Recent rain may improve water storage problems

Marco Island's water situation still isn't good — but with the rain the area received from Tropical Storm Alberto, the supply could be on its way to recovery. Rain the island received before the storm was absorbed by the soil, said Jeff Poteet, wastewater treatment manager.

"The last bit of rain helped tremendously," Poteet said on June 7. "It increased the lake level a little bit ... as soon as we get a little bit more rain, the amount of water in the lakes will be more sufficient."

The constant drizzle the area received from Alberto, which came from feeder bands while the storm continued it's path to north Florida, undoubtedly helped bulk up the island's supply of surface water, said Bruce Weinstein, senior project manager for the utilities department. After a heavy rain event like this one, water usage usually drops dramatically, he continued, because less water is used for irrigation thanks to residents' rain gauge sensors on their sprinkler systems.

However, unless that water is captured at Marco Lakes, where the surface water is stored, the benefits can be short-lived, he said.

An unusually dry spring prompted city officials to draw from three reserve wells after Henderson Creek, which supplies half of the island's 12-million-gallon-per-day demand, dried up last month. The remaining six million gallons is supplied by the city's reverse osmosis plant using water from deep wells. Currently, the city is using about three million gallons per day from reserves, with the reserve osmosis plant supplying the remaining nine million gallons per day.

Of the 320 million gallons of reserve water that was stored underground during last year's rainy season, about 70 million gallons remain, Poteet said.

Early last month the supply hovered between 100 and 120 million gallons.

"One (well) is a little higher than the other two," he said.

"The water is staying very consistent, so we're not running into any problems yet."

During the summer when Henderson Creek has peak flow, excess water at Marco Lake — where the creek water is stored — is pumped underground into a brackish aquifer, creating a pocket of fresh water.

For each 10 gallons that is stored there, about 7.5 can be reclaimed and used as drinking water.

"The wells are basically a bubble, so we're depleting that bubble," Poteet said. "But we're not showing any signs that we're getting anywhere close to the wall of the bubble."

Currently, the city has no plans to enforce more restrictive water conservation measures on residents.

"We're kind of watching the condition of our water supply right now, and then—hopefully— by this weekend we're hoping for rain."

Since the public was notified about the water shortage, Poteet said city staff has not seen any reduction in usage.

Block rates, however, have decreased water usage in single-family residences by 6.83 percent since the plan was implemented in January. The rate schedule is divided into five tiers according to lot size, and residents are allotted a water budget at a pretty good price, said Finance Director Bill Harrison. However, the price goes up once those residents exceed their limit.

"It has been proven over and over again that the best way to affect human behavior is through the pocketbook," Harrison said. "And what we found very pleasantly is that the block rates are doing exactly what we wanted them to do, which is encourage water conservation." About 70 percent of the island's water is used for irrigation and residents are currently under restrictions to water their lawns only three times a week. Future restrictions could require that residents water only twice per week.