Wrangell continues to brace itself for summertime demand on its treated water, after bottlenecks in production last year led to a critical shortage.
Public Works director Amber Al-Haddad has been keeping the Borough Assembly up to date on conditions at the treatment plant and its reservoirs, and so far reports have been on the positive side. Water in the two reservoirs is close to full, with the upper reservoir down by about two feet.
The biggest worry is that the plant’s primary filtration system – consisting of four large bays of special sand that water passes through – will clog in quick succession as water demand increases with the seafood processing season. Usage is generally greatest from the end of June through the middle of August, when Wrangell’s two processor plants are contending with the salmon harvest.
When water passes from the lower reservoir to the plant, it first goes through an initial roughing filter that removes some organics. It then is diverted into one of four slow sand filtration bays for treatment, with water seeping through the material and leaving particulate behind. From there, treated water goes to one of two storage tanks before being fed into the wider utility system.
Several circumstances with the operation of Wrangell’s plant have made this process problematic. For starters, the type of plant is itself not
well suited to the available water supply, with higher amounts of sediment and
organics coming from the town’s reservoirs than was first anticipated. The roughing filter was supposed to help limit this, but due to a designed inability to flush itself has a tendency to clog and is of limited effect. Clearing the filters has proven to be a time- and water-intensive process.
Also, while the sand is supposed to be skimmed, disposed of and periodically replaced, over its 17 years of operation the material at Wrangell’s plant has never been changed out. The main reason for this has been a matter of cost, with material costing close to $500,000 to replace shortly after its construction and double that presently.
Assembly members had considered replacing sections of the material on a filter-by-filter basis, approving such a move in April but reversing course soon afterward. It was recommended by engineers that the material be replaced all at once for best efficiency. Assembly members instead have opted to focus on an application for federal grant or loan funding that would enable construction of a new plant better suited to the local water supply.
In the meantime, money has been approved to upgrade the roughing filters in order to allow it to automatically flush and regulate itself. The Department of Environmental Conservation is currently reviewing plans for the redesign, and Al-Haddad reported her department is still awaiting a decision.
“We’ll have to wait until they give their approval,” she said. However, work on materials procurement can get started preemptively, so that the project can be undertaken shortly after receiving approval.
For the sand filter units, a new method of plunging sediment from the bays has proven successful, extending turnaround time between cleanings from four or five days to about three weeks. Four temporary staff hired on for the summer have supported the three employees assigned to water and sewage treatment in this effort.
“That’s been a huge benefit to our cause,” Al-Haddad said.
Staff will give the filters another aggressive cleaning by the start of next week, ahead of the expected climb in demand. The pace of their work keeping the filters clear will depend on a combination of factors, from actual usage to the turbidity of the water coming from the reservoirs, which varies depending on the amount of rain received.
An emergency response plan is being drafted that would direct city staff in the event of a water shortage. A campaign to reach out to community members encouraging them to be more mindful of water waste and usage habits this summer will also be underway this month.
At its last regular meeting on May 29, the Assembly revisited progress being made on the water treatment plant, as well as approving a first-reading draft ordinance that would eventually allow for metering of residential and smaller use commercial connections. The Assembly is also considering an adjustment to water rates that better reflect cost of production.
If adopted next week, the ordinance would be part of a wider effort on the part of the city to tighten up use of treated water. An alleviation of the city’s production problem appears a long way off. Even if funding and plans for a new treatment plant could be obtained, the process of building one could take between three and five years, according to Carol Rushmore, acting city manager.
Beyond readjusted rates and metered water, a new area of consideration Assembly
members addressed at last week’s meeting was free ridership in the use of treated water. Member Stephen Prysunka noted that public faucets such as the one at the Shoemaker Bay Harbor parking lot have been used by residents further uproad to replenish their water supply, though to what extent is immeasurable.
Finance director Lee Burgess explained that some sort of payment unit regulating such taps could be installed, but the savings may be outweighed by the costs.
“Relative to the amount of water that goes through there it’s not definitive it would be worth it,” he told the Assembly.
Noting there are other sources of water available, Mayor David Jack had a simpler suggestion: “It wouldn’t cost much to put a lock on there.”
Their next meeting has been scheduled for June 13 at 7 p.m., inside City Hall. It will be preceded by a public hearing on the water ordinances at 6:30 p.m.
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