Hours Of Operations Otter Tail Power Company Minnesota Mahnomen 56557 Otter Tail Power Company Hours of Operation and Location in Mahnomen, MN 56557 4.4 - 81 votes (218) 935-5660 Get Directions Otter Tail Power Company Hours Category: Home & Garden Hours Hours may vary due to season or holiday reasons. For specific hours, please contact store directly. Map Explore MahnomenView More Apparel DebExpress Recommend For You Peoples Gas Pepco Runnings Farm & Fleet United Power Duke Energy Entergy Ferrellgas Toys R Us A Finishing Touch A Healing Touch