Malcolm Pirnie's Scott Shannon and Food and Water Watch's Jorge Aguilar talk pros and cons
By Pat Hatfield
BEACON STAFF WRITER
posted Feb 25, 2010 - 3:17:30pm
The first phase of a study into building a seawater desalination plant on the Flagler County coast has just been completed.
Plans for the plant, called Coquina Coast, are in the very early phases. Pretty much the only thing set in stone is that the plant will be shore-based, not ship-based.
Earlier, the possibility of setting up a desalination plant on a ship had been the favorite. After study, a shore-based plant emerged as more dependable.
Now, preliminary design work is beginning. The engineering firm Malcolm Pirnie Inc. is in charge.
The St. Johns Water Management District will provide up to $2.2 million in funding and administrative services for the development of a detailed plan for a seawater desalination facility, and up to $14 million for construction.
The Water Management District estimates the extra water a desalination plant could provide will be needed by 2017. The District's Web page on Coquina Coast calls ocean water "drought proof."
Partners who have indicated interest in Coquina Coast are the Water Management District; Flagler, Marion and St. Johns counties; the Dunes Community Development District; and the cities of Palm Coast, DeLand, Mount Dora, Leesburg, Bunnell and Flagler Beach.
These water suppliers are looking at desalination as an alternative to drawing water from the St. Johns River. Conservation and other alternative sources are also being looked at, as the Water Management District pressures suppliers to draw less water from underground.
The Water Management District's position is that while conservation is needed and encouraged, not enough water can be saved to make up the future shortage.
The proposed Coquina Coast plant will use a reverse-osmosis system to purify the water. It's the most energy-efficient method, using much less energy than distillation, Malcolm-Pirnie engineer and senior associate Scott Shannon said.
First, water is run through a screen, to remove larger particles. Then, under enormous pressure, the water is forced through a membrane to remove salt and other dissolved matter.
Malcolm-Pirnie engineers came up with a conceptual picture of what can be built along the coast of either Flagler or St. Johns county. They envision a plant that will produce up to 25 million gallons of water a day (mgd) by about 2017, and up to 80 mgd by 2050.
Supply from other sources, such as reservoirs to capture rainwater, could reduce the future demand for desalinated water, Shannon said.
Plans for the plant are already under scrutiny and being criticized.
Jorge Aguilar is a spokesman for Food and Water Watch, a national consumer-advocacy group.
"We're very concerned, not only about food and water quality, but future supply," he told The Beacon.
Food and Water Watch, a nonprofit organization, has 6,000 followers in Florida, Aguilar said.
In January, the League of Women Voters of Volusia County invited Aquilar and Shannon of Malcolm-Pirnie to present pros and cons about the Flagler County plant in a public forum.
Key concerns are cost, the environment, and control of the plant.
Cost
Aguilar challenged the plan to finance Coquina Coast, as well as the estimated cost.
Malcolm-Pirnie projected that more than half the $1.3 billion cost of the completed plant, operating at 80 mgd, could come from state and federal grants. Sources such as the State Revolving Fund Program and the Water Resource Development Act have not funded projects at near the amounts Malcolm-Pirnie is counting on, and in some cases, don't fund this type of project, Aquilar said.
Shannon said Aguilar didn't factor in stimulus funds and other long-term funds.
"We're starting that effort right now, to identify and understand where those types of money will come from," Shannon said.
Aguilar believes Coquina Coast will cost about a third more than Malcolm-Pirnie estimates.
"I submit to you that these things never come in under cost," he said.
Shannon said cost estimates were put together based on the most recent data available, including figures from the recently constructed Gold Coast Desalination Plant in Australia. While plans are still in the conceptual stages, all contingencies possible were factored in.
There's been no lowballing, Shannon said.
The financing package and interest rate will affect the cost of desalinated water. Currently, the wholesale cost is estimated at $4.50 per 1,000 gallons — almost three times what DeLand residents currently pay. It's estimated that building a system to transmit the water to West Volusia would cost another 70 cents per 1,000 gallons.
Environmental
Aguilar said few details are available about the environmental effects of desalination plants.
Previous studies have indicated large marine organisms, such as adult fish, birds and mammals, may be killed on the intake screens. Smaller organisms can be killed during processing.
"The actual desalination process can cause subtle differences in marine communities over time," Aguilar cautioned. "These sort of environmental concerns usually get put at the back of the line."
Once salt is removed from water, it has to go somewhere. Usually, it is mixed back into the water source as briny waste.
The Florida Department of Environmental Protection (FDEP) has never permitted a coastal discharge of concentrated seawater, Aguilar said. The state classifies the discharge as industrial waste.
An engineer at the FDEP confirmed several permits from that department will be required for the plant, including one for industrial waste for the brine.
Shannon said intake baffles prevent organisms from being trapped on the intake screens.
The brine discharge, he said, while be 5 percent to 6 percent saline. The ocean water off the Flagler Coast contains about 3 percent saline. The brine will not be highly concentrated, and it will be diffused as it's discharged, reaching ocean salinity levels in a very short distance, Shannon said.
Aguilar also noted that the massive amount of electricity required to operate the plant will add more greenhouse gases to the atmosphere.
How much energy is that?
"For an initial stage of 25 million gallons per day capacity, the plant's energy consumption would be approximately 16 megawatts. At 80 million gallons per day, the consumption would be approximately 50 megawatts," Shannon said.
Progress-Energy Florida spokesman Tim Leljedal said a megawatt will provide enough power for 600 homes. So, 16 megawatts will power around 10,000 homes, and 50 megawatts would power 30,000 homes per day.
Shannon said alternate energy sources have not been ruled out. Florida Power and Light, provider of energy in the Coquina Coast area, is working with Malcolm-Pirnie to study options such as wind energy.
Ownership and control
Aguilar said private corporations that build plants and sell desalinated water to the public are leading the rush to build the plants.
Major and multinational corporations, like Malcolm-Pirnie, and plant constructors and operators Sinclair Knight Merz and Veolia Water make billions on desalination.
Not only that, ownership of plants like Coquina Coast creates a lot of potential for private interests to shape public policy and control water availability and price, Aguilar said.
It hasn't been determined who would own or operate Coquina Coast.
A ship-based facility likely would have been privately owned. With the land-based facility the choice, ownership options could range from a fully privatized facility to a facility owned and operated by the utilities, or other options somewhere between the two.
Malcolm-Pirnie's Shannon said, regardless of who operates the plant, the Public Service Commission would regulate its rates. He said the ownership decision will be made by local utilities.
What are we getting into?
"The decision to go with Coquina Coast is a momentous one, a big one for a group that's just coming together," Aguilar said. "It's important that citizens pay close attention to what this may mean."
He advocated conserving water and improving the current infrastructure before making the big leap into desalination.
Shannon emphasized that design work on the plant is just beginning, and it will be the utilities and municipalities involved who make the final decision on the scope of the venture.
"Our job is to educate them on what they would be getting into on a project like this," Shannon said. "We're nowhere near being close to a decision what it will ultimately be."
— pat@beacononlinenews.com
Copyright © 2010 The West Volusia Beacon
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