100 

 DIMSIOX OF HYDROGRAPHY 



Honolulu, Alarch 12, 1915. 



Board of Commissioners of Agriculture and Forestry. 



Gentlemen : — The following report of operations of the Divi- 

 sion of Hvdrographv during February. 1915, is submitted: 



\\-liATHER COXDITIONS. 



Except for the period February 20 to 24, the rainfall for the 

 month was far below normal, and streams are again nearing mini- 

 mum flow. The water in Wahiawa and the upper Xuuanu reser- 

 voirs has reached a verv low stage. 



UTILIZATION IXVESTIGATIOXS. 



An investigation of ditch losses on the \\'aialua Agricultural 

 Co. plantation was completed, and measurements were made to 

 check the Venturi meter and weir maintained below Wahiawa 

 reservoir. The loss by seepage in one of the ditches of Kahuku 

 plantation was also checked. Copies of these reports are append- 

 ed hereto. 



PUNALUU WATER. 



Additional investigations made in the Punaluu valley on Oahu 

 lead to the conclusion that a minimum of about eight million gaf- 

 lons per day, and an average of about ten million gallons per 

 day, of excellent water may be obtained at the 800-foot level in 

 that valley, and may be diverted without interfering with existing 

 diversions in the lower valley. Attached hereto are copies of 

 letters to the Governor and H. K. L. Castle relative to the utiliza- 

 tion of this w^ater. 



A new stream measurement station was installed in coi)pera- 

 tion with the \\'aiahfilo \\'ater Co. on the W'aiahole stream at a 

 ])oint about one thousand feet below their power i)lant, which 

 will keep a continuous record of the amount of water developed 

 in the north end of the Waiahole tunnel. The water company 

 I)aid all costs of this .station except for the services of the engineer 

 in charge, who is paid from Federal funds. The outflow from 

 this end of the tunnel has dropi)ed from 32 million gallons per 

 dav f>n Tanuarv 22 to .'^O million gallons i)er day on March 4. 



I.IT.ISLATIOX. 



Several conferences have been held with other territorial offi- 

 cials relative to the investigation and conservation of Hawaii's 



