The Quality and Quantity of Water in Vero Beach

Floridan Aquifer explanation

SO MUCH HAS BEEN WRITTEN IN THE LOCAL MEDIA ABOUT WATER QUALITY IN THE INDIAN RIVER LAGOON, which extends 156 miles from the Ponce de Leon Inlet to Hobe Sound. Particularly in Vero Beach, the Lagoon presents a water quality concern because of the Indian River Narrows, a channel with an elevation of “0” feet and an average depth of three feet. Water inside the Narrows and water that flows into it is mostly stuck there with no inlet to the Atlantic Ocean.

While so much has been written about the Lagoon, not much has been written about the “potable” water supply for Vero Beach, particularly at a time when Indian River County is one of the fastest growing regions in the Nation. In an August 2010 publication by Deborah Ecker, sponsored in part by Audubon of Florida and the Pelican Island Audubon Society entitled Indian River County WATER Coming and Going, the population in Indian River County will increase “174%” between 2010 and 2030.

Potable water is water suitable for drinking or cooking. It may be naturally potable or need to be treated in order to be safe. People can’t survive without water more than a couple of days.

Just as not much has been written about potable water, not much has been written about “non-potable” water. Non-potable water is water not suitable for drinking or cooking. Under the Workplace Health and Safety Act 1995, non-potable water is a “substance” in which manufacturers; suppliers and end users have a responsibility for risk management.

Water in Vero Beach and Indian River County is a “hugely complicated issue,” according to David Cox, a preeminent Vero Beach authority on ecological solutions crucial to conservation and a sustainable ecosystem; but he says it all comes down to a simple understanding that “water comes in and water goes out. That’s the way water works.”

Where is the Water?

 Florida was underwater until perhaps 20 million years ago when it rose above sea level. During this time the Floridan Aquifer was created, now the largest, oldest and deepest aquifer in the Southeastern United States. It is primarily built on a porous pile of phosphate rock and limestone, consisting of millions of shells from sea creatures decayed to form what now underlies the State. These layers of rock and limestone contain groundwater, which prohibit the downward flow of water. The Floridan Aquifer ranges over 100,000 square miles and extends into parts of southern Alabama, Southeastern Georgia, and Southern South Carolina.

An aquifer is an area under the ground where there is water. Water coming into Vero Beach comes in from the Floridan Aquifer, one of the most productive aquifers in the world. There are two layers in the aquifer beneath the earth that provide Vero Beach and Indian River County with its water. The top layer is the “Superficial” aquifer, 50 – 80 feet deep. 200-300 below the Surficial aquifer, approximately 1,000 feet deep, is the “Upper Floridan” aquifer. The layer in between these two aquifers is mostly clay, somewhat restricting the flow of water, up and down. These two aquifers are recharged by Indian River Count’s abundant rainwater drizzling down through the layers.

The risk to receiving water from the top Surficial aquifer is that it is easily affected by human activities, such a pollution from fertilizers and pesticides. The risk to receiving water from the Upper Floridan aquifer is that when water is withdrawn from it, it creates an opening for saltwater to intrude. Saltwater intrusion into the Upper Floridan aquifer can also flow up into the Superficial aquifer.

The problem with saltwater intrusion is that it can lead to contamination of drinking water sources and other consequences such as salinization (build-up of water in soils), where salt builds up in the soil so plants can’t get water from it.

The impact of soil salinization has had a devastating effect in Iraq, due in large part to thousands of years of agricultural activity. In 2009, for the first time ever, saltwater reached the confluence of the Tigres and Euphrates rivers, devastating agriculture and crops. A 2009 United Nations Scientific Educational and Cultural Organization (UNESCO) report found that since 2005 inadequate supplies of potable caused 100,000 Iraqis to flee their native communities.

How the Water Comes in

 According to a 2010 Water Quality Report published by the Vero Beach Sewer and Water Department, Vero Beach water is withdrawn from 33 wells. “26 of these draw water from the surficial aquifer…and the remaining seven wells draw water from the deeper Floridan aquifer.” These wells are located in “well fields”.

A well field is the land surrounding multiple wells drilled into an underground water source (aquifer).  Water from Vero Beach wellfields is either 1) pumped up to the surface, or 2) sprays up into the air based on positive pressure below it. Water that sprays up from positive pressure, like an oil well, is a good sign of an abundance of water, but when pressure decreases you have pump it up. Some local wells that used to spray up now have to be pumped.

Once again, water withdrawn from the surficial aquifer system presents risks due to human activities and water withdrawn from Floridan aquifer presents risks due to the presence of salt.

To remedy these issues, in 1992 the city of Vero Beach constructed a water treatment plant, called a Reverse Osmosis Plant (ROS). Water from the plant, according to Deborah Ecker, referred to above, is supplied beyond city limits: “south on the barrier island to St. Lucie County, north to most of Indian River Shores and west to Dodgertown.”

According to Ms. Ecker, “two-thirds of the city’s water is pumped from the surficial aquifer and treated by a water softening process and aeration. It is then mixed with the one-third that comes from the Upper Floridan aquifer that has been treated by reverse osmosis, desalination treatment system.”

Reverse osmosis is one of the most advanced water treatment methods available, developed by the US Government to desalinate seawater. It consists of semipermeable membrane, a “molecular filter,” that restrains particles smaller than bacteria, virus and salt molecules from passing through the membrane. Although most of the water forced through the membrane is pure drinking water, it is estimated that 20 – 25% of the water is reject water, called brine, which is saturated or strongly impregnated with salt. This water is treated as industrial waste.

The way in which the city deals with the brine is to inject it 2,600 feet back into the ground, well below the Surficial aquifer, approximately 1,000 feet deep.

How the Water Goes Out

Obviously, Vero Beach residents use pure drinking water from the water treatment plant for drinking, cooking, showering, washing and other uses. Rejected water from the plant is injected 2,600 feet into the ground.

Other water going out is Storm water. Storm water is water that comes in as rain and goes out as runoff water. In Vero Beach, in particular, runoff water is significant because of the Ten Mile Ridge, with a maximum height of 35 feet, which runs along I95. All the precipitation that falls east of the Ridge flows east to lower areas.

As the water flows east from the Ten Mile Ridge, or as it flows into storm drains from rain in and around the city, it picks up and carries many materials that can contaminate ground water supplies, such as lawn, garden and cleaning chemicals, solvents, drips and drops of oil and grease, chlorinated components and even antibiotics. Everyone always needs new tires because they wear down. Where does that worn off rubber go?

Vero Beach has a network of over 225 miles of canals and ditches that lead into its three major canals, North, Main and South, which flow into the Indian River Lagoon. Together these three canals discharge million gallons of water into the Lagoon.  All the runoff east of the Ten Mile Ridge flows into canals and ditches and ultimately into these three major canals.

Florida House Bill 1205, Chapter 2006-343 approved by the Governor on June 6, 2006, authorized the Indian River Farms Water Control District (IRFWCD) to “maintain” these ditches and canals. It repairs them, inspects them and cleans them.

As an example, in 2013 IRFWCD removed 9,227 cubic yards of water lettuce from the three canals, amounting to 3,656 tons. This tonnage consisted of 26,614 pounds of Nitrogen and 2,464 pounds of Phosphorus. This equates to 6,807 50 pound bags of fertilizer containing 5% Nitrogen and 5% Phosphorous.

According to the Environmental Protection Agency, “too much nitrogen and phosphorus in the water causes algae to grow faster than ecosystems can handle. Significant increases in algae harm water quality, food, resources and habitats and decrease the oxygen that fish and other aquatic life need to survive.”

Further investigation will reveal if the water in the canals is actually cleaner than the water in the Indian River Lagoon itself.

Summary

 According to David Cox, we should be “optimistic” about issues confronting us having to do with the quantity and quality of water in Vero Beach and Indian River County. There are many smart qualified professionals working on all these issues, at the Federal, State, County and local levels. There is State of Florida, which implements US EPA regulations, the St. John’s River Water Management District, the Indian River Farms Water Control District, six local water districts within Indian River County, the Indian River County Utility Services and Public Works – Stormwater Division and the City of Vero Beach.

The challenge is the coordination of all the constructive efforts of these organizations.

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