The Peace River Manasota Regional Water Supply Authority is an independent special district created in 1982 as a water-planning organization in southwest Florida. But the organization’s mission changed in 1991 after a utilities development company in the region went bankrupt. 

The authority acquired the failed company’s infrastructure, including a water treatment plant, river intake pump station, a half-billion-gallon reservoir and 7 miles of 36-inch pipeline. Just like that, the authority became a water wholesaler to member-customers in Charlotte, DeSoto, Manatee and Sarasota counties. 

Three decades later, the authority has vastly expanded its operation and meets some 40% of potable water demands in a four-county area with a population of more than a million people. Two of the top 10 best-selling master-planned communities in Florida are in the mix. 

“Our job is to meet the demands of this growing population,” says Mike Coates, the authority’s executive director. All evidence suggests the water supplier is succeeding at the task.

Safe storage

The authority pulls its water from the Peace River, a peaceful stream that ambles southwest through wetlands and forests for more than a hundred miles before emptying into Charlotte Harbor on the Gulf side of the Florida peninsula. As in other area rivers, the water is discolored from decaying vegetation, yet is deemed to be of excellent quality. The water is drawn from the river in DeSoto County where the treatment plant is located. 

Built in the 1970s, the original 12 mgd treatment plant complex was expanded in 2000 and again in 2010. It now can process 51 mgd, which is comfortably above current 30 mgd customer demand. The technology of the plant has, of course, been upgraded through the years as well, utilizing redundant treatment trains to filter and enhance water. 

Four times in the last seven years, the Florida chapter of the American Water Works Association has declared it the “most outstanding” plant in the state.

The authority’s storage capacity has kept pace with the treatment plant’s expansion. The reserve water is critical to the authority’s mission. Southwest Florida has wet and dry seasons, which impact the Peace River’s flow and the amount of water that can be withdrawn from it. 

“We are permitted by the state to pull from the river when it is above a minimum flow or level. In an average year, we can take about 5% of the total flow,” Coates says. Such withdrawals are allowed mostly during the rainy summer season when the flow reaches seasonal highs. The percentage drops to zero during drier winter months.

It follows that the authority withdraws the maximum allowable amount of water in season and stores it for later use. Consequently, the authority has built up a huge water storage capacity above and below ground — with yet more planned.

The oldest reservoir in the system dates to the 1980s. It covers 85 acres and can hold 500 million gallons of water. While that’s impressive, a second reservoir constructed in 2009 is in a whole other league: It covers 640 acres and can store 6 billion gallons of water. When the river level is high enough, up to 120 million gallons of river water is pumped into the larger reservoir. From there, it travels to the smaller reservoir, then into the plant for treatment and, finally, into aboveground storage tanks for eventual distribution to wholesale customers.

That’s just the beginning of the storage story. Some of the treated river water is diverted to the Floridian aquifers underlying the authority property. The underground limestone pools can hold 6.3 billion gallons, the largest subsurface water storage containment in the eastern United States. It is accessed through 21 wells. 

“The water going into the aquifer is already fully treated drinking water,” notes Coates. Nevertheless, the recovered water is sent through the treatment plant a second time to eliminate any residue from the subterranean limestone caverns.

While all this storage might seem plentiful, think again: The authority has determined that the region’s projected growth in population and water usage requires even more standby water. So, a third reservoir is in the planning stage — one that will hold a whopping 9 billion gallons. 

“I don’t know if it’s the last reservoir we’ll ever construct,” says the director, “but it’s the last one we can fit on the property we have.” The estimated cost of the planned reservoir is $351 million. Expansion of the plant to facilitate treatment of this extra stored water will cost another $153 million.

Most of the water in the new reservoir will come from the river, of course, augmented by already collected water stored underground. In all, another 18 mgd will be added to the supply system to meet rapidly growing water demands in the region.

Thinking long-term

All of this strategic sourcing, stockpiling and distribution of river water is from careful design. After all, The Peace River Manasota Regional Water Supply Authority began life as a planning agency. Cost and usage projections, envisioning of eventualities, long-range calculations — these are the stuff of life for authority planners.

They look 50 years into the future and evaluate water sources, the probable cost of developing new sources, patterns of population development in the four-county area, and any other relevant variables. Then they formulate a 20-year plan for addressing the future. From that they come up with a working master plan, which is updated every five years.

Terri Holcomb, the organization’s director of engineering, notes that planning goes beyond the needs of the existing customer base. “We try to look at the area holistically to identify what new demands are apt to develop in the region and then coordinate with water management districts to meet them.” 

Using that approach, planners concluded that additional demand for water will beset the system by 2030 and yet further expansion will be necessary by 2040.

The final test of the efficacy of a water system probably is dependable delivery of water. The penultimate test, however, is the cost of delivering it. Peace River Manasota Regional Water Supply Authority board members are committed to maintaining a fiscally sound organization that can provide “affordable water rates that are fair and equitable.”

The wholesale price of water from the authority to partnering communities is based on two factors: a base rate to cover debt service and other fixed costs and a utilization rate to cover costs of power and chemicals required to produce clean and safe water. The current authority rate is about $3.60 per thousand gallons of water, according to Coates.

Retail water rates in the region vary from municipality to municipality depending upon local funding issues.

Extending reach

Collected and stored water is of no use to partnering municipalities unless it is distributed. To that end, the authority has 80-plus miles of transmission lines ranging from 24 to 48 inches in diameter. With two pipeline extensions in the works, the distribution system infrastructure soon will top 100 miles. 

One of the extensions is a 13-mile line 42 inches in diameter to be laid mostly in Charlotte County so water can get to a developing area in the western part of the county. A 7-mile line of the same dimension will run further north in Sarasota County to meet the needs of that “bustling” area. Yet another line running from there into Manatee County is anticipated. 

Before the system is built out, authority planners expect to add 50 more miles of pipeline. “Our extensions are based on our customers’ identified needs,” Coates says. “That determines where we must deliver water and with what pressure it will be delivered.” 

Maintaining water pressure is a contractual obligation. Three pump stations now can push the water to the end of the pipe and additional stations will be added as needed.

Though the authority inherited some relatively old infrastructure, the network of pipes and pump stations is practically new compared to many municipalities with pipes still in the ground after a century of use. 

“A lot of our pipes are less than 25 years old,” says Richard Anderson, the authority’s deputy director. “In pipe age, that’s fairly young.”

To maintain the sprawling system, the authority relies on 11 people, including three mechanics, three electricians and three instrument techs. Their equipment is along the lines of backhoes and dump trucks. “We have a fantastic crew doing all the preventive and corrective maintenance,” Anderson says. When bigger jobs loom, contractors are called.

Contractors also do the landscaping and mowing on the property. The two existing reservoirs are surrounded by 85 acres of grass on flat land as well as on embankments 45 feet tall. The contractors cutting all that grass keep their eyes out for anomalies in the earthen structures they are trimming. Any unusually dry areas, animal burrows and wet spots are reported to authority staff. A wet spot could mean a leak, and a leak in a 6 billion-gallon aboveground reservoir could be catastrophic.

When Hurricane Ian blew through last year, the system was dealt more than $3 million in damage. “We’re still working on repairs,” says Ann Lee, senior manager of finance. “We can talk about lessons learned in a storm, but no matter how much planning you do, it never is enough.”

Anderson adds: “Things happen you never anticipate happening. With Ian, the city of North Port was the hardest hit. Their power and communications were completely down. We couldn’t even talk to them on the phone and you never can communicate enough in those situations.”

One of the benefits of the authority’s 80-mile loop of pipe is that it interconnects municipalities in the four member counties. While the transmission lines are reserved for water delivery, other connecting links in the system can be engineered for coordinated water deliveries in emergency situations — such as when hurricanes come ashore.

With annual rainfall averaging 55-60 inches, the four-county area could be considered a water-rich area. “We are on the lower end of a couple of rivers and the Gulf of Mexico is right there,” Coates says. “We have plenty of opportunities.”

But all that rain doesn’t fall liberally year-round, nor does the rainwater bubble up from the ground across the region ready to drink and be heated on the stove, to flush toilets and wash clothes, to moisten flower beds and feed industrial processes. Turning rainwater into always-available potable water is where the regional authority comes in.