Study of unaccounted water losses of the Molokai Public Utilities, Inc. Kaluakoi Resort Water System

Abstract

Molokai Public Utilities, Inc. (MPUI) owns and operates the private water system that supplies Kaluakoi Resort on West Molokai. In December 1986, MPUI applied to the State Public Utilities Commission (PUC) for an increase in its water rates. In the PUC's Decision and Order No. 9695 of March 1988 granting this request, MPUI was ordered to submit a report on unaccounted water losses in its system. At the request of Carlsmith, Wichman, Case, Mukai & Ichiki, the law firm representing MPUI, Belt Collins & Associates proposed to study the unaccounted water losses in stages. The intent of the first stage was to assemble all available flow data in an interpretable form to account for non-revenue uses such as filler backwashing, to provide estimates for identifiable losses such as reservoir evaporation, and, using these results, to compute the amount of unaccounted losses. If these losses were unacceptably high, then subsequent stages of study would be conducted. This subsequent effort would primarily consist of leak detection in specific sections of the system. The first stage of the study has been completed and is summarized in this report. The period studied is from September 1985 to July 1988. Although the total of non-revenue uses and losses in the system is relatively high (from 24 to 28 percent over the last two and one-half years), most of this can be accounted for in the surplus well pumpage required for transmission through the State's Molokai Irrigation System (MIS) and filler backwashing. Based on the figures available, unaccounted losses in the system are less than five percent. This loss rate is considered to be acceptably low. In our opinion, the subsequent leak detection stages of the study are not warranted. It will be clear in reviewing the data. In this report that better coordination of meter reading and more timely compilation of these records is needed so the operators would have a current appraisal of the system's performance. These and other recommendations are presented at the end of the report.