Commuters face a frustrating wait before they get relief from chronic overcrowding on trams on Sydney's inner west light rail line during peak travel periods.

Passengers say the crowding is a "nightmare" during peak periods despite the introduction of an extra 90 weekly services last year on the 12.8-kilometre line from Central Station to Dulwich Hill.

And the most recent government statistics show the number of passengers using the light rail line surged by 59 per cent to 9.73 million in the 12 months to June last year.

Transport for NSW, the government agency charged with oversight of the networks, said it would continue to monitor passenger numbers on the inner west line but declined to say whether it planned to boost tram services during peak periods.