IRRIGATION IN THE HAWAIIAN ISLANDS. 



BY GEO. MANSON. 



HOW many people are aware that fully one-half 

 of the sugar crop of the Hawaiian Islands, or 

 say about 60,000 tons per annum, is raised by 

 means of irrigation ? And yet it is a fact that were 

 it not for pipe lines, artesian wells, vast irrigation 

 ditches and various other appliances for the trans- 

 mission of water, including pumping machines of the 

 most extensive and expensive kinds, Hawaii would 

 not make the showing in the world's product it does 

 now. And while it is true that the sugar crop in 

 these islands is constantly on the increase, it is 

 equally true that that increase is due solely to im- 

 proved appliances, both irrigation and milling all of 

 the available lands which derive their water supply 

 from natural sources alone, having already been 

 placed under cultivation. 



While the numerous rice and tare patches which 

 are scattered throughout these islands, and which 

 require to be almost continually under water, are 

 supplied from natural sources, each patch of an acre 

 or less being situated a few inches lower than the 

 one above, the water from some natural stream or 

 spring being allowed to filter slowly downwards from 

 one to the other, it is a very different matter with the 

 cultivation of sugar cane, which must be irrigated to 

 a certain degree, according to the age of the plant, 

 and no more. The water must not be allowed to stand 

 about the roots for any considerable time. Hence in 

 large sugar plantations a large and continuous sup- 

 ply of water is the first and most important desider- 

 atum, and to obtain this and be certain of it at all 

 seasons of the year is the great problem to be 

 solved in order to secure good crops of sugar, and 

 every means is adopted looking to that end. 



Principal among these is the storage of water in 

 reservoirs in the mountains, whence it is piped to the 

 plantations, sometimes for many miles, and distributed 

 as required. This is the plan adopted at Spreckels- 

 ville, the great sugar plantation on the island of 

 Maui, which is the largest on the islands, if not in the 

 world. It is owned by the Hawaiian Commercial 

 and Sugar Company, but its stock is entirely con- . 

 trolled by the Spreckels family. At Spreckelsville the 

 water used is conveyed through an immense ditch 

 twenty miles long, the ravines being crossed by iron 

 pipes supported by trestle work. Even this supply 

 was not enough, and Mr. Spreckels has recently had 

 completed a three-mile line of iron pipe 24 inches in 

 diameter, which taps another source of water, and 

 opens up 500 acres of new land for irrigation. It is 

 claimed by Mr. Spreckels that it cost him $750,000 to 

 put the necessary water on his cane lands. 



This system or irrigation is also adopted on many 

 of the plantations on the island of Hawaii, but the 

 rainfall being so much greater on that island, less 

 storage water is required, the cane lands being irri- 

 gated by means of ditches or flumes connected di- 

 rectly with some large spring or creek. The planta- 

 tions in the vicinity of Hilo are examples of this 

 mode of irrigation, the cheapest of all. 



Another means of irrigation, which is practiced 

 most largely on the island of Oahu where the rainfall 

 is less than on any other island in the group, is the 

 transferring of water from springs or creeks. situated 

 on low lands to higher ones, by means of pumping 

 machinery of the most extensive kinds. Where this 



is done it is usually in connection with artesian wells, 

 of which there are many in this island. 



The artesian belt of the island of Oahu, according 

 to an extract from the exhaustive report of Messrs. 

 Allardt and Schuyler, the well known civil engineers, 

 consists of a marginal rim around the island from sea 

 level back to an elevation of 21 to 24 feet above. In 

 and around the city of Honolulu water will flow at 

 the maximum height of 42 feet, and here the largest 

 and strongest wells are found. In the Ewa and 

 Pearl City districts, which are situated some ten 

 miles west of Honolulu, the limit of rise is 32 

 feet, and in the other districts on the north side of the 

 island it ranges from 21 to 26 feet. The average 

 depth of the many wells so far bored is about 500 

 feet, the greatest depth being at Honolulu. The 

 combined flow of a group of four of these wel\s has 

 been ascertained by careful measurement to be 10.68 

 cubic feet per second, equal to half the water supply 

 of San Francisco. Two of the smallest of these, ag- 

 gregating 4.1 cubic feet per second, are now made to 

 irrigate 100 acres of rice. On no other island of the 

 group has artesian water been found, and it would 

 seem that nature has thus compensated Oahu for its 

 deficient rainfall. Even the geological formation is 

 so different from that of any other region of the 

 world where artesian water is obtained by boring, 

 that no scientific man would have risked his reputa- 

 tion in predicting the possibility of securing flowing 

 wells by boring in the volcanic and coral formations 

 of this country before success had demonstrated the 

 fact. To Mr. James Campbell is due the credit of 

 having the boldness to try the experiment which re- 

 sulted in the first flowing well in these islands. This 

 well was bored ten years ago on the lower slopes of 

 Honolulu! ranch and a good flow obtained at 273 

 feet. This well flows as well to-day as when it was 

 first bored. 



All of the lands in the southwestern portion of this 

 island, with the exception of a few scattered home- 

 steads, are granted to the Oahu Railway and Land 

 Company, and on a 60-year lease. This company 

 was formed tor the purpose of circling the island 

 both ways from Honovliuli, but as yet only twelve 

 miles have been completed. Eighteen more have 

 been recently graded, the rails for which are now on 

 the way. 



Some four years ago the great Ewa Plantation 

 Company was formed, its stock being subscribed 

 mostly at home. This company leased 5,000 acres 

 from the railroad for a term of 50 years. The soil 

 was analyzed and found to contain every requisite for 

 sugar cane, and the water question was solved at 

 once by boring artesian wells. There are now 

 twenty of these on the plantation, each ten inches in 

 diamster, divided into three stations distributed as 

 follows : 



The main pumping station, has twelve wells within a 

 space of 150x100 feet. The water is taken direct from 

 the wells by two powerful Blake pumps, the first of 

 which throws 7,000,000 gallons of water to an elevation 

 of 108 feet daily, while the second 8,000,000 gallons to 

 a height of 160 feet every 24 hours. About one-third 

 of a mile from the main station are six wells with a 

 pumping plant of the capacity of 20,000,000 gallons 

 per day. At about the same distance in another direc- 



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