Along the North Branch of the Chicago River between Irving Park Road and Lawrence Avenue, the flatland slips away to a hidden place.

Old couples steal away under the canopy to rest on a bench and watch the mallards dabble. Sometimes great blue herons poke around the shore.

This is our Chicago river, strangely evolved descendant of the original meandering wetland stream. Engineers’ transits have simplified its form, channelized its bed, and changed its character. Richard Carter, the Evanston naturalist, describes the channel’s morphology like this: There is the river surface itself. Then there is the flat plain above. In between is a place called the Wild Zone.

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The Wild Zone is one of the last frontiers in North America. Skirmishes have never ceased, Frederick Turner notwithstanding. The Metropolitan Water Reclamation District owns the riverbank. But where are they? Where do they live? And who owns them? Anyway, my neighbor Bill says he owns his riverbank. He’s not kidding. Says it’s on his deed. The city’s legal department says “their position is” that no area resident has the right to claim the land or restrict its public use by building fences or docks. The MWRD calls these things encroachments, and the people who build them encroachers.

But while we were all playing this summer the state legislature passed Senate Bill 1285, a law that enables the MWRD to sell off riverbank property along the North Branch from Belmont to Lawrence. In 1991 a riverside property owner south of Montrose set off a policy review that led to the legislation by unceremoniously constructing an eight-foot-tall chain-link fence and dock extravaganza. Complaints to the alderman were redirected to the MWRD.

One riverfront neighbor, Martin Cohen, a member of both Friedman’s group and Friends of the Chicago River, says the authorization bill was a surprise. River Residents hadn’t been clamoring for the sell-off option. “I have no need to own the riverbank. We think we’re the best friends the river ever had. We do think this document gives us certain rights. No one has challenged for 90 years the use of the riverbanks or the docks.”

Another option suggested was the forced removal of all encroachments. But recognizing that this move might be a public relations disaster, they put it to one side.