WASD developed a comprehensive water-use efficiency program, which, it says, will provide cumulative savings of 19.6 MGD over the next 20 years.

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In the next five years, Florida’s Miami-Dade County Water and Sewer Dept. (WASD) has $5 billion worth of capital projects planned for improving its system, and another $5 billion in projects to help eliminate its use of ocean outfalls. Devoting these resources to improving its drinking water supply is one way in which the WASD says it can show dedication to the area’s natural resources.

“We are focused on diversifying our water supply portfolio and have many projects planned to achieve this,” Deputy Director David Yoder says. “Eventually, we also plan to do a major overhaul of our collection system. We are really highlighting conservation in our communication with consumers – that is by far the least-costly way of improving our water supply.”

Currently, virtually all water used by South Florida residents, visitors and businesses comes from the Biscayne Aquifer. This system is located just below the area’s land; its greatest depth is 250 feet. The aquifer is made of porous rock with tiny cracks and holes; rainwater – commonly called groundwater or the water table – seeps in and fills the cracks and holes.

The water is generally clean due to the effects of natural filtration, WASD says. The area, however, is prone to days with one foot of rainfall or droughts that last for years, which contributes to the vulnerability of the region’s water supply.

In 2007, the South Florida Water Management District (SFWMD) awarded WASD with a 20-year Water Use Permit, which is a plan for meeting present and future water needs of the county while protecting natural resources. The county must also ensure there is not too much water, which can cause floods, drown crops and damage the environment.

Per the permit’s requirements, WASD must develop a number of alternative water supply sources and continue its water-use efficiency programs.

“The SFWMD is a sub-regional regulatory agency that issues consumptive use permits to all the local utilities,” Yoder says. “The permit helps us protect the natural system and ensure we have enough drinking water. Our natural sources are primarily the Everglades and Lake Okeechobee. Our regular water system is operating at capacity, so we definitely need alternative sources.”

Reclaiming Resources
WASD’s alternative sources fall into four categories – reclamation, conservation, replenishment of ground water, and the treatment of brackish water to meet demands. Reclamation projects will allow the department to use highly treated wastewater that is purified.  

In Miami-Dade County, this water will be treated using technology that is the national benchmark for achieving the highest quality of reclaimed water, WASD says. The department is required to reclaim 170 million gallons per day (MGD) of water.

The county department’s reclamation work includes:

• Irrigation projects – With a new plant estimated to be complete in 2011, some of the reclaimed water will be used to irrigate golf courses, landscapes and other large expanses that need continuous irrigation. WASD says using reclaimed water will reduce the demand and stress currently being placed on its Biscayne Aquifer.
• Groundwater replenishment – Referred to as “aquifer recharge,” this process involves introducing highly purified reclaimed water into the ground to augment the water supply in the Biscayne Aquifer, allowing for additional withdrawal and treatment for water supply. The department has two projects in this sector – its South District work will be finished in 2014 and work in the West District is estimated to be complete in 2020. 
• Biscayne Bay coastal wetlands rehydration – WASD plans to use reclaimed water to provide additional water supply to the coastal wetlands near Biscayne Bay. The department explains this will help maintain a freshwater balance and to enhance restoration efforts, as well as South Florida’s sustainability. This project is estimated for completion in 2021.
  

An Alternative Aquifier
The next category of projects involves using the Floridan Aquifer as an alternative water supply. WASD explains this aquifer is located much deeper underground than the Biscayne Aquifer – which has historically supplied all of Miami-Dade County’s drinking water – and is brackish or salty.

To ensure this water is fit for use, it will have to undergo a more expensive and time-consuming treatment process, WASD says. This includes the ongoing work of pumping water from the Floridan Aquifer and blending it with water from the Biscayne Aquifer.

Water from the Floridian Aquifer also will be treated at the Hialeah Reverse Osmosis plant, which is scheduled to be complete in 2011. WASD explains reverse osmosis is one of the most rigorous treatment processes available, similar to a screen door with microscopic openings. The salty Floridan

Aquifer water is pushed through this “screen” with enormous power and pressure, thus eliminating a high percentage of contaminants.

“We are designing a new reclaimed water facility to support two irrigation projects we are planning, and we’re designing a larger facility to reclaim wastewater for ground water replenishment purposes,” Yoder says.

“We also have three plants that we are currently working to improve. In some areas, we are installing ultraviolet disinfection systems to store fresh water during our wet season, allowing us to use it during our dry season.”

Promoting Efficiency
WASD developed a comprehensive water-use efficiency program, which, it says, will provide cumulative savings of 19.6 MGD over the next 20 years. 

The department is using the Environmental Protection Agency’s Conserve Florida program to realize savings through the implementation of best management practices, including incentives that promote high-efficiency technology for indoor and outdoor water use.

Efficient water use programs include:

• Rebates for high-efficiency toilets and clothes washing machines;
• Full retrofits for high-efficiency toilets and showerheads; 
• Evaluating the water efficiency of various landscaping and irrigation practices;
• A program to encourage environmentally friendly lodging facilities and restaurants; and
• The Water Education for Teachers (WET) program that takes place in city schools.
  

“These programs allow consumers to become more involved in the process,” Yoder says. “We have public service announcements to remind people that water is an important local resource. During our wet season, it rains so hard and so often that sometimes all you seem to see is water. As a result, people can take that resource for granted.”

The department says these actions could reduce residents’ water usage by half, enabling them to save money.

Additionally, it notes, a small leak can waste about 70 gallons a day. Through its water-loss-reduction program, WASD says it is expected to save 14.25 MGD over the next 20 years. The loss-reduction program includes:

• Improving leak detection;
• Comparative accuracy testing on wholesale customer supply meters;
• Evaluating automated meter reading with leak monitoring;
• Performing a system-wide water audit;
• Reducing unmetered supply; and
• Conducting field accuracy tests for selected commercial and industrial meters.
  

“We are demonstrating a commitment to meeting the future demands of our system and protecting our natural resources,” Yoder says. “People come to our area because of our natural resources, so they are very important to us.

“We care about our proximity to the ocean, and by 2025, we plan to have eliminated our use of ocean outfalls – we will reclaim and reuse 60 percent of the water going to the outfalls. We have $5 billion dedicated to projects for the outfall system, which, I think, shows our dedication to this issue.”