NorthRim Engineering

At over a thousand square miles, Kenai Fjords National Park features numerous glaciers. Wildlife thrives in icy waters and lush forests around this vast expanse of ice. One of the top tourist destinations is Fox Island, centrally located in Resurrection Bay.

In early 2016 Cook Inlet Region Inc. (CIRI) Alaska Tourism Corporation requested NorthRim Engineering lead a fast-track design-build for a new advanced wastewater system for Kenai Fjords Tours Fox Island. The goal was to design, construct, and obtain Alaska Department of Environmental Conservation (DEC) discharge permits for an advanced wastewater system prior to the influx of summer tourists.

To propel this accelerated design-build project would require close coordination with DEC, CIRI, Kenai Fjords Tours, Orenco Systems Inc., Anchorage Tank, Harmon Construction and associated contractors. As a former DEC District Engineer, I was keenly aware that DEC could make or break this timetable.

Fox Island attracts both day-trippers and overnight visitors. Kayakers can land at the long gravel shoreline. Large tourist boats disembark at the extended dock. A day lodge, kitchen, employee housing, and public restrooms are located at the north end near the dock. Heading south 1500 feet down the strand are 3 cabins, 4-plex cabin, and wilderness lodge. These facilities all require wastewater collection, treatment and disposal.

The previous system consisted of primary treatment with ocean outfall lines. The new advanced wastewater system could utilize the outfall lines if they were intact and of sufficient size. Storm Chasers Marine Services, Inc. assembled a dive team to investigate the outfalls. Underwater videos were taken showing the HDPE lines to be in good shape. Engineering calculations demonstrated the outfall lines could be used for the new advanced wastewater system.

 

At the heart of the design was the Orenco Advantex Treatment System. This premier wastewater treatment technology is used worldwide; I had recently inspected systems in remote New Zealand. Anchorage Tank is the local distributor for this system. I have designed many systems throughout Alaska using this proven technology. Orenco engineers and Anchorage Tank reviewed the NorthRim Engineering design and selected the Advantex AX-Max units. The new design utilized the north outfall (North System) and the south outfall (South System). Mobilization was via Seward.

The North System treats waste from the kitchen @ 375 meals/day, public restrooms, and 22 employees housing totaling 1,631 gallons per day (GPD). Wastewater effluent will continue through the existing septic tanks, followed by a new 1500 gallon S.T.E.P. tank (lift station). The S.T.E.P. tank will provide additional primary treatment and pump the effluent to the AX-MAX125-35 unit, with treatment capacity of  3,000 GPD peak load. The AX-Max unit will treat the effluent, disinfect by UV, and discharge via gravity flow to the existing north outfall line.

The South System treats waste from the 3 cabins center area, 4-plex cabin and wilderness lodge. The 3 cabins in the center area are connected to a new 1500 gallon S.T.E.P. tank, and the effluent is directed to the South System AX-Max unit via force main. The 4-plex cabin and wilderness lodge will likewise have effluent pumped from a new 1500 gallon S.T.E.P. tank to the AX-MAX075-14 unit. This 14′-long unit is also capable of treating a 3,000 GPD peak load. This will easily treat the 1903 GPD design flow.

DEC issued design approval in early May. Construction crews immediately began work. Harmon Construction was the general contractor based in Seward. Construction was completed by mid-May. Final inspections took place immediately after construction was complete.

DEC issued a wastewater discharge permit effective May19, 2016. DEC issued the approved DMR form for General Permit Authorization, AKG572103, for the Fox Island Wastewater Treatment Facility. The Discharge Monitoring Report requires regular sampling for dissolved oxygen, biochemical oxygen demand, pH, total suspended solids, and bacteria. The superior treatment level of the AX-Max units does not require a mixing zone.

NorthRim Engineering completed Record Drawings and DEC issued final operational approval in April 2017. The project successfully operated for the 2016 and 2017 seasons. The final inspection was made by kayak, this allowed close shoreline inspection and wildlife viewing.