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Posted: November 29, 2012 11:01 p.m.

How much water do we have?

As county officials continue to await the government permits needed to begin work on the proposed Bear Creek Reservoir, they're taking steps to prepare the site in southeast Newton County for construction.

However, some residents and officials continue to question whether the reservoir will be needed any time soon - with confusion stemming from newly released numbers about how much usable water the county currently has - and how much the county's need for water will increase in future years.

We have water, but how much?
Newton County currently has two water-drinking reservoirs. The primary reservoir is Lake Varner; the actual water treatment plant for Lake Varner is called the Cornish Creek plant. City Pond is a much older and smaller reservoir; the actual water treatment plant for City Pond called the Williams Street plant. Both reservoirs can be supplied with water pumped out of the Alcovy River.

Right now, the Cornish Creek plant can produce a maximum of 25 million gallons per day (MGD). That's the amount of water that could physically be pushed through the treatment plant and out to customers in one day, according to the county's Water Resources Director Jason Nord. The Williams Street plant can treat a maximum of 4 MGD.

So, basically, if needed, the county could produce a maximum of 29 MGD of treated water in one day.

However, just because the county can pump that much water on any given day that doesn't mean that the county could pump that much water day after day for a long period of time. That latter number is called the maximum sustainable yield.

Originally, the maximum sustainable yield for Lake Varner was calculated at 24 MGD, according to Jim Mathis, a water resources engineer who did that yield analysis and worked on Newton County's water projects, including both Lake Varner and Bear Creek, for several years.

However, the 24 MGD number was based on the best data available at the time. Lake Varner was built in the early 1990s, and, at the time, Mathis and the state only had drought information from the 1980s.

Well, the droughts in the 1990s were worse, and the subsequent droughts of the 2000s were even worse, Nord said, which has since led to more conservative estimates as to how much water can realistically be pulled from the lake without pumping it nearly dry.

Following the 2007-2008 drought, Mathis said he did a revised yield analysis for Lake Varner and found that the maximum sustainable yield should be 23 MGD, a number that Mathis said the state accepted and is currently being used.

However, Mathis did not do the latest yield analysis. County Attorney Tommy Craig hired other engineers, Schnabel Engineering, to do another yield analysis - perhaps based on even more recent drought conditions - which showed Lake Varner's maximum sustainable yield is between 20 MGD to 21 MGD.

Nord said that number was also based on actual operating experience at the plant.
"That's the best estimate we can get. There's no way to actually know, because there's so many variables. There's drought, there's rainfall, there's customer usage, there's just so many different things," Nord said.

Mathis said the more important number is the average monthly yield - the average amount of water that can be taken from the reservoir per day during any given month. This number for Lake Varner is currently 28 MGD and has been for a while, Mathis said.

In his recent presentation to the Newton County Board of Commissioners, Craig did not provide a revised estimate for the average monthly yield, but he said late Friday that the engineers who did the yield analysis believe that the monthly average yield should be considered to be the same number: 20-21 MGD.

"We're trying to eliminate risk (of running out of water)," Craig said Friday night.

Reservoirs crucial during droughts
In 2011, the average annual withdrawal was around 12.5 MGD per day, Nord said.
Despite that level of usage, the lake's level dropped by more than 12 feet, which is about 50 percent of the lake's capacity. The drop was the result of stubbornly low rainfall totals, an issue that's become all too common.

Lake Varner's water supply is supplemented by pumping water out of the Alcovy River into the lake; however, the county wasn't able to pump any water because the river's flow was too low, which is common during most summers. However, in 2011, the lack of rainfall persisted longer than normal, Nord said.

By law, under its permit, the county cannot pump water when the Alcovy River's flow drops below 22 cubic feet of water per second. Sometimes in the summer, which is this region's dry driest season, the flow will get down to four to five cubic feet per second even without pumping.

"It's more like a trickle than it is a river and that dictates to us when we can use the water," Nord said.

There are technologies that allow water to be pumped and treated directly from a river, which could represent significant cost savings over building extensive reservoirs and dams. However, even in a non-drought year, the Alcovy River would be unable to sustain sufficient flows to fulfill Newton County's water needs. That's the whole reason Lake Varner was built.

"The reservoir is working exactly like it was designed. It's to store your water for when you have plentiful rainfall and are able to fill it up for the times when you can't and don't have rainfall," Nord said.

The winter and early spring are generally when the rains return and the rivers are full, and the reservoirs can be filled back up. However, the worse drought conditions become the more strained the reservoir gets. Given the fact the reservoir got down to half of its approximately 4 billion gallon capacity at an average annual use of 12.5 MGD, Nord said there are reasons to be concerned about future water availability.

"If we get up around 20 MGD average, we're going to be struggling to keep this lake full, seriously struggling. We're at a point now where we've got to be planning for the future," he said.

Water use still growing
Though the question of when Newton County will begin to approach its current water capacity limit is hard to answer, Craig and Nord believe the county will need more water capacity in about a decade - which is about how long Bear Creek Reservoir would take to get up and running.

"This isn't going to happen tomorrow," Nord said of a new reservoir. "This is a 10 year process before we're ever able to drink a drop of water out of the new plant...minimum seven years (if it's rushed)."

During the housing boom, water use was growing by about 5 percent to 7 percent per year, Nord said. However, since the housing market collapsed, Nord said growth has dropped to around 1 percent to 2 percent per year. Though lower, Nord said that still means water demand is growing, and both he and Craig noted that growth doesn't account for the arrival of more large industries, which tend to be huge water users.

"We're not trying to pull one over on anyone for sure. We're trying to make sure we have a sustainable water source," Nord said.

Whether the Bear Creek Reservoir is needed in 10 years or 30-plus years is largely dependent on population growth, industry growth and water use trends, which are unpredictable in this current housing and economic climate.

The Newton County Board of Commissioners recently voted to accept a long-term, very low-interest, 21-year loan from the state to build the reservoir. The board also approved hiring Schnabel Engineering and paying them $1.9 million to design the earthen dam for the reservoir.

However, the dam design contract is contingent upon the county getting the government permits needed to actually begin construction.

In the meantime, county officials and others will try to keep an eye on a changing climate.
"In the next three to four years, if we get another bad drought that (yield) number could drop (further)," Nord said. "Or maybe we've had the worst one we've had in a while and that number could get better."

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