Our Water team in Sitka, Alaska, is contributing to the largest public works project in Sitka’s history. Sitka, located on the west side of Baranof Island in the southeast panhandle Alaska, receives nearly three times more rain that Seattle – supplying enough water to operate two hydroelectric power plants. The power plants provide 100 percent of the city’s required electricity; however, with rising oil prices and significant growth over the past several years, Sitka has been relying more heavily on electric heat.
Rebecca Venot/ANC was featured in an article in the Daily Sitka Sentinel
In an effort to maintain energy independence, Sitka initiated the Blue Lake Expansion Project. This includes increasing the height of the Blue Lake Dam by 83 feet, which impounds Sitka’s pristine and unfiltered drinking water; and building a new intake, surge shaft, and powerhouse. When completed, the expansion will provide approximately 27 percent more electricity for Sitka.
Rebecca Venot/ANC said, “While the dam powerhouse work is being conducted, the city’s water supply will be offline for approximately 2 months. Our Seattle- and Anchorage-based design team, including Bill Badgeley/SEA, Steve Bakken/SEA, Matt Haapala/ANC, Ginger Knox/SEA, and Zheng Jie/SEE, managed by Kim Ervin/SEA, designed a temporary filtration plant to be installed at a different water source on the island to ensure the community has a safe and reliable drinking water supply during the outage.”
The temporary filtration system will employ four mobile microfiltration membrane trailers that provide water to six 19,000-gallon chlorine contact tanks. The system is designed to treat a lower quality source than the typical supply while minimizing impacts to Sitka’s residents and meeting all required drinking water regulations.