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ion_avenger
08-24-2009, 09:14 AM
http://www.thenewstribune.com/news/local/story/846443.html

Tacoma Water, by the end of the year, will recommend the installation of water treatment equipment and storage that could raise rates by as much as 20 percent over three or four years beginning in 2011.

This affects 160,000 residential customers in Tacoma, University Place and other parts of Pierce County, as well as businesses and cities on Tacoma’s system.

The utility is facing dual pressures. First, it must comply with a new federal rule to ensure the drinking water is safe from cryptosporidium, a parasite that’s been found only once in eight years in city water. The second is more complicated and involves the long-term health of water from the Green River, the source of most of Tacoma’s water.

The city has two options. The utility is leaning toward recommending installation of the costlier and more complex one: a filtration system, which the utility has initially estimated will cost $140 million and result in an estimated rate increase of 15 percent to 20 percent. The other option is UV light disinfection, which the utility estimates could cost $70 million and result in an estimated rate increase of 5 percent to 10 percent. Utility officials believe a filtration system is a better investment.

“Filtration, nationally, is the standard for treatment of surface water. We are exceptionally fortunate to have gotten to 2009 without the need to filter our water,” said John Kirner, Tacoma Water superintendent. “Right now we’re seeing some regulations that will require us to take some action, so it comes down to how much are you willing to pay, and how much risk are you willing to accept?”

The Public Utility Board will decide which system to install and how to manage rate increases.

“If money were not an issue, filtration would be the way to go,” said chairwoman Laura Fox. “But obviously because of the rate impact, there are other options we’re exploring.”

Fox said those options include variations of size and location for either filtration or UV that would target only drinking water, not the entire supply.

Kirner confirmed that the utility is exploring different sizes for each system, but on Aug. 5 he discounted the idea of targeting only drinking water.

“I hate to put a whole lot of hope into that one because I’d be very surprised if that proves feasible,” Kirner said. “To do that would be terribly expensive – more expensive than filtering the entire supply, I think.”

The utility built the so-called second supply pipeline, which opened in 2005, for $220 million – and the ability to put drinking water down one pipe and non-drinking water down another would require a similar effort, he said.

Still, the utility will take a look at the idea.

“We were requested by one of the major industries in town to look at this, and we will,” Kirner said.

That industry, Simpson Tacoma Kraft, makes industrial-use paper on the Tideflats and is the single largest user of Tacoma water.

Dave McEntee, Simpson vice president of operational services and external affairs, said Aug. 6 that the company was interested in reducing any potential rate increase by assessing whether industrial water could be separated from drinking water.

Beyond that, conservation would remain the company’s main focus.

“We lower our bill when we use less gallons,” McEntee said.

‘CRYPTO’ CAUTION

Green River water flows from high in the Cascade Mountains to the main water facility northeast of Enumclaw, where it is treated before being sent to customers.

It’s here that water is tested for things that aren’t safe to drink. The latest bug that’s gotten the attention of federal regulators is cryptosporidium, a single-celled organism that most commonly causes diarrhea. Both the parasite and the disease are known as “crypto.” Most people have symptoms for one to two weeks, but they can come and go for 30 days. And that’s in healthy people – people with weak immune systems can die.

“In the 1990s, there was a very large crypto outbreak in Milwaukee,” said Wendy Marshall, a scientist with the EPA’s office in Seattle. “It sickened 450,000 and, depending on how you count the numbers, 50 to 100 people died. Milwaukee was doing what they were supposed to be doing, but (federal) regulations weren’t as protective. We didn’t know.”

Since then, outbreaks of crypto have happened sporadically across the country, from Utah to New York to Texas.

Tacoma Water began testing for crypto soon after the Milwaukee outbreak. Eight years ago, the utility started using a standard test each month.

“We’ve detected one organism in that time, in eight years of monthly testing,” said Chris McMeen, utility water quality manager.

The water-treatment decision is about more than crypto, Kirner said. The crypto rule “is kind of the straw that breaks the camel’s back. As an unfiltered surface water supply, we’ve had some pretty strict and well-defined rules we have to operate under.”

TACOMA WATER’S WORRIES

The federal Safe Drinking Water Act, first enacted in 1974 and amended in 1986 and 1996, outlined what is and isn’t allowed to be in drinking water. Most utilities filter their water. But because Tacoma’s water comes from such a pristine setting – the mountains, absent runoff from development and agriculture and industry – it has been able to avoid filtration and follow those strict rules by treating the water with a few chemicals, including chlorine. Chlorine does not kill crypto.

But the EPA’s Surface Water Treatment Rule also states that unless a water supply can meet certain criteria, it must filter. Tacoma Water is concerned about three of the criteria.

• Source water fecal coliform limits: This is a measure of how much bacteria from warm-blooded animals is in the water before it’s treated. It’s intended to be an indicator of the health of the watershed. The utility takes daily samples and must maintain a six-month running average below a certain level. If more than 10 percent of the tests in a six month period – approximately 18 tests – are above that level, the water must be filtered. From January to July of this year, one sample has tested above the limit. But in August and September of last year, six samples were above the limit.

• Disinfection byproducts below specific levels: When the utility puts chlorine into the water to kill certain things, the chemical also reacts with organic material such as algae and leaves. This chemical reaction creates a disinfection byproduct, and two groups of those are regulated because they’re suspected carcinogens. The utility takes quarterly samples and must maintain an annual running average for the entire water system below a certain level, or it must filter the water.

The annual running average for both groups, most recently assessed for the second quarter of this year, is one-third to one-quarter of the maximum amounts allowed. While that seems low, in 2012 the utility will have to keep the levels of disinfection byproducts low at testing locations within the water system, not just as a system-wide average. And tests at some of the locations have levels of disinfection byproducts that are much closer to the limit.

• Turbidity limits: Turbidity is a measure of dirt in the water. The EPA puts limits on turbidity because dirt in the water shields some bacteria from the effects of chlorine, so water at a particularly turbid level may not be clean enough to drink. The Green River gets dirty during big winter storms. The utility manages that now by mixing river water with water from the wells in the North Fork of the Green River, so there are times when the water sent to customers is almost entirely from the wells instead of the river.

During the past few years, the strength and frequency of winter storms have starting to create temporary turbidity in the wells. For example, during the big storm in January of this year, customers received water that was completely well water, and it still had a level of turbidity that was higher than normal, though not high enough to be in violation of the rule.

To be continued.............

ion_avenger
08-24-2009, 09:15 AM
WEIGHING OPTIONS

Water utility officials laid out the options for members of the Tacoma City Council and the Public Utility Board in a study session last month. And on Aug. 6, they met with more than a dozen people representing major stakeholders in the decision, including people from neighborhood councils and businesses.

The crypto rule requires action by 2012. Water managers in Portland and New York have challenged the crypto rule in court and lost. The EPA also has rejected requests for variances on the rules. Tacoma Water’s managers believe moving ahead with some sort of treatment is the only viable option.

The utility could install a UV light disinfection system at a much lower cost. That would meet the regulation for crypto. But if the utility later runs afoul of the Surface Water Treatment Rule, it could be forced to install a filtration system anyway.

“That’s the tough trade-off that’s the public policy question,” Tacoma Water’s Kirner said. “There are some benefits to filtration.

“Because we have turbidity, we have to put in more chlorine at the front end in order to make sure it gets to the far-reaches of the system,” he said. “And if we’re putting in much cleaner water, we can put in less chlorine.”

“But now we look at the cost,” Kirner said. “Are things likely to tighten up in the future? Yeah. They haven’t gotten any easier. Are we likely to find another organism that is of concern? … Probably. People keep finding things that are problematic. Is it gonna be soon? I don’t know. This is the risk-evaluation thing.”

Two City Council members who heard the presentation seem resigned to the choice of filtration.

Tacoma doesn’t really have two options, said Jake Fey. “I don’t want to do something on the cheap and find out we need to do something else later. I want to do it right the first time.”

“There is a one-size fits all with this federal regulation,” said Mike Lonergan. “I’m troubled by the fact that it is required, but it is.

“Filtration is probably the direction we need to go,” Lonergan said, not because the public’s safety is at risk but because of the stringent federal regulations.

Lonergan said he has heard complaints from his constituents about chlorine in the water, so less of that would be a silver lining.

NO ALARMS YET

Kirner said he expects the public discussion to include ways to mitigate the installation cost of a treatment system, especially since ratepayers have seen increases recently to pay for covering the McMillan Reservoir. He and Fox both mentioned slowing the utility’s aggressive water main and pipe replacement, which is one of its most expensive and long-term projects.

“Pipes and mains in the system are in pretty darn good shape,” Kirner said. So holding off on that for a while, while paying for filtration, is a better option to Kirner than delaying short-term projects, like fire hydrant maintenance.

“How long can you back off on main replacement without creating real problems?” Kirner said. “I’m not sure, but I’m pretty confident it’s a number of years.

“We’ve been good, and we’ve been lucky,” Kirner said. “Because you never know when the pipe’s gonna break in your city and you’re gonna be the one with a car sinking into the street.”

During the Aug. 6 stakeholder meeting, Kirner said that at this early stage, no work had been done on how the rate increases would be phased in. He told the group that if he and McMeen, the water quality manager, believed a public health threat existed, they’d be raising a loud alarm. They aren’t, he said.

But McMeen warned against complacency about cryptosporidium.

“We don’t believe we have zero crypto in our water,” he said. “We believe we have low levels.”

Kathleen Cooper: 253-597-8546

kathleen.cooper@thenewstribune.com

WHAT’S NEXT

Utility officials have scheduled a stakeholder panel meeting for the end of August. In September, utility officials will meet with consultants from CH2MHill to get an update on project assessments. A third stakeholder meeting is planned for the end of September or the beginning of October, said Tacoma Water spokeswoman Sonja Hall. The utility will make a formal recommendation to the Public Utility Board in November or December, she said.

TWO OPTIONS FOR WATER

FILTRATION

How it works: Specific chemicals are added to the water supply that cause particles and harmful organisms to stick together, forming larger particles, which are captured in a 6-foot filter of sand and sand-like material.

Pluses: Meets cryptosporidium regulation; positions utility to meet future regulations; handles a wide range of water quality issues, including dirty water and yellow water; increases reliability of Green River supply.

Minuses: Expense

UV TREATMENT

How it works:

Disease-causing organisms are exposed to high levels of photon energy at particular wavelengths, which sterilizes the organisms’ reproductive DNA, making them unable to replicate and cause disease.

Pluses: Meets cryptosporidium regulation; has lowest initial capital and operational costs.

Minuses: Filtration might be required later; system is sensitive to power fluctuations; does not address presence of disinfection byproducts or dirty water.

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