Flood reduction a pricey issue on Wapsipinicon

QUASQUETON — Two million dollars does not buy much flood reduction.

That’s one of the conclusions reported during the June 3 public presentation of flood-reduction projects on the Wapsipinicon River and its tributaries.

“We get big reductions immediately downstream of the projects, but it’s a drop in the bucket at the watershed scale,” said Dan Gilles, a water resources engineer with the Iowa Flood Center, one of several partners in the Upper Wapsipinicon River Watershed Management Authority.

The projects — which include ponds, wetlands, oxbow restorations, grass waterways, on-road detention basins, a grade stabilization and a water and sediment control basin — slow the discharge of water from about 4,200 acres.

The affected area, however, constitutes less than half a percent of the 1,003,356-acre Upper Wapsipinicon Watershed, which stretches from the river’s source in southern Minnesota to Anamosa.

Further illustrating the magnitude of the problem, the Flood Center’s Adam Weis, at an April 12 meeting of the Watershed Management Authority, said the projects added about 413 acre-feet of flood storage, which compares with the 609,000 acre-feet that passed through Anamosa during the 2008 flood.

The Flood Center estimates projects costing more than $500 million would be required to effect a 20 percent reduction in the peak of a major Wapsipinicon River flood.

The June 3 tour included five of the 28 projects developed under the auspices of the Upper Wapsipinicon River Watershed Management Authority (of which I am the city of Quasqueton’s representative).

They are part of the Iowa Watershed Approach, which, funded by a $96.9 million federal grant, encompasses the Upper Wapsipinicon and eight other watersheds — Bee Branch Creek near Dubuque, Clear Creek in Iowa and Johnson counties and the following rivers: North Raccoon, West Nishnabotna, East Nishnabotna, English, Middle Cedar and Upper Iowa.

Of the 28 Upper Wapsipinicon projects, 13 are along Smith Creek, which empties into the Wapsipinicon 1.5 miles south of Quasqueton, and 12 are along Dry Creek, which flows into the Wapsipinicon three miles above Troy Mills.

At the local level the projects have reduced flooding, improved water quality and provided wildlife habitat, said Dan Jensen, a water resources engineer with Shive-Hattery, which designed the projects.

All of the projects — funded with a 10 percent landowner match — are in Buchanan County with the exception of three in Delaware County along Nugents Creek, which flows into Buffalo Creek, the Wapsipinicon's largest tributary, near Coggon.

Tori Nimrod and Ross Evelsizer, co-coordinators of the Wapsipinicon initiative and leaders of the June 3 tour, said the projects are a long-overdue first step toward increasing the watershed's capacity to hold water, thus reducing flood peaks on the river.

“It’s been a long time coming. I hope it will stimulate folks to keep the ball rolling,” said John Kurtz, chairman of the Upper Wapsipinicon River Watershed Management Authority.