Mistakes add up for flood protection

By far, the wisest person who ever studied Sun Valley flooding was University of Iowa hydrology professor A. Jacob Odgaard. His report's recommendations stated and his drawing showed a proposed flood wall along the west property line of this addition. That essential recommendation was ignored by Cedar Rapids city officials and consultants in their plan and was forgotten by the neighborhood.

Errors like that are inexcusable. No flood protection construction should start until it is certain that all parts can be completed because all are essential.

The neighborhood's greatest problem is not addressed by the proposed flooding protection. That greatest problem is the grossly undersized Cottage Grove bridge opening.

Its small size causes a greater flood within a flood. It causes an ever-larger impoundment backup lake fed by 11 million gallons per minute of inflow. The restricted outflow causes rising water levels until it overflows the Cottage Grove road grade and takes an undesignated route downstream. Recent construction that raised the road grade and the improvements on adjacent property will cause future higher floodwater levels.

'As built” drawings show that 'opening” the flow area under the bridge would increase the flow opening area more than 22 percent. Those responsible for bridge sizing still roam city halls and have said that opening the flow area would provide an insignificant (1 percent) benefit. They've made many other mistakes; determine if this is another.

The waste is very concerning but is really scary if anything similar is happening throughout the city.

This city should copy what smaller cities and towns do and eliminate the multiple layers of engineering services.

' Marv Rops of Cedar Rapids is a retired consulting civil engineer. Comments: (319) 362-4695