Inclement Weather and Traffic Flow at Signalized Intersections: Case Study from Northern New England

Abstract

Gridlock along arterial systems in New England is often the result of adverse weather conditions, which can render the normal signal plans unsuitable. The current study has two main objectives: ( a) to assess the impact of inclement weather on traffic flow parameters at signalized intersections in northern New England and ( b) to evaluate the likely operational benefits of implementing special timing plans for inclement weather conditions. A signalized intersection in Burlington, Vermont, was selected, and at least 30 h of videotaped data were collected over a period of 3 months. The weather and road surface conditions were categorized into six different classes, and values for the saturation headways and start-up lost times were collected and statistically analyzed. A signalized collector was then selected as a case study for evaluating the likely benefits of developing special timing plans for inclement weather. Optimal signal plans were developed for the corridor for the six different weather conditions. The likely benefits of the special plans were then determined by comparing travel conditions under the optimal inclement weather timing plans with conditions assuming the optimal dry-condition plan would remain unchanged. The study reveals that inclement weather has a significant impact on saturation headways, particularly once slushy conditions start. Start-up lost time, however, does not appear to be significantly affected by inclement weather. The study also shows that there are benefits to be expected from implementing special signal plans for inclement weather.

Augmenting Traffic Signal Control Systems for Urban Road Networks With Connected Vehicles

“…TRANSYT calculates the optimal signal timings for a given road network model by minimising a performance function consisting of delay, number of stops, and economic factors. TRANSYT has been shown to reduce delay up to 24% over pre-existing signal timing plans in the New England region of the USA [8].…”

Estimation of the effect of motorcycles on the capacity of signalized intersections

“…Lu and Pernıá (2000) analyzed the effect of the proportion of elderly people on l1 and on saturation headways. Agbolosu-Amison (2004) analyzed the effect of climate on l1 and on saturation headways. Khosla and Williams (2006) evaluated the effect of green time on queue discharge.…”

Sensitivity of street network capacity under the rain impact: case study of Belgrade

“…The decrease in free flow speed ranged from 10 to 30%, depending on type of the analysed weather conditions (from rain to slushy paths and wheel road surfaces condition) while the decrease of the saturation flow rate ranged from 6 to 20% (from rainy to snowy and sticking road surfaces condition). A research on the adverse weather impact at a signalised intersection in Burlington (Vermont) was aimed at examining the adverse weather impact on traffic flow characteristics, taking into consideration the longitudinal inclination on one of the intersection legs (Agbolosu-Amison et al 2004). The results showed that under the precipitations there was a lower impact on the saturation flow rate reduction at the intersection leg with inclination (4%), in comparison with intersection leg without inclination (7%).…”