Waihee | Images of Old Hawaiʻi

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.

In Europe, Great Britain defeated France in the Seven Years’ War (1756-1763,) becoming the dominant power in Europe, North America and India. The war cost a lot of money; to raise funds Britain decided to levy taxes on the Colonies on the American continent.

For instance, the passed Quartering Act (required the colonies to provide barracks and supplies to British troops;) Stamp Act (taxed newspapers, almanacs, pamphlets, broadsides, legal documents, dice and playing cards;) Sugar Act (increased duties on non-British goods shipped to the colonies) and Currency Act (prohibited American colonies from issuing their own currency.)

This marked the beginning of Colonial opposition to the British (1765) and Colonists cried out against ‘taxation without representation.’

Turmoil was in the Islands, as well – some folks on Maui were also feeling that they were not being treated fairly; in addition, a power struggle was emerging.

Wailuku was considered a Royal Center (politically, ceremonially and geographically important during traditional times) with many of the chiefs and much of the area’s population residing near or within portions of ‘Īao Valley and lower Wailuku. (FWS)

The period immediately preceding contact with the Europeans was one of considerable upheaval and conflict. (FWS)

After the death of Kamehamehanui (the late king of Maui,, which happened about 1765, Nāmāhana (the widow queen of Kamehamehanui) married Keʻeaumoku. (Fornander)

Nāmāhana’s brother, Kahekili, then became King of Maui, was displeased that Nāmāhana had taken Keʻeaumoku for her husband, and he became Keʻeaumoku’s enemy.

Nāmāhana and Keʻeaumoku lived at the large and fertile land of Waiheʻe.

Some people on Maui felt that the abundance of resources would have allowed all to be well fed; they felt they were not getting their share.

In particular, Kahanana (at the time, a lesser chief in Waiheʻe) was neglected by Keʻeaumoku and his court when the chief of Waiheʻe distributed fish, after fortunate catches, among the subordinates and warriors living on the land. (Fornander)

Kalākaua writes that “Kahekili induced Kahanana … to embroil Keʻeaumoku in a difficulty with his own people.”

One evening Kahanana killed three of Keʻeaumoku’s men. An insurrection arose and Kahekili, who was in the vicinity, took the side of Kahanana.

The resultant Battle of Kalaeʻiliʻili (c. 1765) was fought because the rich agricultural resources of the Waiheʻe River Valley and the offshore marine resources were being unevenly distributed by the chief Keʻeaumoku and other Molokai chiefs.

A general fight ensued between the Kahanana party, being supported by Kahekili, and Keʻeaumoku. Keʻeaumoku and his chiefs maintained their ground for some days, but were eventually overmatched, beaten and obliged to flee. (Fornander)

The Battle reportedly marked the beginning of Kahekili’s reign and Keʻeaumoku and the Molokai chiefs were driven out of Waiheʻe.

But the anger of Kahekili pursued the fugitives. Invading Molokai, he engaged Keʻeaumoku and his Molokai allies in a sea-fight and Kahekili was again victorious. The naval engagement off Molokai is called the battle of “Kalauonakukui.” (Fornander)

Keʻeaumoku fled to Hāna, where Mahihelelima, the governor under Kalaniʻōpuʻu, received him and his wife and entertained them at Kaʻuiki. (Fornander)

At Kaʻuiki, Keʻeaumoku appears to have found a short repose in his turbulent career; he was not heard of again for some years. It is probable that he made his peace with Kalaniʻōpuʻu and was permitted to remain at Hāna. (Fornander)

It was later, there at Kaʻuiki, Hāna, Maui, in about 1768, that Keʻeaumoku and his wife Nāmāhana had their first child, Kaʻahumanu, future and famous Queen of Kamehameha the Great.

Again, several years pass by with Kalaniʻōpuʻu still holding portions of the Hāna district on Maui and the great fort of Kaʻuiki; but about the year 1775, the war between Hawaiʻi and Maui broke out again. (Fornander)

Kahekili successfully defended his capital in Wailuku throughout the 1770s, until his defeat at the hands of Kamehameha’s forces. (FWS) (Kamehameha went on to conquer the Islands of Hawaiʻi, Maui Nui and Oʻahu by 1795 (defeating Kalanikūpule, Kahekili’s son) and ultimately ruled the island chain in 1810.)

Back on the continent, the discontent between the Colonists and the British Crown led to the American boycott of taxed British tea and the Boston Tea Party in 1773, and ultimately the American Revolutionary War (1775–1783) and then the War of 1812.