Water seems to be fine at start of summer

The glass appears to be on the half-full side for Wrangell's water situation, as the season for peak usage of the resource starts up.

"Our outlook is very good right now," reported Amber Al-Haddad, director for Public Works.

While reservoir levels have dropped slightly since the spring due to drier than usual weather conditions, raw water reserves are still looking healthy. The city's treated water supply comes from a pair of open reservoirs, with the treatment plant drawing from the lower of them. Together, their maximum capacity has been estimated at 56,700,000 gallons, though sediment build-up in the lower reservoir has gradually diminished its available volume.

Despite being in a temperate rainforest, keeping the reservoirs full and flowing has at times proven difficult. Most recently, diminished reserves in late February led to several weeks of emergency restrictions on water usage. In winter, a combination of residents running their taps to prevent freezing and breaks in the distribution system led to high demand, comparable to the peak needs Wrangell sees in the summertime.

Most of the additional summer demand comes from Wrangell's two seafood processors, Trident and Sea Level. The former just began its operations on Tuesday, while the latter had its crew ready to go when the commercial crab fishery began on June 15. Peak for both usually lasts from late July into August before drawing down to a close.

Al-Haddad said Public Works will be coordinating with the two on water availability through the upcoming season, and also with the Harbor Department, another source of increased demand during the summer.

Besides the reservoirs, the other potential kink in the town's water supply chain is the treatment plant itself. For most of its almost two decades in service, the plant sand-based filtration system has proven prone to clogging from the moderately sedimented water it draws upon. The four primary filter bays have to be taken offline in turn for periodic cleaning as a result, the frequency ranging from weeks to sometimes mere days apart depending on the demand. When one bay is taken offline for maintenance, overall output is cut down, making it harder for the plant to keep its treated reserves full during high demand.

These operational shortcomings led to a serious production shortage in the summer of 2016, causing disruptions to the processor plants and leading to a declaration of emergency by the mayor. In the years since, the City and Borough Assembly and municipal staff have worked out an emergency response plan and have beefed up the water plant's staff with temporary workers ahead of the summer rush.

One additional staffer was called upon this spring, adding to the plant's three regular workers, who also work the sewage treatment plant.

"They did some aggressive sand cleaning," said Al-Haddad. "We've been keeping up with the sand filter and roughing filter maintenance."

Since 2015 the city has been looking at alternative models better suited to its water supply and demand. A plant using dissolved air flotation (DAF) was recommended by consultants, a method which removes unwanted sediment and impurities from the water using bubbles and skimming. A miniature test plant was given a successful trial run in 2016, a contrast to the main plant's production shortcomings that summer.

Costs for the DAF plant would run at around $9.1 million, including $860,000 needed to improve the plant's filters and water recapturing. Though pricey, estimates were brought down from an initial $13 million price tag by making use of existing plant infrastructure.

To pay for this, the city has approached the Department of Agriculture for $3.82 million in loans and $3.16 million in grant monies, with another roughly $3 million grant to be applied for through the Alaska Economic Development Administration. Remaining funds would come through the borough's reserves and other, smaller grant sources.

"We're in a bit of a holding pattern," said Lisa Von Bargen, Wrangell's city manager, in an update on the project's progress.

The city is still awaiting a decision on the AEDA loan. The agency's head visited Wrangell earlier this spring to review the project and help with the application. Von Bargen expected to know more toward the end of August.

 

Reader Comments(0)

 
 
Rendered 11/11/2024 17:09