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City to move ahead with UV water treatment
By Terri Harber
Some Baker City Councilors still have questions, but on Tuesday the council didn’t object to the city continuing to work toward using ultraviolet light to protect drinking water from cryptosporidium and other parasites.
Until a treatment system is constructed and fully operating, residents will be sitting on “pins and needles,” said David Leland, the Oregon Health Authority’s interim director of the Center for Health Protection.
Leland assured the councilors that a UV treatment system is “still an option” that would comply with a 2006 federal rule requiring cities that don’t filter their water, such as Baker City, to add a treatment method that deals with crypto, which is resistant to the chlorine the city now adds to its water as a disinfectant.
Hundreds of residents, and possibly a thousand or more, likely were infected with crypto in the city’s water in July.
Residents were asked to boil water beginning July 31 until Aug. 20. The boil order ended after several water samples showed no evidence of crypto.
The city will continue to test water twice a week. The boil order will be reinstated if two consecutive tests contain any amount of crypto.
Leland said there are two keys to stopping future parasite infections from happening. One is additional treatment such as the UV system.
The other is to “reduce opportunities” for infection by implementing a “robust” watershed management plan “in light of (the) outbreak,” he said.
Specifically, the city must be diligent about monitoring the watershed so cattle are kept out at crucial times -- especially when the city is diverting water from Elk Creek.
Baker City is one of four Oregon cities that is exempt from a federal rule that requires drinking water from surface sources, such as streams, to be filtered. The others are Bend, Portland and Reedsport.
Leland told the councilors that Baker City is different from those other cities, though, because there’s an active grazing allotment bordering Baker City’s watershed.
City and state officials are focusing on Elk Creek for a couple of reasons.
First, a water sample taken from Elk Creek on Aug. 4 contained 913 crypto oocysts. No other sample taken from any source has contained more than three oocysts.
(A person can become ill after ingesting as few as 10 oocysts, although the infectious dose depends on a variety of individual factors; also, some people who are infected never have any symptoms.)
Second, officials have found evidence that cattle have entered the watershed during the past two weeks.
Officials collected samples of feces from cattle, deer and elk in the Elk Creek area; tests are pending.
Any of those animals, or a different species, could have been a source of crypto.
“We may not be able to get to the bottom of this,” Leland said. “But that doesn’t mean we shouldn’t keep looking.”
Councilor Dennis Dorrah said that it’s the city’s responsibility alone to keep cattle out of the watershed.
Mayor Richard Langrell agreed.
Councilor Clair Button suggested that the councilors could talk to the Forest Service about helping to keep the cattle at bay.
The Foster Ranch has the permit to graze cattle on Forest Service land adjacent to the watershed.
Michelle Owen, the city’s public works director, emphasized after the meeting that the watershed fence is only one part of the watershed protection strategy.
A perimeter fence that the city plans to install, but has not yet done so, would only keep cows from getting close to Elk Creek itself. The fence wouldn’t stop rain or snowmelt runoff, which could contain crypto, from flowing into the creek.
Crypto can survive for several months in feces or soil.
This is why all parties that own or use the land surrounding the watershed need to be involved in keeping cattle away from the watershed, Owen said.
City Manager Mike Kee said there is also a need to keep human trespassers out of the watershed. He said he has seen photos of people smoking cigarettes in the watershed.
The 10,000-acre watershed is closed to people, although the city normally allows deer and elk hunters to hunt in the area if they ask for a permit first.
The city doesn’t plan to allow hunting this year, however, due to the extreme fire danger.
Owen pointed out that hungry cattle during their normal grazing season help reduce the amount of vegetation that could fuel wildfires.
Langrell and Dorrah said they are in favor of treating the city’s water with UV lights.
Cost is a large factor, both have said, because a UV system would cost about $3 million, and filtration would likely cost at least six times more.
A UV system also would cost much less than a filtration plant to operate once it’s built, Dorrah pointed out.
A 2009 engineering study for the city estimated the construction cost of a UV system at $2.3 million, with an annual operating expense of $13,000.
A filtration plant was estimated at $17.7 million, with an annual operating expense of $332,000.
Councilors Roger Coles and Mike Downing said they are wary of UV and would prefer filtration.
Both are concerned about the potential for wildfire-related runoff entering the water supply. Filtration can remove ash and dirt from the water while UV cannot.
But Councilor Clair Button contends that UV still would be viable even after a catastrophic fire in the watershed because the turbid water from the affected area in the water system could be turned out and another source tapped.
Councilors Kim Mosier and Barbara Johnson said they need more information before agreeing that UV treatment is the city’s best option.
Mosier wanted more time to think about the concept, while Johnson said she would like assurance that a UV system wouldn’t be rejected by state and federal water officials.
The concern, which Coles and Dorrah have cited in the past, is that the city would build a UV plant and then be required to supersede that plant with filtration anyway.
The deadline for Baker City to have a treatment facility operating is October 2016. In 2011 state officials extended the deadline from October 2013.
City officials also want to expand available groundwater resources to supplement the aquifer storage and recovery project (ASR). This would include improving the well at the Quail Ridge Golf Course, which is not being used now.
The city is considering trying to tap two other wells.
The sites weren’t directly identified but one is just outside the city limits. The other is privately owned at a location where the city once had rights for use, Kee said.
Langrell and Dorrah said they want to see this happen. Dorrah asked for various usage totals to help determine needs.
Coles asked if it were possible to tap into water below municipal airport property as another source.
Kee said that’s a viable option.
He also intends to present financial options to the councilors during their next meeting, which would be on Sept. 10, to speed up the planning process for construction of the UV system.
No action on firearms
The councilors postponed updating city code about possession of concealed handguns in city parks.
They asked to speak with Police Chief Wyn Lohner before deciding how to modify the current city code so it conforms with state possession rules.
The councilors were asked to either:
• Amend current rules to prohibit loaded firearms in all parks except those authorized by law to carry loaded firearms in public places.
• Or, remove references to regulating firearms in city parks in the current rules.
Kee said Lohner was “neutral” about the matter.
Langrell pointed out that it would be “a nightmare” to figure out whether someone is actually carrying a loaded firearm.
Brent Smith, the city’s attorney, brought up the inconsistency between the city’s ordinance and the state law.
Engineers urged UV in 2009 memo
By Jayson Jacoby
The Baker City Council’s decision Tuesday to continue planning for installing an ultraviolet light system to protect drinking water from cryptosporidium follows the recommendation an engineering firm made almost four years ago.
In a Nov. 22, 2009, 18-page memo to Michelle Owen, the city’s public works director, three officials from HDR Engineering Inc. recommended a UV system over three other treatment options: ozone, chlorine dioxide and membrane filtration.
The engineers ranked the four treatment methods based on several criteria, including construction cost and annual operating expense, reliability, complexity and ability to protect water from a variety of threats other than crypto.
UV ranked first with a total score of 708 points, followed by membrane filtration (539), ozone (532) and chlorine dioxide (381).
“UV is the least expensive option, simple to operate, reliable, and fits well into the gravity flow hydraulics of the existing water system,” the engineers wrote in the memo.
They noted, however, that the advantages of UV treatment depend on the city continuing to convince state and federal officials that the city does not need to filter its drinking water to ensure it’s safe.
Most cities that use surface water, as Baker City does, have to filter the water to meet federal standards.
Baker City is one of just four Oregon cities that use surface water but have an exemption from the filtration requirement. Bend, Portland and Reedsport are the others.
“For UV disinfection to be sufficient treatment into the future, the City must maintain its exemption from filtration,” the engineers wrote.
They also pointed out that a UV system would not protect the city’s water from the possible effects of a fire in the city’s forested, 10,000-acre watershed.
“Protection against forest fires and maximum reduction in regulatory risk could be achieved by membrane filtration, but at significant additional expense,” the engineers wrote.
They estimated the construction cost of a filtration plant at $17.7 million, with an annual operating cost of $332,000. The UV plant construction cost estimate was $2.3 million, with an annual operating cost of $13,000.
Filtration had the highest rank in two criteria: water quality and reliability in meeting future regulatory requirements.