorporation of the Hawaiian Copra Co, having lands under (a 29-year) lease from Mr Castle. …”

“(The land) is … two-hundred and fifty acres adapted to the cultivation of cocoanut trees, of which it has twenty thousand, half of which are nearly three feet high and the balance recently planted.” (Pacific Commercial Advertiser, May 12, 1907)

“Samples of copra (dried meat of coconut) grown here have been forwarded to San Francisco …. The quality of the product is excellent, comparing favorably with that of the best grade received in that market, and the price per pound is satisfactory. So well pleased are the people on the Coast that they have signified a willingness to take all that can be shipped to them.”

“The copra is compressed and the extracted oil used in the manufacture of soaps, and as oils in the manufacture of high-grade paints. Another use to which it is put is the manufacture of shredded cocoanut, which is utilized by confectioners and bakers. The fiber is made into hawsers (ropes) for towing purposes.” (Pacific Commercial Advertiser, May 12, 1907)

They “leveled the sand dunes and smoothed out the sand hillocks,” and planted approximately 320-acres with over 130,000-coconut trees.

Many rows of ironwood trees were also planted as a windbreak and a fence had to be built to keep cattle out. (Drigot)

“The (coconuts were) secured from Kauai …. We have sunk one well and found water at a depth of 51-feet. It is our intention to sink about 25-such wells for irrigation purposes.”

“Our trees will be of the Samoan variety and will bear when about seven years old. There is very little labor needed. Eight men will take care of the whole place, so we will have no labor problem to contend with.” (Maui News, September 17, 1907)

“One of the uses to which copra is put and for which there has not yet been found an available substitute is in the production of salt water soap, soap that will lather and be effective in salt water.” (Pacific Commercial Advertiser, September 15, 1907)

Things looked up.

“George A Moore & Co, commission merchants, of San Francisco, see no reason why Hawaiian copra should not compete more than favorably with other South Sea copra in the mainland market.… (He noted,) We beg to call to your attention the large consumption in this market of dried cocoanut, commercially known as copra, which reaches as high as fifteen thousand tons per annum.”

“Most of our importations are brought from the Pacific and South Sea Islands, but having recently seen a small parcel which issued from the Hawaiian Islands of very good quality it occurs to us and we see no reason why large quantities of this could not be brought from the American island possessions, notably the Hawaiian Islands.”

“For your information we would say that the ripe cocoanuts are cracked open and exposed to the sun, whereupon the meat shrinks from the shell and the dried meat itself constitutes the commodity above referred to, which is today realizing in our market 3 3/8 c US gold.”

“Cocoanut plantations in the Pacific Islands for the production of copra have now become quite an extensive and profitable venture, and we have no doubt it would prove so to your planters. ” (Peters; Pacific Commercial Advertiser, December 17, 1908)

It didn’t last. … In 1916, the copra/coconut oil enterprise failed.

The Waterhouses sold their “Coconut Grove” to AH Rice, who planned a residential subdivision in the area. In 1924, Earl H Williams, of Liberty Investment Co, acquired 200-acres from Rice and began the subdivision process (the Coconut Grove Tract.) (Drigot) At the end of World War II, Kailua began a real estate and development boom.

As the landscape became urbanized, flooding became a problem. There are reports of major flooding in this area in the years 1921 and 1940. In 1939, Congress instructed the Army Corps of Engineers to conduct a survey of the Marsh area and to assess its value as a flood control basin.

Kailua town as a whole suffered a severe flood in 1951 and 250-people were forced to evacuate their homes in the area. The Oneawa Channel (Kawainui Canal) was under construction in 1952 to prevent the major flooding of the Kailua residential area situated on the edge of the marsh. Subsequent severe floods occurred in 1956, 1958, 1961 and 1963.

Finally, the “permanent” stage of the Federal-State Kawainui Flood Control Project, first targeted for this area in the 1930s, was completed in 1966. This project entailed “dredging the debris and widening the Kawainui Canal, and building a 9-foot high levee to hold back storm water and widening the inner canal”.

However, from December 1968 through January 1969, as much as 8-inches of water covered a large area from Oneawa Street to Kihapai Street. The levee and Canal had eliminated direct overflow from the marsh, but flooding still occurred. (Drigot)

In 1988, floodwaters breached the levee. it was later modified by the Army Corps and City in 1997 raising its height and constructing a concrete floodwall to address the 100-year flood level estimated for Kawainui Marsh. (HHF)

June 28, 2025 by Peter T Young 2 Comments

Podmore Fire Control

“There are strong arguments in favor of putting the principal harbors of the country in a state of adequate defense, even at very considerable cost. But the work should be done according to a well digested plan, which will give reasonable security that it will answer its purpose.” (New York Times, July 1, 1884)

Harbor defenses had constituted the primary element of the means employed by the Army for seacoast defense. Harbor defenses consisted of permanently installed guns of various calibers, which could be supplemented in an emergency by mobile coast artillery guns and controlled mine fields.

The Artillery District of Honolulu was established April 24, 1909 and consisted of Forts Ruger, DeRussy, Kamehameha and Armstrong (the District was renamed Headquarters Coast Defenses of Oʻahu.)

Following World War I and until the end of World War II, additional coastal armaments were constructed. Then, the Army mission was “the defense of Pearl Harbor Naval Base against damage from naval or aerial bombardment or by enemy sympathizers and attack by enemy expeditionary force or forces, supported or unsupported by an enemy fleet or fleets”.

Batteries at Fort Kamehameha, Fort Weaver and Fort Barrette (the latter two constructed in 1924 & 1935) completed pre-World War II coastal defense network for Pearl Harbor.

Batteries at Fort DeRussy and Fort Ruger were responsible for the defense of the South coast and Honolulu Harbor. While none of the large caliber guns were ever fired except in practice, the secondary anti-aircraft guns of coastal artillery units at Fort Kamehameha were credited with shooting down a number of attacking aircraft on the morning of December 7, 1941.

Following the Pearl Harbor attack, as part of the growing Coast Defense network, numerous Batteries and their associated Fire Control Stations were set up around the Islands.

A Fire Control Station is an observation and command center used to direct fire from gun Batteries on the coast. Fire Control personnel spot and determine where the guns should aim (typically working with others using triangulation;) Batteries have the guns to fire at the targets.

In 1917, Waimanalo Military Reservation was created (later renamed to Bellows Field in 1933;) with the outbreak of WWII, Bellows was transformed almost overnight into an important facility where aircraft were prepared for their duty in the Pacific Theater.

Part of the defense of the facility was Battery Wailea, located at Wailea Point (at the dividing line between Waimanalo and Lanikai.) Search lights were emplaced at the Battery. The Battery was operational from 1942 to 1945.

It was initially armed with two mobile 155-mm guns (about 6-inches, that could send 96-lb projectiles 17,400-yds,) later replaced with two 5-inch guns (58-lb projectile, 10,000-yd range) (later supplemented with two 3-inch guns (15-lb projectile, 11,100-yd range.))

Battery Wailea was supported by Fire Control Station Podmore. Podmore, completed February 28, 1943 – named for a nearby triangulation station, supported other armaments and was made up of two stations: a single story North structure (29A) and a double-tiered South station (29B & 29C.) (Bennett)

Pedestals in the bunkers were mounts for high-powered optical instruments for determining azimuth and range of ocean vessels.

An observer and recorder staffed each observation station. Data obtained from the observer’s optical instrument was telephoned by the recorder to the assigned gun battery by a local-battery operated telephone. (Bennett)

The troops manning the site slept and lived in tents in shifts on the slopes. Water and power lines were brought up from below to serve the bunkers and tent quarters from the Lanikai side of the Kaʻiwa Ridge.

The Podmore stations were located in the South Sector of Oʻahu’s two defense sectors, and tactically assigned to the Harbor Defenses of Kāneʻohe Bay located in a tunnel system dug into Ulupaʻu Crater on Mōkapu Peninsula.

The harbor defenses were set up to protect the vital Navy seaplane and landplane base at the Kāneʻohe Bay Naval Air Station built on the Mōkapu Peninsula. (Bennett)

After end of WWII, the parcel was declared surplus by the General Services Administration (GSA) and was offered for sale to the highest bidder. Both the State and the City & County did not offer to acquire the parcel and the property was sold to a private individual. (DLNR)

Today, a hiking trail takes you to the Fire Control Station.

The Ka‘iwa ridgeline may be accessed by one of two legal routes: the first is a City and County of Honolulu public access right-of-way that was established as a condition of subdivision approval for the Bluestone condominiums. The other access point is a State-owned trail corridor that was purchased for use by the Nā Ala Hele Trail and Access Program (Governor’s Executive Order 3610, 1994). (DLNR)

Most folks call the Podmore Fire Control bunker the Lanikai Pillboxes; a misnomer. As noted, the bunkers were built as an observation and command center for Battery Wailea and observation for Bellows Field.

A pillbox is a reinforced guard post, normally equipped with openings through which to fire weapons. The Podmore Fire Control Station was for observation, not weaponry.

In 2024, DLNR published as Final Environmental Assessment that calls for actions “to improve the Ka‘iwa Ridge Trail by implementing a trail management plan concurrently with the installation of physical improvements to the trail corridor.”

“Proposed improvements include a combination of surface treatments, erosion control measures, fencing or other barriers, and trail signage throughout the trail corridor.”

Lanikai Fire Control-(saito)

Waimanalo to Alala Pt-t4379_dd-1928-noting Podmoreequipment, not guns-punynari

Trail to lanikai-bunkers-punynari

The ‘Mokes’ from Fire Control Station Podmore

Start of the hike – lanikai-bunkers-punynari

lanikai-bunkers-punynari

Kailua and Fire Control Station Podmore

Heading up the trail to lanikai-bunkers

Almost to the top of trail to lanikai-bunkers-punynari

Example of 155mm gun (not specifically at Battery Wailea)

Example of 155mm gun (not specifically at Battery Wailea)-1943

Fire Control Station Podmore

Fire Control Station Podmore-(NotSoGreatHiking)

Fire Control Station Podmore_punynari

Fire Control Station Podmore-pedestals for viwing equipment, not guns-punynari

Fire Control Station Podmore-punynari

April 7, 2025 by Peter T Young 3 Comments

Campos Dairy

During the mid-1800s, Queen Kalama, wife of Kamehameha III, and Judge CC Harris attempted to establish a sugar plantation on the majority of lands in Kāneʻohe and Kailua. When this venture failed in 1871, Judge Harris obtained title to the lands, which he transferred to his daughter Nannie R Rice.

JP Mendonca leased the lands from her and, on November 1, 1894, incorporated Kāneʻohe Ranch, for the purpose of raising cattle. A foundation herd of Aberdeen-Angus cattle formed the basis for a commercial herd of between two and three thousand head.

The “wet-lands” on the property were leased to Chinese for rice cultivation. In 1907, James B Castle acquired the capital stock of Kāneʻohe Ranch Company Limited, and in 1917 his son Harold KL Castle eventually purchased the lands from Mrs Rice.

The cattle industry remained an integral part of the ranch’s operations until World War II, with the herds in the early days being driven by cowboys over the Pali to be butchered in Honolulu. Military operations on the ranch lands became so extensive during World War II that the cattle industry was discontinued.

The 12,000-acre ranch, when it came under the direction of Mr Castle, also engaged in the cultivation of pineapple. However, because of the extensive rainfall on this side of the island, pineapples proved uneconomical and in the 1920s were discontinued. Likewise, because of competition from California, rice farming declined in the 1930s. (NPS)

Parts of the area became used by dairy farms … that leads us to the Campos clan.

One of the biggest dairies on the Island was Campos Dairy in Kailua (it was also called LW Campos Ranch and Eagle Rock Dairy – because there was a large lava outcrop in the middle of a flat field shaped like an eagle.) (Miranda)

Rafael Marfil Campos was born in Velez, Malaga, Spain on June 30, 1860 to Antonio Gonzales Campos and Ana Robles Marfil. In 1883 he married Irene Rudea Lopes of Macharaviaya, Malaga (she died in 1889); his second wife was Carolina Escano Lopes, of Benagalbon, Malaga (she died in 1894).

Campos had emigrated from Spain to Cuba in 1893; there he lost his worldly possessions in the revolution against Spain. In 1897, Campos married Maria Gallardo Claros de Macharaviaya. He then moved to Puerto Rico in 1900.

After returning to Spain and living there for a while, he came to Hawaiʻi in 1907.

1912 newspaper reports show Campos was farming in Kapahulu (near where the Honolulu Zoo is situated.) Campos “is an expert farmer who arrived here from Spain in the immigrant steamer Heliopolis …”

The newspaper was reporting on losses he suffered on his vegetable and fruit farm due to fruit flies attacking his Chile pepper. He noted, “If something is not done in regard to the fruit fly, our islands will be ruined as far as vegetables and fruits are concerned.” (Hawaiian Star, June 6, 1912) That same year, recorded transactions note he also sold cows.

During the 1920s and 1930s several dairymen moved from Kapahulu to the windward side because large tracts of land had been abandoned by Libby, McNeill & Libby, following the closing of their pineapple cannery in Kahaluʻu.

Campos Dairy farm appeared in 1925 along the mauka side of Kailua Road (reportedly, one of the first to make the move to the Windward side.) It was where Target and the Ka Malanai Condominiums are today.

Leasing land from Kāneʻohe Ranch, Campos also bought land around Kaʻelepulu Stream. A 1994 MidWeek cover story said the Campos land included 800 to 1,000-acres, where a herd of 1,000 to 1,200-cattle roamed. (Star-Bulletin)

The senior Campos “retired from the diary business in 1937, turning his interests over to his sone, Lawrence. He kept his hand in, however, by maintaining a flock of 600 Rhode Island Red chickens as a hobby.” (Adv, Mar 1, 1946) (Another son, George, also was involved with management of the dairy.)

Campos sold milk to the Dairymen’s Association (a cooperative formed in June 1897 when seven O’ahu dairy farms joined forces (Waiʻalae Ranch dairy, Kaipu Dairy, Mānoa Dairy, Honolulu Dairy, Nuʻuanu Valley Dairy, Woodlawn Dairy (Mānoa) and Kapahulu Dairy.)) (In 1959, the Dairymen’s Association, Ltd name changed to Meadow Gold Dairies Hawai‘i.)

Due to disagreement in a new policy, Campos was ready to go out on his own. “The decision to go into his own milk and dairy products business was made, according to Mr Campos, when Dairymen’s refused him the renewal of the flat-rate contract … he was asked to join the pool to which most of the milk producers now belong”. (Honolulu Record, September 7, 1950)

Lawrence Campos of the Eagle Rock Dairy planned to go into distributing milk in competition with the Dairymen’s Association. This brought speculation of a “milk price war.”

“Campos is working closely with owners of the Hygienic Dairy in his plans to organize a million dollar company … Hygienic has also had disagreement on a contract renewal with Dairymen’s.” (Honolulu Record, September 14, 1950)

By 1952, Campos is noted as “processing and selling milk;” that year, Foremost bought Campos Dairy Products, Ltd, as well as several other dairies and made its entrance into the Honolulu milk market. Operations were later transferred to Waimanalo. (FTC)

In the late-1960s, negotiation were underway by respective parties to acquire the Campos lease on the Castle/Kāneʻohe Ranch lands – the plan was to develop the pasture into apartments, condominium and commercial uses (one party offered $1,370,000 to purchase the Campos Ranch leases with Castle.)

Hawaii’s current dairy industry is tiny compared to what it once was. The state was self-sufficient in milk until 1982. Dairy operations could once be found across Oahu — from Hawaii Kai to Kapahulu and Waianae.

But in 2022, Hawaii had 633 dairy cows spread across 22 farms, according to the USDA. And more than half belong to Cloverleaf Dairy. In the 1960s, the state had about 50 dairies; now, there is one – the 350-cow Cloverleaf Dairy. (Heaton; Civil Beat)

February 16, 2025 by Peter T Young Leave a Comment

Pāhonu

Honu neʻe pū ka ʻāina
The land moves like the turtle.
(Land passes slowly but inexorably from owner to heir.)
(Pukui)

From its earliest period of occupation, the Waimānalo Bay region was an extensive agricultural area, featuring taro farms that used the traditional Hawaiian loʻi (pondfield) cultivation system.

Taro was grown in the lowlands, irrigated with water from Waimānalo Stream, as well as on terraced sections that were watered by the small streams and springs flowing out of the Koʻolau Range.

These terraced sections extended for nearly 2-miles in a semicircle at the foot of the mountains around the broad base of the Waimānalo valley. By the 1850s, the area’s fertile soil provided not only taro but also breadfruit, mountain apple, kukui and coconut trees, sweet potatoes and sugar cane. (NPS)

In addition to the agrarian-based economy, several fishing villages dotted the bay’s shoreline. Two of the best-known villages in the area were Kaupō and Kukui. Kaupō was on a small peninsula opposite Mānana Island (Rabbit Island) and just northwest of Makapuʻu Beach Park (where Sea Life Park is located.)

The village may have been depopulated during the early-1800s and probably was repopulated during the early-1850s when a disastrous smallpox epidemic struck Honolulu and Hawaiians settled temporarily in the Waimānalo Bay region to escape its ravages.

The small fishing village of Kukui was further northwest, along the bay in the Kaiona Beach vicinity near Pāhonu Pond (‘Turtle enclosure’) – a prehistoric walled enclosure where it is said that turtles were kept for the use of Hawaiian chieftains. (NPS)

Before we go there, let’s look at some findings of Dr Marion Kelly where she speaks of three main technological advances resulting in food production intensification in pre-contact Hawai‘i: (a) walled fishponds, (b) terraced pondfields with their irrigation systems and (c) systematic dry-land field cultivation organized by vegetation zones.

The Hawaiian walled fishpond stands as a technological achievement unmatched elsewhere in island Oceania. Hawaiians built rock-walled enclosures in near shore waters, to raise fish for their communities and families. It is believed these were first built around the fifteenth-century.

The general term for a fishpond is loko (pond), or more specifically, loko iʻa (fishpond). Loko iʻa were used for the fattening and storing of fish for food and also as a source for kapu (forbidden) fish.

Samuel Kamakau points out that “one can see that they were built as government projects by chiefs, for it was a very big task to build one, (and) commoners could not have done it (singly, or without co-ordination.)” Chiefs had the power to command a labor force large enough to transport the tons of rock required and to construct such great walls.

The fishponds just described refer to aquaculture to grow fish – they were found throughout the Islands; however, at Waimānalo, Oʻahu, the only remaining aquaculture of green sea turtle known to have been carried out by the early-Hawaiians involved a coastal pond named Pāhonu that was used to maintain turtles until they were ready to be eaten. (NOAA)

The green sea turtle is the principal marine turtle species in the Hawaiian Islands. Common names used in the Hawaiian Archipelago include honu, green turtle and green sea turtle. They are herbivorous, feeding primarily on seagrasses and algae. This diet is thought to give them greenish-colored fat, from which they take their name. (NOAA)

In Hawaiʻi, as throughout Polynesia and other islands in the pacific, sea turtles have always been a traditional part of the local culture and have historically been revered as special and sacred beings. (Luna)

“There was once a chief who was so fond of turtle meat that he ordered a sea wall be built to keep captured turtles from escaping. Every turtle caught by a fisherman was put into this enclosure. No one else was allowed to partake of turtle meat under penalty of death. No one dared to eat turtle as long as the old chief lived.” (Pukui; Maly)

Kikuchi in his “Hawaiian Aquaculture Systems,” notes that “An early visitor to Waikiki area remarked that the ruling chief of Oʻahu, Kahekili, ‘mentioned also some others where he had a quantity of turtle.’”

“… We walked back to Mr. Castle’s house, where we sat on a long bench outside, facing the sea. There Aiona told me the story of Pa-honu, an enclosure for turtles that was once located back of Mrs. Wall’s present home.” (Pukui; Maly)

Pāhonu, the offshore pond (500 feet long, 50 feet wide,) is just south of Kaiona Beach Park fronting the shoreline; a line of stones, submerged at high tide, but visible at low tide, notes its location. (Pukui)

Kaiona Beach Park, a small four-acre park at the south end of Waimānalo Bay, is a popular camping site that has also been used for many years as a community boat anchorage.

In 1998, residents of Waimānalo built a boat ramp in the south end of the park, the only paved ramp in Waimānalo. They also placed a monument to Hawaiian fishers from their community near the ramp. Kaiona means “attractive sea. (Clark)

The beachfront residence named Pāhonu inland of the pond was used from 1980 to 1988 as the base of operations for the popular television series, Magnum PI. A surf site borders a small channel through the reef and is also known as Magnums. (Ulukau) The ‘Magnum’ house has been removed and other houses are it its place.

Next to Pāhonu is Kaʻakaupapa (shallows at the right.) The old saying of this place was, “Papa ke kānaka, papa nā mea a pau”—“Multitudes of people, multitudes of gods, all in multitudes.” (Aiona, Informant, Sept. 14, 1939; Cultural Surveys)

Nearby is the Shriners Club, a private clubhouse that opened on April 20, 1931. Popularly known as Shriners Beach, it is used for a wide variety of events, including wedding receptions, birthday parties and other social gatherings. (Clark)

The green turtle is listed as endangered by the International Union for the Conservation of Nature. In 1978, the Hawaiian population of the green turtle was listed as threatened under the U.S. Endangered Species Act of 1973. NOAA Fisheries and the U.S. Fish and Wildlife Service (USFWS) have joint jurisdiction for green sea turtles.

State and Federal laws prohibit harassing, harming, killing, or keeping sea turtles in captivity without a permit allowing these activities for research or educational purposes. Divers should be aware that riding turtles is illegal and puts these animals under stress.

November 21, 2024 by Peter T Young Leave a Comment

It’s Raining … Inside

The Koʻolaupoko moku (district) encompasses lands from Kualoa Point to Makapuʻu Point. Encompassing 43,598-acres (68-square miles,) Koʻolaupoko makes up approximately 11-percent of Oʻahu’s land mass.

The Koʻolau Mountain Range forms the inland (mauka) boundary of the district. The ridge elevation generally ranges from 2,500 to 2,800-feet; Kōnāhuanui, the tallest peak on the Koʻolau Mountain Range (3,150-feet) is found in Koʻolaupoko. (BWS)

Koʻolaupoko is the remnant of the Koʻolau volcano. Eruptions forming the mountains occurred approximately 2-million years ago and left lava flows that layered over each other. Magma pouring out of fissures in the volcano solidified in the narrow cracks; the rock that is created is much denser and much less permeable than the surrounding porous lava flows.

These dense, usually vertical geological structures are known as volcanic dikes. These dikes form wall-like areas that can capture and contain water.

Trade winds, which blow over the Pacific from the northeast across the Hawaiian Islands, bring large quantities of moist air to the Koʻolau Range. When these winds are deflected up and over the range, the water vapor condenses into clouds and falls as rain.

The rainfall does one of three things: (1) it runs off, eroding the land, forming valleys and gouges in the mountain slopes (and also creates some spectacular periodic waterfalls;) (2) wets the land surface, shallow infiltration saturates the uppermost soil layer and replaces soil moisture used by plants and then is absorbed by the vegetation and/or evaporates (evapotranspiration;) or (3) it percolates into the ground (slowly sinks into the ground and becomes groundwater.)

For the latter, it takes about 9-months for the rain, now groundwater, to seep down through cracks and permeable materials in the mountain; much of the groundwater ends up contained in dikes inside the mountain.

As these dike compartments become filled with water and overflow the dike edges, sometimes the water emerges at the surface as springs or streams.

Dike water is good for drinking water.

Development of dike-impounded reservoirs for domestic water offers two basic benefits: (1) the water level is typically high (limiting pumping (as in energy to pump water up wells) and allowing gravity to distribute to the needs at lower elevations) and (2) the reservoirs are isolated from saline water.

Groundwater impounded by dikes in the Koʻolau Range is a major source of water for the island of Oʻahu, and many tunnels have been bored into the range to develop it. (USGS)

The typical sequence of excavation of a high-altitude tunnel starts with the removal of a zone of weathered rocks, either by tunneling or trenching and is followed by penetration of dike intrusions in the basalt rock.

As tunneling advances farther and farther through the dikes and basalts, the contained dike water leaks and water flow increases, often in instantaneous jumps when key restraining dikes are punctured, until either a single dike, or a series of them, releases such a large volume of stored water that excavation must be halted. (Mink; USGS)

When a tunnel is bored into a dike-water reservoir, if allowed to flow freely, it will drain water out of storage. Over the course of water exploration in this area, several dikes were struck.

The reduction of dike-confined groundwater storage caused by construction of eight tunnels in Oʻahu has been estimated at 25,800-Million gallons, equivalent, then, to the total ground-water withdrawal on Oʻahu for about 60 days. (USGS)

Little consideration was given to the storage potential of dike compartments tapped and dewatered by water-development tunnels until a bulkhead was placed in a Waikāne tunnel of the Waiāhole system in 1934 to stop the draining and allow the dike to refill with water (about 40 years after high-altitude water-development tunnels were first constructed in Hawaiʻi.)

The bulkhead at Waikāne held back some water in storage, but not in sufficient volume to be considered successful. Use of the Waikāne bulkhead was discontinued, but other attempts at bulkheading were tried elsewhere, also without much success.

That changed on February 8, 1955. A 12-foot dike 1,600 feet into the Waiheʻe tunnel was penetrated and water gushed out at an initial rate of about 2.5-mgd (million gallons per day.) A bulkhead was built to contain the water.

The bulkhead held and the concept of inducing and controlling storage was resoundingly proved with the placement of the bulkhead in Waiheʻe tunnel. The storage above the tunnel in Waiheʻe Valley has been estimated at 2,200-Million gallons. (Mink; USGS)

In Koʻolaupoko, fresh water comes entirely from precipitation along the Koʻolau Mountain Range; Waiheʻe provides much of the drinking water to Windward Oʻahu, from Kahaluʻu to Kailua.

The Honolulu Board of Water Supply recently drilled an inclined well to tap dike-impounded water. This technique permitted the development of dike impounded water without the large initial and uncontrollable waste of stored water common to prior development by tunneling.

Dike tunnel systems are also at Waimānalo, Luluku, Haiku, Kahaluʻu, Pālolo, Mānoa and two Waianae tunnels, as well as in the Kohala region of the island of Hawaiʻi and in West Maui.

Oh, It’s Raining … Inside (?)

While the bulkhead holds the dike water, along the Waiheʻe tunnel into the Koʻolau, whatever the weather outside, rainwater (now groundwater) that missed the dike continues to make its downward percolation through the mountain, through cracks in the ceiling … producing a constant ‘rainfall’ for all in the darkness of the tunnel to the Waiheʻe bulkhead.