Celebrating the 7th National Roundabout Week!

This week at Siegfried, we celebrated the 7th National Roundabout Week! Created by the DOT Federal Highway Administration in 2018, every third week of September promotes the numerous benefits of roundabouts.

The Benefits of Roundabouts

Over 10,000 roundabouts have been installed in the United States and can reduce fatal and serious injuries. This is mainly due to the channelized, curved approach that forces drivers to slow down and yield to oncoming traffic. But aside from its unique design, roundabouts offer numerous benefits to both drivers and communities.

They Enforce Safety

Roundabouts can significantly enhance safety at intersections, reducing fatal and serious injuries by up to 82%. Conflict points, the places where vehicles cross paths, are minimized due to the circular design. By lowering vehicle speeds to between 15 and 25 mph, roundabouts create a safer environment for all road users, particularly benefiting pedestrians and cyclists.

They are Cost-Effective

Because roundabouts don’t require signal equipment installation, power, and maintenance, they don’t cost as much to implement. More money is saved over time because they don’t require equipment maintenance or repair as opposed to their traffic signal counterparts.

They Improve the Flow of Traffic

Roundabouts help improve the flow of traffic. They reduce the need for traffic signals, allowing vehicles to move continuously and reducing traffic delays and stops by up to 74%. Roundabouts are also instrumental in handling higher volumes of traffic more efficiently than a traditional intersection, decreasing congestion. They promote safer merging and diverging, preventing accidents and allowing for smooth traffic.

They Are Environmentally Friendly

Roundabouts cause less vehicular pollution than traffic signals due to less idling and stop-and-go patterns. This helps to lower fuel consumption and greenhouse gas emissions. Lower speed requirements also contribute greatly to lower noise pollution. The creative designs could also incorporate green spaces and landscaping, which improves air quality and could even provide habitats for wildlife. At Siegfried, our Swain Road and Montauban Avenue Roundabout design incorporated landscaping architecture to include a green space in order to help keep our city of Stockton environmentally healthy.

Our Approach

To create an efficient design, roundabouts undergo a process that works to balance safety and capacity. Achieving that balanced design where capacity, safety, and minimal cost are optimized is what makes roundabout plans unique. Modern roundabout blueprints require a heuristic principle-based approach that emphasizes the goal of making roundabouts safe and efficient. Understanding the trade-offs between cost, safety, and capacity is key to achieving an optimal and balanced design.

Through our innovative design process, we aim to reduce vehicle delays, increase capacity, promote traffic ergonomics and safety, and reduce speeds. Our process will enhance road safety and improve the quality of life for pedestrians and cyclists. Take a look at some of our roundabout projects below.

Siegfried Roundabout Projects

City of Stockton, Miner Avenue Complete Streets

Completed in 2022, Siegfried provided civil engineering, landscape architecture, planning, and surveying services for the ASCE Award winning, Miner Avenue Complete Streets project. This project was a 10-block rehabilitation of Miner Avenue that spanned from Center Street to the UPRR underpass. ATP grant-funded, Phase I consisted of the first four blocks of bike and walkway improvements, plus the GMAQ-funded roundabout at the San Joaquin intersection. Improvements included: lane reduction from four to two lanes and Class II bicycle lanes; the addition of median islands and the roundabout; traffic signal modifications at the signalized intersections; streetlights; as well as wider sidewalks with pedestrian and bicycle amenities.

City of Stockton, Swain Road and Montauban Avenue Roundabout

Swain Road and Montauban Avenue in Stockton serve as important east-west and north-south corridors. The City of Stockton recognized the need to increase safety and efficiency while at the same time reducing congestion by converting a four-way stop-controlled intersection with a roundabout at the intersection of these two roads.

UC Davis, Geidt Pathway and Bioletti Turning Circle

In anticipation of approximately 1,500 new bicycle riders originating from the adjacent Tercero Hall, UC Davis enhanced pedestrian and bicycle connections throughout the campus with the Geidt Pathway and Bioletti Turning Circle. Overall circulation was improved by incorporating a new roundabout, realigning the bicycle pathway, and providing connections to other adjacent destinations. Relocating on-pathway bicycle parking both minimized conflict and reduced pedestrian and bicycle conflicts. High-value trees that are unique on campus were preserved throughout the corridor.

Statistics provided by Department of Transportation, Federal Highway Association.