Righting the lighting on roads

Every evening as the sun sets, thousands of street lights flicker to life in the city. But many motorists find that their intensity is not uniform. Though roads including CTH Road, New Avadi Road and Pallavaram-Thoraipakkam Radial Road have enough lamps, their luminosity (brightness of light, especially in the evening hours) is not enough for motorists to drive comfortably after dusk.

“On some roads, there are stretches that are darker than the rest. Even if one lamp does not glow, that area becomes dark and we have to adjust to that sudden darkness. Headlights alone are not enough to drive on city roads,” points out K.R. Senthil Kumar of Bhavani Nagar in Pallavaram.

A year-long study on the level of luminosity at 11 points on seven major roads in the city by the Highways Research Station (HRS) echoes what many road users feel every day. It shows that the average illuminance for most roads is well below required levels. The study was conducted on important roads including Sardar Patel Road, Chennai Tiruvallur High Road, New Avadi Road, Radial Road, Rajiv Gandhi Salai, Gandhi Mandapam Road and Grand Southern Trunk Road.

“There are places where the glow is higher than required, leading to glare. But for safe driving, there must be uniform lighting. Data for 2013 from the Tamil Nadu Road Accident Data Management System shows that a considerable number of accidents happen in the dark, with or without streetlights, and also during twilight, when light is uneven. Better lighting can save lives,” explains an official at HRS.

After the study, the HRS has suggested several steps that could contribute to safe driving at nights. For lighting to be uniform, those in charge of the lights — local bodies or the Highways — need to look at pruning of trees at regular intervals and should check lux (unit of illumination) on a regular basis. The domes of lights should be cleaned regularly to remove accumulated road dust and it should be ensured that the required electrical load is available and all lamps glow.

A luminosity expert suggests that street lights too should have automatic phase changers so that if the supply in one phase goes off, it will utilise power from another phase.

A senior official of Tamil Nadu Generation and Distribution Corporation (Tangedco) says that only if the Highways department and local bodies seek an exclusive distribution network facility for street lights against linking several street lights in the low tension load will the problem of low voltage or non-functioning of street lights not arise. 

T. Sadagopan, consumer activist and resident of Pattabhiram, said that coordination between various departments is necessary to ensure proper lighting. “When roads are widened, the lighting requirement for that stretch must be re-examined. Presently, the Highways department does not install lights as it does not have an electrical wing or enough money to maintain such lights. Such a wing will help roads inside city limits to have better lighting,” he suggests.