Lee County funds $1 million wastewater storage, recovery well study

FORT MYERS – The county will be spending almost $1 million to study if it can build an underground wastewater storage and recovery well in Fort Myers Beach.

Storing treated wastewater during the rainy season, and pulling it back up for use as irrigation water over the winter dry season, would help the county cut its discharges to the Caloosahatchee River, said County Manager Roger Desjarlais. Not only would it help customers in need of reclaimed water, like parks or golf courses, but could help the county cut down on the Caloosahatchee's already high nitrogen levels.

During the rainy season, the county usually disposes about 850 million gallons of treated water collected from sinks, showers, dishwashers and toilets, either through the deep injection well already in place at the Beach or pipes that dump into the Caloosahatchee. Storing and then reclaiming the wastewater during the dry season may cut the amount of nitrogen the county dumps into the river by as much as 2,840 pounds a year, county official say. But it would come at a steep price, said County Commission Chairman Frank Mann - about $6.9 million, according to county estimates.

The county already uses this kind of technology to store and withdraw drinking water deep under ground, but it has now hired a contractor, CH2M Hill Engineers Inc., to decide if the aquifers under the Beach are suitable to do the same thing with treated wastewater from the Fort Myers Beach and Fiesta Village treatment plants. Lee has not used this well technology for wastewater before, but other counties in Florida already do, said Patty DiPiero from Lee County Utilities.

Lee stores about 300 million gallons of drinking water in these kind of deep storage and withdrawal wells, DiPiero said. The fresh water pumped into the aquifer pushes the salty water out, and the salty water forms a kind of bubble around the fresh that, along with the layer of confining rock usually found in such aquifers, keeps most of the fresh water in place, DiPiero said. For the drinking water wells, the county usually recovers about 80 percent of what it stores.

In addition to reducing the county's nitrogen discharge into the river, the county also estimates it could earn about $96,250 a year selling the reclaimed wastewater to the golf courses and residential communities that rely on it to keep their landscaping alive during dry winters, DiPiero said. It would also conserve about 250 million gallons a year of groundwater that does not have to be used for irrigation, she said.

This kind of technology used to be at the heart of the water storage plans for the Everglades restoration project, but was rejected after project officials decided it wouldn't work there. Excess water could be stored in these wells, but not withdrawn. But county officials say that it has worked fine for potable water storage and recovery in Lee County since first launched in 2000.