The failure of consecutive governments to build the North West Rail Link or to invest in significant up-grades on the Western and Richmond lines has isolated Blacktown station as a central hub.

Police figures show that up to 4500 people pass through the station every hour.

Many of these people come from areas outside Blacktown such as Windsor, Richmond or Kellyville, because these suburbs lack frequent public transport.

With the population in Blacktown set to explode by another 60 per cent over the next 20 years, the capacity of Blacktown station will be stretched to the limit and beyond if essential transport infrastructure isn't delivered soon.

Western Sydney Regional Organisation of Councils president Alison McLaren said the failure of governments to build any new railway in western Sydney since the 1930s had left communities stranded.

"The North West Rail Link is a much-needed piece of infrastructure," Ms McLaren said. "For people in Blacktown it's particularly important, because it opens up that region to people looking for work."

The government's plans for the North West Growth Centre include 145,000 jobs by 2036.

The proposed new rail line from Rouse Hill to Epping and the duplication of the line between Quakers Hill and Vineyard would also take pressure off Blacktown.

Government research suggests it will remove 5000 people a day from the peak hours on the Western line.

Tentative steps towards building the rail link have been taken, and a community information centre about the project opened two weeks ago.

But Transport Minister Gladys Berejiklian would not say if train services on the Western line would be cut to serve the north-west.

Ms Berejiklian said the plan was to run between four and six services in peak hour.

Advice to the Labor government in February suggests this will still not be enough.

The director-general of Transport NSW Les Wielinga told the former government that "a minimum of eight trains an hour would be required" to meet the growing demand.