During the 1980s, Iowa was one of the earliest states to approve of casino gambling. And it pioneered a new idea for how to control the games: It required that its casinos be water-borne. In Iowa's case, they had to be actual riverboats offering no fewer than 100 excursion tours per year.

It seemed to make sense at the time. Riverboat gambling evoked a nostalgic allure along the Mississippi and offered hope for economic growth to riverfront communities.

But it soon became clear in Iowa that gambling and waterfronts weren't a natural combination. Gamblers were interested in sitting at the slots, not admiring paddlewheels. Very few actually went for tours on the boats, and since betting amounts were severely limited while the tours were going on, the rule simply inconvenienced those ready to give the house some of their money.

Three years ago, Iowa eliminated the requirement that casinos actually move, but they still have to be located on the water. This has served no practical purpose. The casinos were soon either dry- docked or newly built on top of artificially-sustained little puddles. "Basically, it's a tremendous cost to some of the new casinos coming online," says state Senator Mike Connolly, sponsor of a measure to repeal the requirement. "I think most Iowans see this as darned foolishness."

Allowing casinos to build on dry land will not only save their operators money but also help protect the environment. There may not have been much damage to the Mississippi, but casinos in other states sit on top of fragile wetlands. The cars and people they attract have increased pollution in sensitive areas, while the all-night lighting presents problems for birds and wildlife.

There are other reasons for allowing casinos to build on soil, rather than water. It's easier for casinos built on dry land to afford insurance. That's why, following Hurricane Katrina, the Mississippi legislature allowed casinos to be rebuilt as much as 800 feet from the Gulf Coast. Further north, however, Mississippi casinos still must be on rivers or standing water. Four other states continue to allow casinos on water only. Gambling opponents support such strictures as a way of keeping the number of casinos to a minimum.

But Mike Connolly is right. The whole idea is silly. If states want to restrict gambling, they can limit the number of casino licenses they issue. That's a lot better than keeping requirements on the books that are ignored in spirit and cause more problems than they solve.