Alternative Water Supplies for Florida

To compensate for depleted groundwater, Florida is exploring new sources

For decades, Florida has been using up its freshwater resources, and analyses of water management districts show that there will soon be too little groundwater to accommodate present levels of usage. So the state's Office of Water Policy and Ecosystems Restoration has announced that Florida is developing alternative sources of water.

Until 1980, surface water accounted for most of Florida's use of fresh water. Then groundwater became the dominant source. Now, though, withdrawals of groundwater are expected to flatten as the supply dwindles. Without remedial action, the state is facing saline intrusion, lower spring flows, sinking lake levels, and loss of wetlands. That's why alternative sources of water, like brackish water as a source of drinking water, are now on the table.

Desalination of brackish water and seawater

Florida certainly has an abundance of seawater that can be desalinated. However, because of the lower saline levels involved, brackish water reverse osmosis (BWRO) desalination is significantly easier and less expensive than seawater reverse osmosis (SWRO) desalination. In fact, a BWRO plant in Texas will soon be able to produce drinking water from brackish water at a cost even lower than that of its current piped-in water source.

Florida is rich in brackish water. Already, the state has over 140 operational BWRO facilities, and there is plenty of opportunity for growth.

In the Tampa Bay area, Florida also boasts one of the largest SWRO plants in the country. Reverse osmosis requires energy-intensive pressurization to force the seawater through the advanced membranes that screen out salt. To keep the plants functioning, maintenance must be conducted without fail. Also, the hypersaline brine byproduct must be carefully disposed of to avoid damaging the environment.

Despite the stringent requirements, reverse osmosis is the most energy-efficient way to desalinate on a large scale.

Water reclamation

Also known as water recycling or water reuse, water reclamation is significantly less expensive than either form of reverse osmosis. Florida has an abundance of water sources that are ripe for reclamation, including stormwater, runoff, and treated municipal and industrial wastewater. Reclaiming these resources reduces the strain on traditional freshwater reserves.

When it comes to water reuse, it is important to ensure that the treated water meets the standards required for the intended applications. These may include irrigating farms and golf courses, flushing toilets, washing vehicles and pavements, and replenishing aquifers. Whether conventional sludge processes are used or innovative membrane bioreactor (MBR) technology, wastewater is transformed into a viable water source.

The fact that reclamation is cheaper than reverse osmosis isn't the only benefit. Reclaiming water also helps to conserve essential freshwater resources.

Aquifer storage and recovery

Florida is also exploring aquifer storage and recovery (ASR), an innovative approach that includes methods like groundwater banking and managed aquifer recharge (MAR).

Groundwater banking is a water management strategy that involves storing excess surface water or treated water in underground aquifers for later use. It uses natural geological formations as reservoirs to store water during times of plenty, such as wet periods. The stored water can then be recovered during times of scarcity or drought.

Managed aquifer recharge is a water management technique that involves directing water, often surface water, to underground aquifers to replenish ("recharge") them. MAR increases the amount of water stored in aquifers during times of plenty. As in the case of banked groundwater, the expanded aquifers can then be tapped when water is scarce.

During hurricanes and other severe rainfall events to which Florida is susceptible, it makes sense to capture and store the excess freshwater before it flows back into the ocean.

All of these methods of diversifying water sources and expanding storage make the water supply more dependable and resilient throughout the state.

Looking ahead

As we delve into these various avenues of water sourcing and management, we recognize the importance of fostering a multifaceted approach that integrates water conservation initiatives and public education. The challenges we face in securing Florida's water future are substantial, yet there exist economical methods to meet our future water demands. The realization is dawning that the era of abundant, easily accessible freshwater is a thing of the past. Nevertheless, through proactive measures like embracing water reclamation, harnessing brackish and seawater desalination, and implementing aquifer storage and recovery, Florida can navigate the complexities of water scarcity with a newfound sense of resilience and responsibility. By collectively steering towards sustainable water practices, we can ensure a more sustainable and vibrant future for the Sunshine State.