The Broadway Improvement project in Tucson, AZ, extends from Camino Seco to Houghton Road and is part of the voter-approved Regional Transportation Authority (RTA) plan. The project will widen the roadway to a four-lane divided cross section with multi-modal improvements, significant drainage crossings, and water harvesting and streetscape improvements on this two-mile segment of Broadway Boulevard. A customized HAWK crossing would need to be incorporated into the project to accommodate a future bike boulevard crossing the corridor. The budget for the improvements is very limited. The improvements need to connect to the previously constructed improvements at Camino Seco, Harrison Road and Houghton Road intersections, and minimize impacts to surrounding properties.
Using performance-based design and AutoCAD Civil3D design modeling, Kittelson applied an innovative integrated design process in order to complete the preliminary and final design efficiently.
• Laser scanning was used for data collection to ensure that all existing infrastructure data were collected.
• The 3D model visually presented the impacts of the improvement in the design process, resulting in an optimized design that minimized impacts; the model was also used to identify and modify multiple utility impacts along the corridor.
• The integrated design approach enhanced collaboration between stakeholders and design team, allowing for custom solutions to the sidewalk, water harvesting, and drainage design solutions, as well as integration of new public art features along the corridor.
Spreading the Word in 3D
Kittelson completed the preliminary design and conducted an open house, using the 3D model to explain the improvements to the public. 3D renderings and fly over movies were generated at a 60% completion stage in order to provide an enhanced understanding of the final product for the public and the stakeholders. Through the use of software tools, automated plan production increased the design efficiency. The contractor will have access to the electronic model files, which will assist in creating accurate bids and pricing. The 3D data will be available to the contractor to incorporate into their construction models including automated equipment without needing to recreate the data from paper.