4th Avenue Streetscape Improvements

4th Avenue in Downtown Anchorage is a popular destination for both visitors and locals. While the project began as a lighting and traffic signal replacement effort, it expanded to include the streetscape when the extent of disturbance needed to make electrical upgrades were recognized. An assessment of the streetscape was completed, with a white paper developed that provided recommendations to guide its design. A critical discussion was the inclusion of street trees, but ONLY if they were treated as valuable green infrastructure and provided with the resources, they needed to survive. Beyond the design of a streetscape that prioritized pedestrian movement and visual simplicity, twenty-one street trees were included in the design. The three challenges for street trees in Anchorage are physical damage from snow-clearing activities, chemical damage from snow-melt products, and lack of access to adequate quantities of quality planting soil. The typical tree was designed to include approximately 700 cubic feet of soil below the sidewalk within structural soil cells. It was planted within a raised planter bed to eliminate physical and chemical damage. Four tree locations were also provided with monitoring systems that will provide data on soil temperature and moisture. This will allow the development of appropriate maintenance regimes. The project process included detailed visual simulations to communicate with stakeholders and refine the placement of planters and light poles to minimize impacts on adjacent businesses.