WAILUKU — Scattered and isolated showers carried on the tail end of a shear line last weekend helped to dampen water use over the past week, according to water department records.
But mostly clear, if voggy, and dry conditions cut flows in the watersheds sharply while consumption in the Upcountry region eased higher to just over 6 million gallons a day for the period ended Wednesday.
Water Director Jeff Eng continued to caution Central and South Maui consumers to be conservative in their use of water, although demand over the past week remained low at 22.59 mgd — possibly helped by a day of soaking from 0.86 inch rain in Kihei, recorded between Feb. 24 and 25.
Eng said he believed the rainfall in South Maui could have cut use even lower, closer to the 20.28 mgd average demand recorded at the beginning of February.
“Despite the band of rain we received last Sunday and Monday, water production demand was relatively stable from the previous week,” he said.
“For our Central Maui customers, particularly those in South Maui, we ask them to be mindful of their outdoor watering.”
The Upcountry system was an even greater concern after three weeks of virtually no rainfall in the East Maui watershed. Since Feb. 10, the West Wailua Iki rain gauge in the East Maui watershed has recorded just over an inch of rain, and the water flow out of the area reflects the situation.
The Wailoa Ditch has been steadily falling and was flowing at 53.4 million gallons a day Friday, a quarter of its capacity. Storage in the water department’s Upcountry reservoirs also is continuing to fall, to 130 million gallons Friday after peaking at 175 million gallons Feb. 1.
“With the lack of rain in the East Maui watershed, we are closely monitoring the Upcountry reservoirs and ditch levels,” Eng said.
According to National Weather Service daily rainfall logs, the key East Maui gauge at West Wailua Iki recorded rain on just three days since Feb. 20, totaling a scant 12/100ths of an inch.
Over the same 10-day stretch, Puu Kukui in the West Maui watershed recorded just one day of rain, although that was a healthy 0.93 inch on Feb. 25. The farming region in Kula has been similarly dry, with one day of rain, Feb. 25, amounting to 0.32 inch.
The weather service forecast is for more of the same over the next week, with a high-pressure ridge again sliding over the islands to promote light winds and dry, clear days — with the possibility of increased vog, volcanic haze from the continuing Kilauea eruption, spreading across the island chain when trade winds falter.
With only light winds Saturday, a weather service analysis said there was a vog buildup off the Big Island that could flow over the other islands through the early part of the week.
