Sitka environmental superintendent Mark Buggins looks over the temporary filtration  plant at the Indian River. Buggins says August is "not the best time" to drink from the Indian River, but "it is what it is." (KCAW photo/Robert Woolsey)

Sitka environmental superintendent Mark Buggins looks over the temporary filtration plant at the Indian River. Buggins says August is “not the best time” to drink from the Indian River, but “it is what it is.” (KCAW photo/Robert Woolsey)

Sometime in August crews working on the Blue Lake hydro project in Sitka will shut off the old penstock from the dam and connect a new one — work that will leave the town without its drinking water supply for up to four months. In the meantime, the city is returning to its former water plant on the Indian River, but it’s not a matter of turning a few valves.

Because of higher drinking water standards, Sitka has rented a temporary filtration plant — at a cost of about $1-million per month.

 

Note: The general contractor for the Indian River filtration plant is Barnard, the same contractor overseeing the Blue Lake Hydro expansion. The Anchorage-based engineering firm CH2M HILL designed the system. The $4-million  cost is part of the overall $157-million Blue Lake project.

Walking with Mark Buggins along the Sawmill Creek pond…

Buggins: This is my first official tour. Let’s follow the flow of water.

When I moved first moved to Sitka years ago, I often brought my golden retriever to this man made pond by the Indian River. I’ve thrown a slobbery tennis ball in here probably a thousand times. Now we’re drinking from it.

Buggins: In the days since Blue Lake came on, this was our main source of water in town. The couple times in the last 20 years that we’ve turned Blue Lake off to do penstock inspections, or maintenance in the penstock, we’ve supplied water completely by Indian River.

The last time Sitka used  the Indian River exclusively for water was in 1984, a few years before my dog played in it. But a lot has changed since this plant was decommissioned. Mark Buggins, Sitka’s environmental superintendent, says sand filtration and chlorine no longer meets the standards of the state Department of Environmental Conservation. The few times Sitka has relied on the Indian River over the last thirty years we’ve had to boil the water — even after it’s been treated.

Buggins:  So a boil water notice pretty much paralyzes businesses. Restaurants can’t wash dishes with the water, they can’t serve people without treating it somehow — boiling it or treating it themselves. Doctor’s offices, dentists — it’s really not an option.

So that’s why the Indian River water plant now looks like a truck stop. There are four huge truck trailers parked here containing the actual water filters, another trailer with a standby emergency generator, six trailers that serve as holding tanks, and enough pumps, piping, and control valves to supply a … well, a small town.

Paula Stapf, with Pall Corporation, has taken her filter trucks all over the world. (KCAW photo/Robert Woolsey)

Paula Stapf, with Pall Corporation, has taken her filter trucks all over the world. (KCAW photo/Robert Woolsey)

Buggins takes me into one of the trailers with filters and introduces me to Paula Stapf, an engineer with Pall Corporation, which is supplying the filters.

She’s seated at a laptop computer, monitoring the Pall Mobile Membrane Filtration system.

Stapf:  So what we’re doing is mechanically filtering the water, and the material that we’re removing is not only causing turbidity in the water, we’re filtering down to the microbe. So we’re able to remove Giardia and Cryptosporidium — these are the organisms that would make the public sick. And it’s a purely mechanical operation. Each of these mobile trailers can do a max flow rate of 840 gallons a minute.

Buggins looks over the PLC display (Programmable Logic Controller). It's a computer, and Sitka has purchased it, along with several of the pumps and valves in the temporary system. (KCAW photo/Robert Woolsey)

Buggins looks over the PLC display (Programmable Logic Controller). It’s a computer, and Sitka has purchased it, along with several of the pumps and valves in the temporary system. (KCAW photo/Robert Woolsey)

A programmable logic controller — or PLC — is running the whole show. There’s a touch screen in the old Indian River pump house. Stapf is going to train Sitka’s water department to control the system’s automation , but it’s her job to keep it running — doing maintenance from plumbing to wiring.

Water is a pretty important business, globally. Stapf gets around.

Stapf: I’ve been to all of the states in the US except Hawaii. And I’ve been in most of Canada. We’ve taken these systems to Africa, over in Asia, Australia — so some international (work) as well.

Each trailer has two banks of filters — 40 per bank. Each filter is a six-inch plastic pipe, about 10 feet high, containing 6,000 individual fibers the size of hollow spaghetti noodles. They last about 10 years.

Not everyone in Sitka is comfortable with going back to Indian River water — especially with the salmon just starting to run — but as we head into the old water plant building, Mark Buggins says Sitkans haven’t complained.

Buggins: So yesterday, we ran Indian River into the system from 8:30 AM to about 3:30. And we plan to do something similar to that today. We started around 8:30 — turned Blue Lake off, turned Indian River on.

The main issue for taste is not fish — but chlorine. Although there are six huge tank trucks holding the Indian River water while it’s chlorinated, there’s not as much so-called “contact time” as there is when the water travels all the way from Blue Lake. So the dose of chlorine is somewhat higher.

Still, all those salmon. The timing of this project is controlled by the levels in Blue Lake — the new penstock tunnel can only be hooked up when the lake is at it’s lowest natural level, which happens every August. Buggins agrees its not an ideal time to be drinking from the Indian River. But he’s not guessing that it will taste okay. He’s tried it out on the folks paying the tab.

Buggins:  We did taste tests last year, with the assembly and the general public just stopping by before an assembly meeting. And we also did a second round of taste tests, kind of near the end of the fish run, and there was mostly dead fish in the river, and hadn’t had a storm to wash them out yet. Most people seemed to like the water better that had been chlorinated before going through the microfilters. We did the taste testing — but it is what it is. Right now there are now fish in the river, but I  personally couldn’t tell the difference between the Indian River water yesterday and the normal Blue Lake water.

Buggins says he’s coordinating with the Sitka Sound Science Center — which also draws water from the Indian River for its hatchery — to make sure that there is adequate flow of water for fish. But he’s not too worried. The Indian River has supplied Sitka for decades in the past and, with a little help from technology, should see the town through the next 120 days.