Dieppe Manor - Seniors Living Grande Prairie, Alberta. Dieppe Manor is a self-contained seniors apartment that consists of 71 units. Located in the northern part of the city. 9428-121 Avenue, Grande Prairie. (780) 539-1451. Rent for apartments is based on 30% of income. Heat, water & sewer is included, and laundry is free. Meal services are available. Access to nursing and personal care. There are regular activities and events.