When the boy in Dutch legend saw a small hole in a dike holding back a potential flood, he didn’t look for ways to make the breach bigger.

The Metropolitan Water Reclamation District should ponder that as it considers a proposal to weaken an ordinance designed to protect water quality and hold the line on flooding.

OPINION

When the MWRD’s Cook County Watershed Management Ordinance was unveiled in 2013 after years of negotiations, it was hailed an important step forward. Too often in heavy storms, basements flood and raw sewage overflows into waterways and Lake Michigan. The ordinance was designed to keep that from getting worse as the growing region is covered over by new buildings and more pavement.

Unfortunately, the MWRD is considering weakening the ordinance in ways that would benefit developers rather than the environment. The agency should insist on more flood-proofing, not less.

The devastation from Hurricane Harvey is a reminder that storms are getting stronger and metropolitan areas will have to deal with more water. Recently, communities along the Fox and Des Plaines rivers suffered heavy flooding. And neighborhoods throughout the Chicago area are vulnerable if they are hit by rainfall so heavy it overwhelms the drainage system.

One unwise proposed change to the MWRD’s water management practices is to allow developers to begin construction before even obtaining approval for flood-control designs. Once soil has been moved around and concrete is in place, it will be difficult and costly to make changes. Opportunities to better handle storm water will be lost.

A second unwise proposed change would allow developers to increase water runoff in one area if they provide equivalent water storage somewhere else. That wouldn’t increase flooding over the region, but the neighbors of these new developments easily could wind up with more water in their basements.

As things work now, if builders in a particular area run into problems with the current MWRD rules, they are permitted to request a variance, which allows solutions to be found on a case-by-case basis. That’s worked just fine, even if it has required a little more paperwork. There’s no justification for weakening the entire ordinance.

On Thursday, the MWRD board was prepared to vote on the proposed changes, but the item was pulled from the agenda to give everyone more time to think about what’s at stake.

Our dry basements are at stake. And the quality of the water in our rivers and lakes.

If the tragedy of Houston has taught us anything, it is that flood control policies in big cities like Chicago must be stringent.

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