Urban sprawl, car-choked streets, old-growth forests under threat.

Greater Montreal hopes to deal with all of these issues via an ambitious, 20-year land use and development plan set to come into effect this spring.

The plan is backed by most local politicians, environmentalists and business groups, although some call it financially unrealistic and others fear it will have the perverse effect of threatening green spaces.

The sprawling Greater Montreal region, encompassing the City of Montreal and 81 surrounding towns and cities, is now home to 3.7 million people — almost half of Quebec’s population. By 2031, the region’s population is expected to grow by 530,000.

The new plan, adopted by municipalities in December and expected to be rubber-stamped by the Quebec government, aims to improve the quality of life of residents and make the region more attractive to business.

The plan is three-pronged:

> Housing: 40% of the projected 320,000 new households to be constructed over the next 20 years are to be located within one kilometre of a train station, subway stop or bus line providing fast, efficient service.

> Transportation: at least $23 billion is to be invested in public transit — extending subway lines, boosting commuter train service, launching bus/rapid-transit lines. The goal is to boost the percentage of people using public transit to 30% by 2021 from the current 25%. Roads also must be improved to reduce chronic traffic delays.

> Environment: 17% of land in the region is to be protected from development. Shores, flood plains and heritage sites are to be protected. Existing green spaces are to be developed to boost ecotourism.

Michel Leblanc, president and CEO of the Board of Trade of Metropolitan Montreal, praises the focus on denser developments that are better linked to transit. But the plan is expensive. Although it does not come with an overall price tag, the cost of all the proposed new public transit alone has raised eyebrows.

Where will cash-strapped governments find the cash? Montreal Mayor Gérald Tremblay has stated that property taxes will not cover the cost and that the revenue must come from diverse sources. He favours a regional toll system, charging drivers every time they cross a bridge to Montreal Island. But his off-island counterparts are vehemently opposed.

The region also is paralyzed by indecision over which of the myriad, repeatedly studied, pricey public transit projects should be funded first. Light-rail transit on the planned new Champlain Bridge? Extend the subway, and in which direction — off-island into the suburbs of Laval and Longueuil or eastward on Montreal Island? Reintroduce streetcars to Montreal? Upgrade spotty train service to western Montreal?

And some people worry the plan’s call for increased density and public transit-oriented developments goes against the goal of preserving green spaces. Activists fear efforts to develop areas around train stations in western Montreal, for example, will lead to building on wetlands, forests and former farm fields that have yet to be officially protected.  IE