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A glass half-empty 

Savannah's water supply is threatened by growth, industry

In a community surrounded by a network of  rivers and marshes that segue to the ocean — and where streets are prone to flooding after even a moderate rainstorm — it’s difficult to imagine having a problem with the water supply.

While north Georgia’s drought officially ended in June 2009 and was closely followed by widespread flooding in Atlanta, the state’s water problems are really only just beginning. The tri–state water wars between Georgia, Florida and Alabama have heated up like the environmental version of SEC gridiron rivalries.

Meanwhile, southeastern Georgia has developed unique water problems of its own — problems that are a lot closer to our garden hoses and kitchen sinks than most folks realize. Despite its geography, coastal Georgia will not be immune to these problems, and within a decade we could be a severe drought away from disaster.

It won’t be one issue, however, that potentially renders the water supply short of our growing demand. The problems that could compromise our water supply are as complex as the series of pipes and mains that deliver water to all the homes and businesses across the city.

It will be a series of issues, including saltwater intrusion, industrial pollution and politics.

It begins with saltwater intrusion

“It’s harder to convince people we’re running out of water when they’re surrounded by water,” explains Bob Scanlon, the City of Savannah’s Water Resources Director. “But we’re living all the time like there’s a drought because of saltwater intrusion.”

Saltwater intrusion, the introduction of saltwater into our underground freshwater supply, is not a new problem. In fact, it might be the first water problem — the problem from which all other water problems will grow.

It was initially recognized scientifically in the early 1960s, and by the end of that decade a cloud of saltwater was causing supply wells near Brunswick to be abandoned.

Intrusion is caused by the demand placed on the Floridan Aquifer, which is essentially a huge underground limestone cavern that gathers and contains freshwater runoff from further inland. The Floridan Aquifer supplies tens of millions of gallons of very cheap, very clean groundwater per day to households and local industry alike across the Southeastern U.S.

But the water levels in the Floridan Aquifer have been reduced faster than they could be naturally replenished, creating pressure that pulls saltwater from the surface down into those limestone chambers.

There’s a second plume of saltwater in the aquifer under the northern end of Hilton Head Island that has also rendered numerous wells, including several belonging to the Hilton Head Public Service District, unusable. Although it’s dozens of miles away, the saltwater beneath Hilton Head is gradually moving toward Savannah because of ongoing pumping around the Savannah area.

South Carolina’s Department of Health and Environmental Control (DHEC), Georgia’s Environmental Protection Division (EPD) and several other agencies are currently studying what the effects of a third intrusion point off the shore of Tybee Island might also mean for the future of the Floridan Aquifer as a source of clean, reliable drinking water.

“Is saltwater coming through the confining unit into the aquifer at these points around the island? The answer is yes,” says David Blaize, a Division Director of DHEC’s Water Bureau. “The second question, and the one we’re working on now is, what does that mean?”

The new intrusion point was discovered in 2005 during analysis of the environmental impact of the proposed deepening of the Savannah River channel. The intrusion itself is unrelated to the potential deepening, however, and is a consequence of the depression created by pumping water out of the aquifer.

Additional analysis is pending, and Blaize says the hope is to have a report with a better understanding of the problem ready in a couple of months.

Most scientific models projected that the saltwater under the northern end of Hilton Head would take around 100 years to reach Savannah. But “there’s evidence that the saltwater intrusion in the Bluffton area was moving considerably faster than what was being predicted,” says Scanlon.

That potential third plume, considerably closer to the City of Savannah’s supply wells, could completely change the outlook for the Floridan Aquifer, and our ability to pull safe drinking water from it.

Life in the ‘Red Zone’

With the long term security of our aquifer in question, changes are underway to help slow the potential impacts, and on Jan. 1 of this year a series of mandates from Georgia’s EPD took effect to reduce the amount of water being pumped out of the aquifer.

The reductions to the groundwater permits, which are regulated by the EPD, were based on recommendations laid out in a June 2006 report titled “The Coastal Georgia Water and Wastewater Permitting Plan for Managing Salt Water Intrusion,” known simply as “The Plan” to those who work with it on a regular basis.

The area doing the most pumping — having the most effect on intrusion — and conversely seeing the least of its immediate effects was labeled in the Plan as the “Red Zone.” That area consists of Chatham and part of eastern Effingham counties.

All of the water systems pulling groundwater in the “Red Zone” were mandated to reduce their draws from the aquifer back to the levels documented in 2004 and then subtract another 5 million gallons per day (mgd).

According to EPD permits, the City of Savannah lost nearly 25 percent of its permitted average daily use, a reduction of 7.4 mgd from what had been allowed, and an actual reduction in use of more than 1.2 mgd (the City is permitted more than we actually use).

In comparison, International Paper had its permitted use reduced less than 10 percent, or about 1.2 mgd. Savannah and International Paper are by far the two largest groundwater users in the area.

The City has largely countered the loss of groundwater with highly effective, proactive conservation efforts, like the low flow toilet voucher program and discounted rain barrels.

“We’ve had a significant water conservation program in Savannah for 15 plus years,” Scanlon says. “We’ve seen reductions as high as 20 percent a household when they’ve switched to low flow toilets.”

To help balance demand and permit allowances, the City has also increased the amount of surface water blended into the drinking water supply.

Blending: Not just for Margaritas

Area residents have actually been drinking from the Savannah River for over a decade. In 1998, Savannah’s Industrial & Domestic water treatment plant came online with a potential total capacity of 62.5 mgd — enough to supply the City of Savannah, International Paper and most of the surrounding area with freshwater if need be.

Early on, it was conceived as water insurance for the future — savings for the opposite of a rainy day — a time when we no longer had the ability to quench our thirst from the aquifer. Recently, the City has begun using more surface water, so much that the Savannah Main system, which feeds faucets from the historic district to the southside, is now about a 50/50 blend of surface and groundwater. Parts of West Chatham are drinking surface water exclusively, according to Scanlon.

Though the concept of drinking water straight from the Savannah River may strike most of us as appalling at best, thanks to state–of–the–art treatment and monitoring systems, our surfacewater is not only safe, but tastefully tasteless as well. Savannah’s treated surfacewater has won taste tests at conventions held by the Georgia Association of Water Professionals.

There are drawbacks to drinking surfacewater, though, including cost and long–term safety of the water supply.

We might all be drinking nothing but surface water, except that the treated river water costs about three times as much per gallon as groundwater, which requires considerably less treatment thanks to natural filtration processes.

According to data provided by the Environmental Working Group, water utilities nationwide spend about 19 times more on water treatment chemicals than the federal government spends on protecting the average person from water pollution.

In the draft of this year’s City budget, the cost of using more surfacewater has been slowly absorbed by rate increases over the past few years. From 2007–09, cost of water increased between 6.4 and 7.7 percent. In 2010, that rate hike will slow to a 5.25 percent increase, and is projected to grow 5 percent in 2011.

It is, however, a necessary evil because conservation alone simply cannot save enough water to offset the mandated restrictions on groundwater while keeping up with the demand created by increasing population.

In the future, if we’re unable to use the Savannah River and need to develop additional surface water sources, it will cost even more. According to “The Plan,” a study by the Sound Science Initiative several years ago found that developing other surface water supplies will cost five times more than groundwater per gallon.

But is it possible that we wouldn’t be able to pull water safely from the Savannah River at all? Actually, yes.

Up the proverbial creek

The prevailing wisdom concerning water use along the Georgia side of the Savannah River has been to drink from the Floridan Aquifer and dump industrial waste into the river.

According to a report issued by Environment Georgia last year, the Savannah River was the fourth most toxic river in the United States. In 2007 alone, 7.6 million pounds of toxins were dumped into it.

While that’s hardly flattering, the numbers could be misleading according to some water professionals, because the toxicity is measured by volume of pollutants dumped into the river rather than the concentrations of those toxic chemicals in the water.

For example, although more than 19 tons of known cancer–causing agents were dumped into the Savannah River in 2007, because they were diluted into the billions of gallons of water that flow down the river every day, those discharges are less likely to have adverse effects on the average citizen’s health.

However, as demand for river water increases, it subsequently increases the concentrations of pollutants.

“The more waste water you put in, the more important it is to remain with a good high flow level,” explains Tonya Bonitatibus, executive director of the nonprofit advocacy group Savannah Riverkeeper. “For example, if the lakes are keeping water behind, then you don’t have a lot of water coming through, and what you end up with is a higher percentage of the pollution coming down.”

Demand for river flow will not decrease any time soon. Beyond the increasing water needs of the greater Savannah area, Beaufort and Jasper Counties in South Carolina pull about 20 mgd from the river. Other major consumers loom on the horizon as well.

One of the largest users on the river is Plant Vogtle, a Georgia Power nuclear facility. The plant requires large volumes of water to help cool its two reactors. In 2008, the plant drew an average 66.7 mgd, of which about two thirds was evaporated and the other third was returned to the river.

In non–drought conditions, Plant Vogtle currently uses about one percent of the average river flow.

In 2017, however, Vogtle’s third and fourth reactors are projected to come online, and the amount of water pulled from the river on a daily basis will double to about two percent of the average annual flow.

That reduction isn’t that significant if the river continues to flow at a normal level. But if we experience another drought similar to the one that ended last summer, it could spell disaster.

During the last drought, the river dropped below 30,000 cubic feet per second — average low flow — to 2500–3000 cubic feet per second. At these historically low rates, the pull from Plant Vogtle alone grows from two percent to somewhere between five and ten percent of the total river flow.

“I don’t think the Savannah River can afford to give up any water, because we’ve already got an impairment for dissolved oxygen in the lower part of the river,” says Scanlon. “If we reduce the flow, you’re gonna increase the concentration of waste loads.”

For a river that already has a dissolved oxygen impairment (oxygen-depleting substances are slowly asphyxiating the underwater habitat) and zero room left under its assimilative capacity (the amount of stuff that can be dumped into the river before it stops being able to naturally repair itself), that decrease in volume of water flow would have far–reaching impacts.

It could mean the destruction of natural habitat including, potentially, the harbor home of the endangered sturgeon. It could also render the river water undrinkable.

According to the Saltwater Management Plan: “Assimilative capacity in area streams will be strained...This will be particularly evident in the area of the Savannah Harbor... The amount of oxygen demanding substances in the waters being discharged to the Savannah River and its tributaries below Augusta is of great concern even under current conditions.”
Those dangers would be further compounded if Governor Sonny Perdue continues to entertain the notion of Inter–Basin Transfers (IBT) as a potential solution for metro Atlanta’s imminent water crisis.

Per the ruling of Judge Paul Magnuson in July 2009, Atlanta must stop using Lake Lanier as a water source by July 2012. Among the solutions on the table, Gov. Perdue has become oddly fixated with the concept of IBT, which is currently prohibited in the state. The idea is basically to pump water across the state from the Savannah River Basin to the Atlanta metro area.

The Water Contingency Planning Task Force, appointed by Perdue, released its findings in a Dec. 2009 report. They estimate the water needs of the Atlanta metro area without Lake Lanier to be about 250 mgd in 2012, which would blossom to 310 mgd by 2015, and 350 mgd by 2020. Early estimates show proactive conservation efforts could net about 80 mgd.

Even though IBT was noticeably absent from the task force’s short list of remedies, that didn’t stop Perdue from telling an audience assembled in Augusta last December that they needed to stop being so stingy with the Savannah River Basin’s water.

If IBT was approved, during low flow, Atlanta’s projected use would total 10-20 percent of the total flow.

“We use this thing as a toilet, we’ve got to continue to have the water to flush it,” says Bonitatibus.

Down the drain

The thing that may hurt us the most — or help, depending on your perspective — is that these issues aren’t going to affect the average person dramatically this week, or even this year. But without a doubt, the issue of where and how we get drinking water will continue to be one of the biggest issues in the state during this new decade.

Some issues — like the third saltwater intrusion point — may turn out to be less harmful than suspected after more complete studies. Or just the opposite could be true.

The same might be said about pollution in the Savannah River. Though the lower portion of the river is recognized as oxygen–impaired, the EPD — who helps regulate what gets dumped into the river, and by whom — is currently conducting studies to see whether it is possible to revise the Total Maximum Daily Load of pollutants (TMDL).

“We’re revising the TMDL, which had shown zero capacity available,” says Jeff Larson, EPD assistant branch chief for the Savannah and Ogeechee River Basins. “It will ultimately show what poundage is available, if any.”

The EPD is hoping to have the report done by May of this year, and will open possible changes up to public comment sometime before then.

While there aren’t a lot of clear answers right now, if we’re not careful — both as individuals willing to take responsibility for our own water use practices and collectively in the water policies we set for the future — we could end up sending a lot of bright plans for the future down the drain.

 

 

 

 

 

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Patrick Rodgers

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Connect Today 12.05.2016

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