In early November, the Ada County Highway District installed Traffic Logix rubber speed cushions to slow traffic on Bison street. The cushions were installed in response to resident complaints of speeding vehicles. While the first request for traffic calming was denied, the residents appealed the decision and the district’s commissioners unanimously approved the appeal.

When a new development was built on the ridge above Bison, the formerly quiet neighborhood street became a through street for the new residents. At least one incident was formally reported of a driver unable to make a turn due to excessive speed, who instead drove over the sidewalk and onto someone’s property. Several similar episodes were also reported anecdotally.

Traffic Logix rubber speed cushions were selected for this project. Since Bison is used by emergency vehicles headed to the above development, it was imperative that the devices not slow response time. While speed humps cause all vehicles to slow down, speed cushions are constructed as several small humps with spaces between them. The devices force cars to slow down while riding over them while the wider axle on EMT vehicles can straddle the middle cushion without slowing down.

The Boise Fire Department approved the Traffic Logix rubber speed cushions for use due to their compatibility with emergency vehicles. While humps slow response time to 6-7 minutes, the cushions allow emergency vehicles to obtain a more typical response of 4-5 minutes.

The Traffic Logix cushions were chosen based on their prefabricated shape, which can be difficult to create and maintain with asphalt. The products’ modular design ensures that the devices are easy to install and remain firmly in place. The simple installation process ensures that products can be easily moved and relocated. This is particularly advantageous on Bison since the city plans to eventually turn the street into a cul-de-sac and will then reinstall the devices on other local streets.

While a formal traffic study will not be conducted until the Spring, Assistant Traffic Engineer John Wasson reports that residents are happy with the products and the resulting 15-18% reduction in vehicle speed. The Boise Fire Department has been pleased with the speed cushions and may be interested in having them installed along additional fire routes in the future.

The two local commissioners, President John Franden and Commissioner Rebecca Arnold, who were inundated with complaints regarding Bison Street, are quite satisfied as well. As Mr. Wasson reported, in place of complaints, the commissioners are now receiving thank yous.