Highest number of accidents on PIE

The Straits Times reported that the Pan Island Expressway (PIE) is the highway where the most traffic accidents occurred over the past three months. Singapore's longest expressway, at 42.8km, had at least 441 accidents, with the highest concentration of 48 accidents, evenly split in both directions, around the Eng Neo Avenue exit. 

The numbers were obtained from more than 2,000 tweets by the Land Transport Authority (LTA)'s @LTAsg Twitter account between 26^th May and 22^nd August. 

Although the PIE had the highest number of accidents, it fell behind the Central Expressway (CTE) and Seletar Expressway (SLE) when the number of accidents was set against the length of the road.

The 15.5km CTE had at least 164 accidents, or 10.58 per km, and the 12km SLE had 125 accidents, or 10.42 per km, compared with the PIE's 10.3 per km.

Aside from Eng Neo, other hot spots that recorded at least 25 accidents include a stretch of the PIE near Paya Lebar, the CTE near the PIE (Changi) exit and the SLE near Mandai Road.

National University of Singapore transport researcher Associate Professor Lee Der Horng said that many crash areas were on the PIE because the oldest expressway was not built to handle the high volume of traffic that now flows through daily.

Prof. Lee said that there is also some undulation on parts of the PIE, where the road rises and falls, and affects how far ahead a motorist can see. "That, coupled with heavy and fast-moving traffic, is what makes parts of the PIE near Mount Pleasant and Stevens Road dangerous," he added.

Like the Eng Neo Avenue to Adam Road portion of the PIE, large curves - such as the one at the CTE near the PIE (Changi) exit - could also cause a 'shockwave', where high-speed traffic meets slower traffic with disastrous consequences.

Dr Park Byung Joon, Head of the Urban Transport Management programme at SIM University, agreed with this assessment, but added that accidents can also happen in tunnels, such as the CTE tunnel near Merchant Road, as drivers expect traffic to be fast-moving.