Maryland will get about a million new residents in the next 25 years, according to state projections. It’s already one of the most densely populated states in the country. That’s why Gov. Martin O’Malley has instituted an ambitious and controversial plan he says will help manage the state’s growth while protecting rural areas and the Chesapeake Bay. But is he overreaching?

The effort, dubbed PlanMaryland, has drawn praise from the American Planning Association. But rural county leaders and state lawmakers say O’Malley is pushing a state takeover of local land-use decisions that unjustly favors large and liberal jurisdictions. State officials argue that’s not the case, but O’Malley’s fiery response likely isn’t calming his critics. “This is not a wall that prohibits counties from making stupid land-use decisions,” The Washington Post quoted O’Malley saying at a hearing last year. “They’re still free to do that, but we’re not going to subsidize it anymore.”

Basically, PlanMaryland encourages growth in areas that already have built-up infrastructure, in order to avoid the cost of extending that infrastructure to rural areas. It gives localities a strong incentive to share that goal: Those that don’t follow the guidelines will be less likely to receive state discretionary funds.

State officials say it’s the best way to utilize their limited resources. According to Maryland State Planning Secretary Richard Hall, road construction expenses and maintenance costs alone would fall about 30 percent over the next 20 years. The plan will also help preserve more than 300,000 acres of farmland and forest over the next 25 years, according to state estimates.

In 1974, the state’s General Assembly authorized the creation of such a plan to promote “prosperity of the people” through “coordinated development.” But enacting it had been elusive until O’Malley pushed the plan through via executive order in December. Few states have pursued this level of planning, and it’s no surprise that it’s causing some frustration among local leaders.

This year, the nuts and bolts of the plan -- including maps of areas that will be targeted for development -- will be put together. That will be done in concert with localities, Hall says. But Leslie Knapp, associate director of the Maryland Association of Counties, says, “There has been a general feeling of a lack of real participation” among his members.

Knapp doesn’t dispute the state’s authority to develop criteria for distributing discretionary funds. But one of his group’s priorities is to ensure that localities still have the right to pursue projects that don’t conform to the plan, as long as they’re willing to fund them independently of the state.

Hall, meanwhile, is betting that local leaders will come to embrace PlanMaryland. “I think many of those that are wary of it will see that, over time, it makes sense for Maryland,” he says.