Daily Sitka Sentinel

All Systems In Place For Alternate City Water

By SHANNON HAUGLAND
Sentinel Staff Writer
    The new water filtration system at Indian River will be intermittently tested starting Tuesday, with treated water flowing into the city’s water distribution system, the city water division has announced.
    Indian River will supply drinking water for the city while the regular water source, Blue Lake, is off line for about two months while a new intake is installed at the lake as part of a dam expansion project, said City Environmental Superintendent Mark Buggins.
    Indian River was the main drinking water source for Sitka through 1984. To meet current state and federal drinking water standards, the city has installed extra treatment facilities at the Indian River water treatment plant. The equipment is housed in four container vans that are parked outside the treatment plant.
     Buggins said when Indian River water goes online people may note a stronger chlorine taste than they are accustomed to in their Blue Lake water.
    The portable filtration system was designed by CH2M Hill and installed by Barnard Construction at a cost of $4 million. The expense was included in the Blue Lake dam construction costs.
    The city will operate the leased system using municipal water division employees.
    Buggins said that after the phased-in trial starting Tuesday, he estimates that the system will be switched over to Indian River water full time sometime in August.
    “For the first few days we’ll be mixing Indian River water with Blue Lake water, and run the Indian River source at a lower production rate, and get them all tuned up together,” Buggins said Friday. “We’ve been testing the parts individually last week, getting all the tanks disinfected, testing each pump and setting up the automated system.”
    Blue Lake is expected to be offline from the end of August through the end of October, when work on the tunnels at Blue Lake is taking place, Buggins said.
    The temporary water system will employ six 19,000-gallon tanks that will be filled with treated water from Indian River, Buggins said. Holding the water in the tanks for a certain period provides the “contact time” for the chlorine to take effect before the water is piped throughout the town.
    The temporary filtration plant puts the river water through filters that are one-tenth of a micron, Buggins said. As a unit of measure, a micron is 1/25,000 of an inch, so the filters will trap particles as small as 1/250,000 of an inch in size.
    The city has received calls from some citizens about the water from Indian River, particularly those with compromised immune systems, and the city has assured them the water is safe.
    The supply of fresh water will be adequate for all present needs, including the fish plants during their busy summer season, Buggins said. In the summer the city uses about four million gallons a day, he said.
    “This plant is sized for that,” he said.
    Nevertheless, Buggins encourages conservation. “Any wasting of water ... chlorine: it’s expensive,” he said.
    He said he feels the changeover process is going well, but there is some stress involved.
    “Any time you’re messing around with water, it’s a high stakes thing,” he said. “I’m not overly nervous, but I’ll feel better after we’ve run the system four or five days consistently.”
     He noted that the quality of water in Indian River is very good, although not as good as Blue Lake.
    “It’s better than most rivers – high quality,” he said. “But Indian River has a higher chlorine demand than Blue Lake and we’ll use up more chlorine. Blue Lake is so clean and the demand for chlorine is so low.” He noted that Indian River will have a chlorine residual of 1.6 and Blue Lake, by comparison, has .65.
    Additional information is available at 907-747-1806 or chaix@cityofsitka.com.