If there’s anything Cook County can be proud of, it is its 68,000 acres of forest preserve, the envy of metropolitan areas around the country.

When anything comes along that harms or encroaches on the preserves, alarm bells should go off.

Those bells should be clanging loudly right now as a plan re-emerges to expand a two-lane road, Quentin Road, into a five-lane highway smack dab through northwest suburban Deer Grove, the oldest forest preserve in the nation.

What is happening to Deer Grove could happen to any county forest preserve where construction and traffic continue to grow. So who decides? We can’t let planners and builders nibble away at green space unchallenged.

EDITORIAL

The idea of a five-lane road between Lake Cook Road and Dundee Road last came up in 2011, but planners agreed to go back to the drawing board. Now, the Cook County Board is preparing to vote late this month or in March on whether to expand the existing two-lane highway, a pleasant ribbon of pavement that invites motorists to stop and enjoy the woods.

One option under consideration is to create a five-lane behemoth. A more reasonable “three-lane” option would add turning lanes to speed up traffic, without creating an unnecessarily huge concrete barrier between the eastern and western halves of the forest preserve. Since the original proposal was made public, both options have added a multiuse path on the west side of the road, underpasses for small animals and realigned entrances.

One thing hasn’t changed since 2011: There is no need for a five-lane road. We agree with environmentalists who say that traffic, while busy during rush hour, moves well enough through the preserve on the existing two-lane road.

Even the best effort to design a five-lane road means glorious mature oaks will be ripped out and more road salt will run off into a multimillion-dollar federal wetland project, killing plants that can’t tolerate salt.

As we’ve argued at such times before, bigger is not necessarily better. No one is talking about taking lakefront parkland to add lanes to Lake Shore Drive. That’s why there is at least some sentiment on the Cook County Board for rejecting both widening options and leaving the road the way it is.

As it happens, the same County Board commissioners who oversee highway projects sit on the forest preserve board, guarding our natural areas. When this comes up for a vote, they should put their environmental responsibilities first.

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