The Department of Water Supply is asking Upcountry consumers to conserve water while Wailoa Ditch undergoes maintenance through tomorrow.

Without the ditch, the Pi'iholo Water Treatment Facility is the main source for Upcountry. The Pi'iholo facility also supplements the Olinda Water Treatment Facility.

The Wailoa Ditch has been providing 5 million gallons per day to the Kamole Treatment Facility in Hali'imaile. With Upcountry consumption exceeding 9 mgd, there is a risk the Pi'iholo and Olinda facilities won't be able to meet demand without conservation, said DWS spokeswoman Jacky Takakura.