2G C. H. HITCHCOCK — GEOLOGY OF OAHU 



water, as at Makiki reservoir, contain water which rises 40 feet above the 

 Bealevel within the bore-hole and must be pumped to be utilized. 



3. The depths at which the water has been reached average about 500 

 feet, but are very variable, and I have not .yet discovered whether there 

 is any law determining the position of tli is level. The deepest well, that 

 of James Campbell, at the seashore near Diamond head, was sunk 1,500 

 feet, but as no fresh water appeared, the boring was abandoned. The 

 water rose about a foot above the normal level in shallow wells, and was 

 briny as sea water itself. A similar case is mentioned at Waialua, where 

 very salt water only was found at a greater distance from the ocean. 

 Quite near to it, however, another boring furnished fresh water. Not 

 very far away from the James Campbell well, at Waikiki, another boring 

 proved successful at the depth of 820 feet. Within half a mile easterly 

 from the High School water was found at 420, 616, and 509 feet; toward 

 the sea, southerly, a less distance, at 762 feet, and a couple of blocks 

 westerly, 762 feet. About Punahou, 8 wells range from 213 to 370 feet. 

 In the Ewa district the range is from 273 to 692 feet; at Waialua from 

 200 to 590; in Koolau from 300 to 400 feet. A well at Waikiki, tested 

 by W. E. Rowell, superintendent of public works, proved to discharge 

 18 gallons to the second. At the largest pumping station on the Oahu 

 plantation 12 wells, each one foot in diameter, have been bored within 

 the limits of a building perhaps 60 feet square, and large engines are 

 constantly pumping water from them with no sign of exhaustion. 



4. Copious springs of fresh water are found at various places around 

 the island within tbe same artesian zone of elevation, as the Kamahe- 

 maha spring, beyond Punahou, near the railway station Honolulu, near 

 the railroad in Waialua, etcetera; hence it would appear that the fresh 

 water is disposed to discharge itself near the seashore wherever possible ; 

 also that it is the pressure of the sea water that causes the artesian liquid 

 to flow up to the level of 42 feet; or perhaps it would be better to say 

 that the ocean is a species of dam, causing the surplus water to discharge 

 wherever any outlet can be found, up to the 42-foot level. Professor J. 

 Le Conte says that fresh water rises in the midst of the ocean off the 

 Hawaiian islands.* Such streams must have been akin to those that 

 make tbe springs near the seashore. In this connection it is interesting 

 to ascertain whether the brine of the sea affects the quality of the arte- 

 sian water by its contact. As this is an important practical question, 

 various analyses have been made, both at tbe sugar plantations and at 

 the reservoirs containing potable water for domestic uses. It has been 

 found that there is a certain amount of chlorine in tbe water of those 

 w r ells nearest the sea, but that it diminishes inland. At Ewa plantation 



* Elements of Geology, p. 74. 



