The Inverness Public Utility District declared a water shortage emergency last week amid one of the driest years in the past century, and is already seeing its supply bounce back. “People have cut back [on usage], and we are holding steady for the time being,” said Wade Holland, the customer services manager for the district. “But we did declare. The availability will continue to decrease. The hot weather will come back. Consumption could increase.” The district has declared a shortage several times over the past four decades, and most recently in 2014. This year, 23 inches of rain fell in Inverness from October through June, compared to the nearly 38-inch average since 1925. Just five other years rivaled this year’s low rain levels over the past century, with an all-time annual low in the mid-70s at 18 inches. Even the drought years from 2012 to 2015 saw around five to 10 inches more rain each year than fell last year. Last week’s emergency declaration outlined four stages, the first of which is in effect. Under its terms, customers are prohibited from using water for construction without a special permit, for installing new landscaping, for drinking at restaurants except upon request, or, in most cases, for filling pools, ponds or private water tanks greater than 100 gallons. Hoses need a shut-off mechanism, and washing the exterior of buildings, sidewalks, driveways, patios and parking lots is not allowed. The second stage, which administrator Shelley Redding could implement as she sees fit, prohibits washing vehicles and places heavy restrictions on outdoor watering. The third stage bans outdoor watering altogether. Only the board of directors can declare the last and most severe stage, which involves rationing. Mr. Holland said one primary indicator determines whether increased regulations are necessary: water levels in storage tanks. The district’s distribution system does not have significant storage capacity but does employ tanks to hold the water pulled from the creeks and streams that run off the Inverness Ridge; those tanks turn over the water they contain every three days. Generally, the tanks draw down a portion each day and refill overnight. Lately, the water in the tanks was not rebounding, though since the district renewed its education effort two weeks ago, that has changed: The tanks are looking full again each morning. Mr. Holland believes some customers have voluntarily shut off nighttime irrigation systems, and that the cooler weather has helped.