Traffic on Anna Salai was hit during rush hour on Thursday after a chemical used to soften the sand for tunnelling operations undertaken by Metro Rail leaked out of an opening and spread on to the road.
Metro Rail officials told Express that the leakage took place around 5 pm on the Anna Salai-Wallajah Road intersection.
“Traffic was affected for nearly 30 minutes and officials cordoned off the area as a result of the spill,” said an official.
“It took nearly three hours to restore the vehicular flow as iron planks were put on the loose soil,” said a Metro Rail spokesman.
The work was carried out using makeshift lights as well as an earthmoving equipment used to transport the iron planks.
Many commuters did not know what caused the delay. Meanwhile, the tunnel work between Government Estate and the LIC building was completed, the spokesman said.