jL, ’ ■ $r> * r - H. ^’v^a/va. ^Ajl&a Ks / ht.'S~ & Namah Promotion Committee By P£ Newton Scale of Mi/es ^Poll’ll k. “ROUND-THE-ISLAND" TRIP 90 MILES Auto route via Nuuanu Pali Features Enroute: Pali, ancient battle ground; uoral Gardens. Kaneohe, Bay, 12 miles; heeia. Federal Wireless Station: Kahaluu, Libby Pineapple Cannery; Hauula Hotel, Hauula, 32 miles; Laie, (Mormon Settlement and Temple) : Kahuku Sugar Plantation ; Marconi Wireless Station; Boys' Industrial School; Ruins Ancient Heeiau; (Temple) ; Waialua Sugar Plantation; Haleiwa Hotel, Waialua. 56 rmles, auto, via Pali ; 31 miles, auto, via Wahiawa ; 56 miles, rail, via Kaena Point; Schofield Barracks, (Army Post) ; Wahiawa Pineapple District; Wahiawa Hotel; Pearl Harbor Lochs (view of U. S. Naval Station and Fort Kamehameha Military Reservation) ; Oahu Sugar Plantation (at Waipahu) ; Honolulu Sugar Plantation, (at Aiea) ; Moanalua Gardens; Fort Shafter; Bishop Museum. ROUND-THE-ISLAND A Rail Trip on Oahu. Passing Pearl Harbor, and Honolulu, Oahu, Ewu and Waianao Sugar Plantations; Haleiwa Hotel and Kahuku (terminus) connecting with Koolau R. R. via Laio and Hauula (hotel) for Kahana (terminus). LOOPING OAHU BY MOTOR History, poetry, legend and romance have woven a spell about a fairy-land that awaits the trav- eler in an all-day journey around the island of The pleasure of hours spent amid beautiful and* suggestive surroundings lies largely in the fact that impressions are not crowded, the mind mirrors clearly, shnrply, definitely, things seen and felt. In touring Oahu by motor or rail knows none of the mental and physical weariness which dulls at the end of a journey, the full appreciation of tho benefits received. About eight hours is taken in circling a pic- turesque portion of the island. Leaving Hono- lulu via the verdure-lined Nuuanu avenue, and up the valley, and passing tropical growths of riotous profusion, the matchless Pali six miles distant is reached, the traveler pausing to view of the oppo- site side of the island, a scene unrivaled where flies the Stars and Stripes. Here King Kameha- meha’s forces of historic fame in 1795 put to rout the Oahuans. Thousands met death at the bottom of n thousand-foot precipice. The awe-inspiring phases, the ever changing panorama of kaleidos- copic shades of lights and colors are unfolded while one descends 1200 feet by picturesque series of “switchback" and winding vistas of road into one of the most productive regions the island of Oahu boasts. Twelve miles from Honolulu, fish and all forms of marine life are seen under unique conditions where they take on unusual brilliance. Kaneohe coral gardens, a chief point of interest on wind- ward Oahu, is^easily accessible to the motorist. Kaneohe Bay where the depths of sea are^um folded as an open book. Wierdly fascinating are the formations, at times resembling the ruins of medieval castles, again looking like wonderfullv- branched forests or the verdure-lined streets of*a village. Through odd formations, scamper fish of every variety. Passing one of the biggest pineapple planta- tions and canneries in the Terirtory of Hawaii where the visitor is ever welcome, the plant of the Federal Wireless Telegraph Company, its tower- ing masts from which sound waves reaching to the American mainland, adds interest to the jour- ney. The motorist is rapidly whirled through Waiahole, outlet for one of the greatest engineer- ing feats west of the Rocky mountains, pictures- que Kahana valley, terminus of the railway sys- tem on the island of Oahu, and Haaula, where a stop can be made for meals. Here will be found a marvelous stretch of sand-carpeted beach, where bathing is superb, and as diversified as the color- ing of the water. The Sacred Falls two miles dis- tant afford a rare spectacle. The Church of Jesus Christ of Latter Day Saints (Mormon), more than a half century ago founded a thriving settlement at Laie which is on the route followed by round-the-island tour- ists. The largest Mormon temple west of Utah is now under construction here. Kahuku, a north- ermost point on Oahu offers inspection of a typi- cal sugar mill. The greatest radio plant in the world is in daily operation by the Marconi Tele- graph Company near this point. The territorial Industrial School for Boys is pointed out to the visitor as a model institution of this kind. Hale- iwa with its beautiful hotel, is a favored spot dear to the memory of a bather, surfer, golfer and lover of out-door life. It is filled with delight to the visitor fifty-two weeks in the year and has become famous as a rendezvous for game-fisnor- men. The hotel adds to the charm as a place for rest and recuperation. Before ascending to the great tableland on the homeward journey, cloud- saluting peaks confront the traveler. These moun- tains and their attractive foot-hills are the year- round clothed in gorgeous and abundant garb, supplied by nature. From Haleiwa, the route passes through abundant growth of sugar cane and pineapples. Schofield barracks, the largest military post west of the Rockies, lying at the base of Mt. Kaala, (4,040 feet) the highest peak on Oahu, is fast assuming pretentious proportions through the expenditure of millions of dollars by the United States government. At Pearl Harbor, with its beautiful expanse of land locked water. the location of the greatest naval station under the American flag, bursts into view. Honolulu and Diamond Head are seen in the distance. Aiea is a point of interest for visitors who would delve into the intricacies of sugar maknig and the process necessary to place it before the consumer. The “motor cruise” to Honolulu is con- tinued through a vast though charming retreat, the estate of Hon. Samuel M. Damon, Moanaiua Gardens are characteristic of “The Paradise of the Pacific” where meet and co-mingle the races from earth’s fartherest nooks and corners. A return to Honolclu, the gateway to what is destined to become the nation’s playground is made after a delightful journey of about 90 miles. The priceless delights of dbtdoor life in moun- fastness or along coral-fringed and verdure-clad seashore may be enjoyed to repletion within a few miles of Honolulu. The means of enjoyment are endless. Exploration for instance, is filled with surprising pleasures. Game fishing will be found unparalleled at Haleiwa and other points favored by the angler. Miles of rugged coast offer oppor- tunity to the camper. Well-defined trails lead from the belt road to vale and crag. An all-day tour of Oahu only leads to a desire for a better acquaintance of the island and a prolongation of a visit all too short. ANCIENT TEMPLES. The visitor is constantly reminded of the reli- gious rites followed by the ancient Hawaiian peo- ple by the presence of a number of well defined and preserved heeiaus (or temples), the ruins of which have proved a rich field for archeological T*\ research. One may be seen from an auto near Waimea Canyon. Chauffeurs will point it out Hotels and Boarding Houses Honolulu has a number of hotels which are equal in every way to the best first-class hotels on the mainland. They are conducted by Ameri- cans and are in every respect American. Their rates run from $1 per day up, European plan; and from $3 up, American plan. There are also a number of family hotels of the best class, besides boarding houses and lodging houses of varying standards. Their rates are approximately the same as in the average main- land city for similar service and accommodations furnished. Hack and Automobile Rates Rates of fare for passenger vehicles in Hono- lulu are limited by law. Hack fares about the city are based on a rate of 25 cents per mile per passenger, or fraction of each mile. Automobiles, $1.00 for one or two passengers. To Country Club, Moana Hotel or Kapiolani Park, single passengers, $1.00 each, additional 60 cents. Autos, $1.50, one or two passengers, and 50 cents each additional passenger. Continuous driving, single passenger, 50* each, additional 501 per hour. Automobiles, $4.00 per hour, 50c each over four passengers. Pali drive, one or two passengers, round trip, $5.00, each additional $1.00. Automobiles, $5.00 each additional passenger, over four, 50*. Punchbowl drive, one or two passengers, $3.00 each additional 60*. Automobiles, $4.00, 60* each over four passengers. Moanalua Polo Ground, one or two passengers, $5.00, each additional $1.00. Automobiles, $4.00, each additional 50 cents each. Round Diamond Head, one or two passengers, $4.00, each additional, $1.00. Automobiles, $4.00 50 cents each over four passengers. Round Island of Oahu by automobile, one to six passengers, $20.00 to $30.00, ($4.00 to $6.00 * p. m. and 6 a. m. - Children over five and not over ten years of age, half fare. Under five years, free. Engineering Features of the Waiahole Water Project of the Waiahole Water Co. Island of Oahu, Territory of Hawaii By Chas. H. Kluegel, Aem. Am. Soc. C.E. Honolulu The Hawaiian Gazette Co., Ltd. 1916 in tunnel, Waiawa Gulch. Digitized by the Internet Archive in 2017 with funding from University of Illinois Urbana-Champaign Alternates https://archive.org/details/engineeringfeatuOOklue Engineering Features of the Waiahole Water Project of the Waiahole Water Company. ISLAND OF OAHU, TERRITORY OF HAWAII By Chas. H. Kluegel, Mem. Am. Soc. C.E. The general plan or scheme of development adopted was that recommended by Mr. J. B. Lippincott, C.E., who made an . ex- haustive study of the project, going fully into the past history and study already made by Mr. J. Jorgensen and other parties, and reported to the Board of Directors of the Oahu Sugar Co., Ltd., under date of August 19, 1911. Mr. Lippincott was assisted in this work by Mr. W. A. Wall. During the following two years, the Waiahole Water Co., Ltd., was organized, and Mr. H. K. Bishop was appointed Chief En- gineer of the project in January, 1913, and the actual work of constructing the system began in February, 1913, the work being carried out directly by the Company under the direction of its Chief Engineer. This method of performing the work was followed until Octo- ber, 1913, when the remainder of the work, except the pipes across gulches, was let out to Mr. Jorgen Jorgensen, Contract Engineer. Mr. Bishop resigned as Chief Engineer at this time, and Mr. C. H. Kluegel was appointed Inspecting Engineer to complete the work. Later Mr. J. M. Young was appointed as Consulting Engineer. The work is thus divided into two stages. GENERAL PLAN The general plan provided for collecting the water from the many streams and gulches on the windward side of Oahu by means of tunnels through the ridges or spurs, and conveying the water, after collecting, through the mountain in the main tunnel to the leeward side of the Island, thence by tunnels, ditches and pipes, to the upper levels of Oahu Sugar Plantation. The tunnels connect up the various streams on the North side, and take in the water at the adits in the gulches. There are 27 of these tunnels on the North side, varying in length from 280 feet to 2332 feet, the aggregate length of the North side tunnels being 24,621 feet, or 4.66 miles, being in reality one continuous 6 tunnel. The number of adits at which water is taken in is 30, the intakes being located at the most advantageous points at the streams in the gulches. The maximum elevation at which water is taken into the tun- nel is 790 feet above sea level, and the grade or slope of the North side tunnels is 1.3 feet per thousand. The length of the main tunnel through the Koolau Ridge is 14,567 feet, or 2.76 miles, the grade or slope being 2.0 feet per thousand. The elevation of the North portal of the main tunnel is 752 feet above sea level, and at the South portal 724 feet. The length of the tunnels on the South side is 19,211 feet, or 3% miles, this distance comprising 14 tunnels, varying in length from 346 feet to 3329 feet. In these tunnels the slope or grade is somewhat less, being 1.3 feet per thousand, thus delivering the water at the lower end of the South side tunnels at an elevation of 699 feet. From this point the water is conveyed by means of cement-lined open ditches, elevated concrete ditches, four steel pipes, and three red- wood pipes. It is delivered to the upper boundary of Oahu plan- tation at an elevation of 650 feet through several distributaries, and by the main ditch, which reaches this elevation at the boun- dary of Honouliuli. The water is also delivered into numerous reservoirs, especially at night, when irrigating the cane fields is inconvenient. One of the larger reservoirs, on the line of the Waikakalaua storm water ditch, has long been in use. It is called Five Finger Reservoir. Its elevation was a determining factor in establishing the grade elevation of the Waiahole conduit. The length of open ditch between the last tunnel and the Wai- kakalaua gulch is 20,000 feet, or 3.79 miles. This portion of the waterway crosses three gulches, where riveted steel pipes are used, ditches being impracticable. The first of these pipes is 78 inches in diameter, and 1125 feet long, the maximum head being 165 feet. The second pipe is 78 inches in diameter, and 331 feet long, the maximum head being 80 feet. The third pipe, at Kipapa Gulch, is 72 inches in diam- eter, and 2034 feet long, and the maximum head is 270 feet. The fourth pipe crosses Waikakalaua Gulch. It is 72 inches in diam- eter and 970 feet long, the maximum head being 220 feet. This pipe crosses two tracks of the Oahu Railway, passing over one track and under the other. The aggregate length of the four steel pipes is 4460 feet to the West side of Waikakalaua Gulch. The pipes are made of steel plates varying from %" thickness for the highest heads to yy r thickness for the upper sections. The / pipes are riveted together in five and one-third-foot sections. They are supported on concrete piers of varying heights, de- pending on the topography of the ground, and the spacing of the piers is, in general, about 26 feet, the spacing being chosen in multiples of section length. The intakes and outlets of these pipes consist of a heavy con- struction of concrete, reinforced, and the intakes are provided with iron -grating bars to prevent the access of floating material of any kind, and as a safety precaution in case of a person or animal accidentally falling into the ditch near the pipe. 72-inch steel pipe across Waikakalaua Gulch, looking west. The pipes are provided with blow-off valves at the lowest points, and with man-holes for inspection, cleaning and painting, it being recognized that to keep steel pipes of this kind in good condition requires careful and thorough painting at frequent in- tervals. Provision is made by means of valves at the lowest point of the Kipapa Gulch pipe to take out water for irrigating the lands in Kipapa Gulch, and other lands lying below that level, and also for power purposes, should this latter become desirable at some 72-inch steel pipe across bottom of Kipapa Gulch. 9 future time; the water from the tail-race of the power plant being then available for irrigation after delivering up its power, the available hydraulic head at this point, being 280 feet. West of Waikakalaua Gulch, through Hoaeae and to the upper boundary of Oahu Plantation in Honouliuli, the conduit consists of 12,650 feet of cement-lined ditches, and three redwood pipes 5 feet in diameter, having an aggregate length of 2830 feet. SUBDIVISION OF WORK For convenience in administration, the project was subdivided as follows : North Division Tunnels. Main Tunnel South Division Tunnels South Division Ditch. . . Pipes Hoaeae Ditch Honouliuli Ditch Distributaries 24,621 ft. 4.66 miles 14,567 “ 2.76 “ 19,211 “ 3.64 “ 20,000 “ 3.79 “ 7,290 “ 1.38 “ 12,650 “ 2.40 “ approx. 2. approx. 6. Total 26.53 miles not including extensions by Oahu Sugar Co. ORGANIZATION When the work was undertaken, the time of completion was considered an important element, and Mr. Bishop’s organization was planned to secure the most expeditious execution of the project. The office of the Chief Engineer was located in Honolulu, where all plans were drawn, all maps were made, and records kept. The purchasing of material and the accounting were also done at the main office. The force in this office consisted of an Assistant Engineer, whose work was chiefly on plans and in pre- paring designs under the direction of the Chief Engineer ; draughtsmen, clerks, and stenographer. Reporting to the Chief Engineer were two Division Engineers — one located at each portal of the main tunnel, each Division Engineer having two parties in the field, each party consisting of a chief of party, transitman and rodman, and each division office had the services of a draughtsman for plotting up the notes and recording the data brought in by the field parties, all data being 10 sent in to the main office as soon as checked and worked up. Also reporting to the Chief Engineer was a General Superin- tendent of Construction, Mr. A. A. Wilson, who was in direct charge of all the constructing work. Reporting to the General Superintendent were two Assistant Superintendents, one located at each portal of the main tunnel, and each having in charge the tunnel foreman, the shift bosses, and the gangs of tunnel men. At the beginning of the tunnel work, three shifts of eight hours each were kept going. This was continued until the large amount of water coming into the tunnel, at North heading, became troublesome, and on account of the hardship on the men, working for eight hours in the cold water, it became necessary to cut the shifts down to six hours each, so that four shifts per day were employed for this heading. The temperature of the water in the tunnel was approximately 66° F., or about 8° colder than the artesian water in Honolulu, or, roughly, about 1° for each 100 feet of elevation. Great care was exercised in checking the surveys, the triangu- lations and the levels. This was given special care on the main tunnel, it being realized that while a small error in alignment would be unimportant, it would be necessary that all levels be correct. This levelling was done in the field by three separate parties, each of which went over the line twice, checking his own work, and the results of all three parties were checked against each other and found to compare within very small limits, thus eliminating any possibility of error. The instruments used for this work were thoroughly adjusted and tested for accuracy. The work on the main tunnel was started at once after the surveys were checked and found correct, and was done at first by hand in order to save time and push the work along as far as possible pending the arrival and installation of the air drills and machinery. It was of importance that bases of supplies be established at each portal, so all possible speed was made in constructing the railway from Waikane landing to the North portal and the rail' way from Pump 6 at Oahu Plantation to the South portal. In the meantime, camps were established and sanitary conve- niences were built to comply with the requirements of the Board of Health. No serious sickness, such as typhoid fever, gave any trouble. With the above organization, the surveys were made and checked, the plans prepared, the transportation line, consisting of six miles of track leading to the South portal from Pump 6, and three and a quarter miles of railway from Waikane landing to 11 the North portal, was built; camps were built; work was laid out in the field ; the power plants and machinery were installed, and the actual work of excavation and construction were well under way on October 1st, 1913, when this arrangement and organiza- tion was terminated. Gates at a section of finished conduit. The actual amount of main tunnel then driven was 912 feet on the North side and 2050 feet on the South side, or about 20% of the length of the main tunnel was driven under the direction of Mr. Bishop. Some work was also done on the lateral tunnels on both sides, but this part of the work was not rushed so much as the work on the main tunnel, inasmuch as the time required for the latter was the governing factor which controlled the date of completion. 12 INTERFERENCE BY WATER While it was suspected at the outset that considerable water might be encountered in the main bore through the mountain, it was not anticipated at the beginning that enough water would be developed to materially interfere with the progress of the excava- tion. This hope was not realized, however, for the main bore had proceeded only about 200 feet from the North portal when water to the extent of two million gallons daily was developed — this on breaking through the first dyke. These dykes are hard, impervious strata of rock lying approxi- mately at an angle of 45° to the tunnel axis, and nearly vertical, and they occur at intervals of varying length. Between the dykes was the porous water-bearing rock, thoroughly saturated, and with the water pent up between the dykes often under con- siderable pressure, so that when a dyke was penetrated, the water would spout out from the drill holes and would gush forth from the openings blasted in the headings. As the work progressed, the water increased in quantity and the difficulty of the work was enormously greater on account of the water. The slope of the tunnel being downward from the North por- tal, the matter of getting rid of the water by drainage was also one of great difficulty. This at first was managed by lowering the floor at the North portal about 2 feet, this being thought suffi- cient at that time, and allowing the water to drain out by gravity. At about 900 feet from the North portal, the flow of water having increased to 26 million gallons daily, the floor was again lowered to five feet below grade at the portal, and at this stage the men in the heading were working waist-deep in cold water, in a perfect torrent, the inflowing water coming principally from the face and from the roof and sides for a distance back from the heading, the flow of water apparently following the heading fairly closely. The pressure of water in the drill holes inter- fered very much with the blasting, so that the ordinary methods of charging and firing could not be used. The final expedient resorted to to hold the dynamite in place until it could be fired was to pack the sticks of explosive in thin metal tubes of the diameter of a stick of powder, and of sufficient length to enclose the quantity of powder desired. This scheme gave good results, but was expensive and materially delayed progress. The texture and hardness of the rock varied considerably — some of it being particularly soft and porous and much of it hard and flinty — particularly at the dykes. The dykes varied in thickness from 14 feet down to about 4 feet, but all the dykes were composed of very hard, close-grained rock which was ap- r 13 The Lord-Young Company’s wagon train hauling 72-inch pipe sections. 14 parently waterproof. All of the rock, however, was gritty and abrasive lava, and necessitated an unusual amount of drill sharp- ening, two of the latest type drill-sharpening machines being kept busy all the time. When the water had increased to the point where it could not be drained out by gravity by lowering the floor at the North portal, a siphon pipe made of redwood, and 16 inches in diam- eter, was installed, and this made it possible to drive the work ahead a short distance further. A second siphon pipe 20 inches in diameter was next installed at the side of the tunnel immedi- ately over the top of the 16-inch siphon, and this gave further relief and made it possible to extend the North heading to ap- proximately 1400 feet. At this point the maximum inflow of water was approximately 35 million gallons daily, which was taken out by the two siphons and gravity drainage. It was seen that the siphon method alone would not suffice for further drilling, so a relief or drainage tunnel was driven on the West side of and parallel to the main tunnel at a slightly higher level and on an ascending slope from the portal, its object being to intercept and drain off a portion of the troublesome in- flowing water. This tunnel was required to provide access at all times to the water register to be installed at the boundary between Waiahole and Waiawa, distant 1705 feet from the North portal. This expedient proved helpful after the tunnel was ex- tended in about 1400 feet. The two tunnels were then worked together alternately, first one and then the other, the floor of the main tunnel being kept above grade to avoid having the tunnel men work so deep in the water. They were working at this time in water about three feet deep. This alternate working was continued to 1700 feet from the North portal, where a chamber was blasted out of the solid rock on the side next to the relief tunnel. A cross-cut was made to connect the two, and a centrifugal pump of 13 million gallons capacity was installed, which raised the water of the main tunnel through a pipe to the relief tunnel, which, at this point, is some 18 feet higher, and the relief tunnel acted as a drain. With this arrangement, the work proceeded until the two head- ings met on December 13, 1915, and although the trouble and difficulty with the water never entirely ceased, it was possible to proceed slowly at an average rate of about 12 feet per day of 24 hours with three shifts. SOUTH HEADING, MAIN TUNNEL From the South portal the progress was rapid, often as high as 630 feet per month,, or about 21 feet per day on an average, 15 Water issuing from water-bearing rock in the main tunnel, 10,550 feet from the South j-oital. March 23, 1915. (The lanterns are held by men standing alongside a Leyner drill.) 16 notwithstanding the long haul, which at the last was over two miles. The first dyke on the South side was struck at 10,518 feet from the portal, the first evidence of water being from the drill holes, from which the water spouted under pressure. The measurements of pressure by gage on some of the plugged drill holes showed a pressure of 65 pounds per square inch, cor- responding to a static head of 150 feet. When water was struck, the excavation was discontinued temporarily. The spouting drill holes were plugged, the track was removed, and the floor of the tunnel, which up to this point was mainly through porous rock, was lined with concrete with a plastered cement surface ; the walls in the meantime having been lined and cemented to make them watertight. Such portions of the tunnel as required over- head arching had been arched and made ready for use. The track was then replaced and the work continued at re- duced speed, due to the water, which came in in large quanti- ties, the maximum flow from this heading reaching 17 million gallons daily, until the two headings met at 11,679 feet from the South portal. From the foregoing it will be seen that 80% of the length of the main tunnel was driven from the South portal, and 20% of the length was driven from the North portal, the difference in these proportions from the two headings being due to the pres- ence of water at a much earlier stage in the North heading. Had there been no water to contend with, the length driven from each heading would have been approximately the same. In order to give room for the water to flow from the heading, the track was raised on timbers of 4x12 in long lengths, placed edgewise as stringers, on top of which the track ties were laid. The track was 24" gage, laid with 16-pound and 20-pound T-rail. The cars used were the standard Koppel one-yard, all-steel dump cars. Electric locomotives driven by storage batteries were used in both headings. These gave good service on short hauls, except for the necessity of frequent recharging of the batteries, and minor difficulties due to water. A gasoline motor tractor was used for the long haul, until the track was raised in the South heading, the raising of the track leaving insufficient clearance for the gasoline locomotive. A cable haul was then installed, this operating entirely with- out interruption from the water and clearance. The steel cable used was one-half inch in diameter, and was approximately four miles in length, spliced to make a continuous cable, and running over a sheave secured to a timber in the floor of the tunnel at 10,800 feet from the South portal. The cable tractor was a 17 Portion of tunnel, showing forms for arch of tunnel roof. double-drum puller with a cable tightener, and was driven by belt and gearing from a 50 H. P. electric motor. There was considerable wear on the cable, due to abrasion on the ties. This wear was much reduced by damming up the water in the tunnel at frequent intervals in order to permit the cable to run in the water, which, apparently, acted as a lubricant and reduced the 18 wear. The cable parted on two occasions, and delayed the work until a splice could be made. One cable was completely worn out and the second cable used was probably about half worn out, over a period of eight months. POWER PLANT At the outset it was planned by Mr. Bishop to supply electric power to the two portals for operating the air compressors and other machinery from a central power station, located at Pump 6, transmitting at high voltage by pole line to the two portals, the pole line extending past the South portal over the mountain to the North portal. This station was installed and the power line was built from Pump 6 as stated, but before it was completed, water had been struck on the North side, and the quantity was found to be suf- ficient to supply all the power needed, the available convenient hydraulic head being approximately 250 feet. The central steam- driven power plant was completed, however, and held at reserve for emergency use, although the plant and power line from Pump 6 to the South portal was used very little. The central power plant consisted of 500 H. P. Babcock & Wilcox water-tube boilers, supplying steam at 180 lbs. pressure, to a 350 K.W. high-pressure non-condensing steam turbo generator set, delivering 3-phase current at 3300 volts pressure, stepped up and transmitted at 11,000 volts to the two stations at the portals, and there stepped down to 250 volts for use at the motors. Oil fuel was used for the boilers, and the location at Pump 6 was chiefly on account of the convenience of fuel supply, which was drawn from the tanks supplying fuel to the boilers at Pump 6. The plant which actually supplied the power for use at the tunnel was a 350 H. P. Pelton water-wheel belted to 300 K.W. 3-phase generator, these units being installed in the gulch below and near the North portal. There was an abundance of water from the North heading, and the head at the Pelton wheel was 250 feet. This made an inex- pensive and easily operated plant which was entirely satisfactory except at rare intervals when the water was low. The power was transmitted by pole line to the South portal in the opposite direction to that originally planned. The local plant at each portal contained a duplex 2-stage Inger- soll-Rand air compressor, supplying 800 cubic feet of free air per minute, at a pressure of 100 pounds per square inch, belted to electric motors ; receivers ; Leyner drills ; sharpening machine ; pumps ; blacksmithing equipment ; blowers for ventilation ; a num- 4 19 ber of small machine tools for repair work, and facilities for making up the metal powder tubes. The air drills used were the water-Leyner drills up to 10 feet long. These drills use a jet of water under pressure which forces out the cuttings from the point of the drill. They are capable of rapid drilling, there being very little interruption from the clogging up of cuttings. Air was supplied to the drills by a 4-inch pipe line running to a manifold which was always near the heading. Each round required from 12 to 20 holes, eight to ten feet depth, the holes being drilled at slightly converging angles in order to break the rock effectively. Each round required from 50 to 100 pounds of 40% or 60% dynamite, Giant brand being used. Steel pipes at Waikakalaua Gulch, crossing a branch of the Oahp Railway. The larger one is the new 72-inch pipe. The ventilation of the tunnel headings was secured by forcing air by means of blowers through 16-inch metal pipes which were carried along the side of the tunnel, the air being forced in con- tinuously. When a shot was fired, the direction of the blower * was reversed for a while, and the smoke and foul air was drawn 20 out of the tunnel through the pipe until it was clear and fit for the men to work. This arrangement of ventilation proved ef- fective and saved a great deal of time. LABOR Special tribute should be paid to the Japanese tunnel men, without whom the excellent progress made on the tunnel would have been impossible. These “professional” tunnel men, as they Japanese professional tunnel men, Main Tunnel, July, 1914. call themselves, prefer this work to any other, and they appar- ently take delight in the hardships incident to the work, the exposure to the cold water, and the risk in handling explosives. They were on the job all the time and never failed to deliver the goods in situations in which white men or native Hawaiians would have been physically impossible. Most of the drilling and mucking was done by these tunnel men as sub-contractors — a bonus being given for rapid work, which sharpened their interest and never failed to give results. CAPACITY OF CONDUIT The size of tunnel section is approximately 7 feet wide and 7 feet high, but in many places the section is larger, due to the uneven cleavage of the rock, and the fact that certain portions are unlined. The capacities of different portions of the conduit are as follows : 21 9 i Tunnels 18-27 North side 80 million gallons daily Tunnels 13-18 North side 100 do. Tunnels 1-13 North side 115 do. Main tunnel 150 do. Lateral tunnels South side 125 do. Pipes and ditches to Kipapa Gulch. . . .125 do. Pipe across Kipapa Gulch 100 do. Ditches beyond Kipapa Gulch 100, 140 and 40 do. Pipes beyond Kipapa Gulch. . . .100 and 40 do. 72 -inch steel pipe, Kipapa Gulch. The capacities of the various parts of the conduit are affected to a considerable extent by the slope or grade. The tunnel sec- tion was governed to a very large degree by the minimum size in which the most rapid work could be done, and in general the section for this reason is greater than the 7-feet size specified. MEASUREMENT OF WATER The main bore through the mountain was intended at the beginning to be merely a conduit to convey the water from one side to the other, but in the process of building the tunnel, water * 22 Location of water-measuring station between lateral tunnels H and I, Waiawa Gulch. t 23 was developed so that this became a source of supply, and for this reason it is necessary to measure the flow at certain boun- daries as a basis of payment for the water to the owners of the land. Two stations for the measurement of water are operated, one at the boundary of Waiahole and Waiawa, and one between lateral tunnels H and I on the South side, measurements at these points being all that are required for payment of the water. These stations are in channels of uniform sections which are rated, and the stage of water is recorded by an automatic water- stage register, thus giving a permanent record of the daily flow as a basis for payment. Open ditch in Waiawa, with cement lining. The maximum quantity of water developed was on October 16, 1914, and was approximately 35 million gallons daily from the North portal. The flow of water has varied considerably from time to time, and has been decreasing, apparently indicating that the water stored in the mountain between the dykes is grad- ually being drained off. It is thought that the permanent or con- tinual flow from the tunnel bore will be governed by the rainfall over this drainage area. The present flow of water percolating into the main tunnel is 14 million gallons daily. This appears to be the dry weather flow. CLOSED CONDUIT SYSTEM This system of tunnels is essentially a closed-conduit system — « that is, the flow is entirely through closed tunnels, not subject to 24 interruption by freshets or washouts or from rubbish or wash from the mountain streams, the intakes being so built as to admit only water as free from rubbish as practicable. Only at three points in the tunnel system — and these are on the South side, one of which is a gaging station — does the water flow in open chan- nels for an aggregate length of 160 feet. Pipes were not a part of the contract to Mr. Jorgen Jorgensen. Steel pipes were let out to contract to the Lord-Young Engineer- ing Co. The last of these pipes has just been completed. The contract for the redwood pipes was let to Lewers & Cooke, Ltd. It is intended to use the reservoirs so far as possible to take care of the water flowing at night, so as to utilize the conduit to its fullest capacity. The Waiahole Water Co. has taken over from the Oahu Sugar Co. the Ahrens Ditch in Waiawa, the Kipapa Ditch, the Wai- kakalaua Ditch in Waipio, and the Hoaeae Ditch. Two redwood pipes having total length of 1223 feet have been laid across two gulches on the line of Hoaeae Ditch, cutting out 2j| miles of ditch. The water delivered by the Waiahole System is chiefly used on newly-planted cane on land above the lift of the pumps. During construction the water developed in the main tunnel near the South portal was at times utilized for irrigation. On May 27, 1916, with Mr. H. Olstad as Superintendent, continuous oper- ation of the project was begun. 4