Investigating factors affecting energy consumption in rural Alaskan water treatment and distribution systems, and exploring energy-saving strategies for wastewater treatment in cold climates

• Main Author: Rashedin, Muradur
• Other Authors: Aggarwal, Srijan, Dev, Subhabrata, Schiewer, Silke, Huang, Daisy
• Format: Thesis
• Language: English
• Published: 2023
• Subjects: Rural sanitation; Sanitation; Energy conservation; Water treatment plants; Cold weather conditions; Sewage; Purification; Rural water-supply; Water-supply; Master of Science in Civil Engineering; Fairbanks; permafrost; Alaska
• Online Access: http://hdl.handle.net/11122/13247

Thesis (M.S.) University of Alaska Fairbanks, 2023 Underlying permafrost in rural and remote Alaskan communities creates difficulties in connecting these communities to the electrical grid, resulting in the import of fuel from nearby cities by air or barge for electricity generation. During the winter months, a large amount of fuel and electricity is required for water treatment and distribution in these communities to keep the water temperature above freezing. Furthermore, domestic wastewater in rural Alaska is treated within wastewater lagoons, which lose their treatment efficiency during the freezing winter months. In contrast, the biological aerated filter (BAF), which has become an efficient alternative for domestic wastewater treatment in off-grid houses, consumes higher energy in the form of continuous aeration. As a result, residents living in rural Alaska pay significantly higher utility costs compared to the national average. This study is designed with two goals, to determine the factors contributing to higher energy consumption for water treatment and distribution and to evaluate energy consumption and BAF performance for wastewater treatment at different aeration regimes. The overall study is based on the following two hypotheses: (i) factors including seasonal changes, geographical regions, population size, and water distribution system (WDS) types influence energy consumption for water treatment and distribution, and (ii) intermittent aeration saves energy without impacting BAF performance for wastewater treatment. After analyzing energy audit data from the Alaska Native Tribal Health Consortium (ANTHC) for 78 rural Alaskan communities, we found that average per capita energy consumption was highest in interior Alaska (1826 kWh), followed by Northern (917 kWh), Southwestern (660 kWh), Gulf Coast (492 kWh), and Southeastern (136 kWh) regions. Among the water distribution system (WDS) types, piped circulating systems showed the highest energy consumption (1100 kWh), followed by washeteria (1000 ...